Merge remote-tracking branch 'origin/master' into tarball-cache

.github/CODEOWNERS

@@ -10,16 +10,8 @@
 # This file
 .github/CODEOWNERS @edolstra
 
-# Public documentation
-/doc @fricklerhandwerk
-*.md @fricklerhandwerk
-
 # Documentation of built-in functions
-src/libexpr/primops.cc @fricklerhandwerk @roberth
+src/libexpr/primops.cc @roberth
-# Documentation on experimental features
-src/libutil/experimental-features.cc @fricklerhandwerk
-# Documentation on configuration settings
-src/libstore/globals.hh @fricklerhandwerk
 
 # Libstore layer
 /src/libstore @thufschmitt

.github/PULL_REQUEST_TEMPLATE.md

@@ -10,6 +10,8 @@
 
 <!-- Large change: Provide instructions to reviewers how to read the diff. -->
 
-# Priorities
+# Priorities and Process
 
 Add :+1: to [pull requests you find important](https://github.com/NixOS/nix/pulls?q=is%3Aopen+sort%3Areactions-%2B1-desc).
+
+The Nix maintainer team uses a [GitHub project board](https://github.com/orgs/NixOS/projects/19) to [schedule and track reviews](https://github.com/NixOS/nix/tree/master/maintainers#project-board-protocol). 

.github/workflows/backport.yml

@@ -21,7 +21,7 @@ jobs:
           fetch-depth: 0
       - name: Create backport PRs
         # should be kept in sync with `version`
-        uses: zeebe-io/backport-action@v2.2.0
+        uses: zeebe-io/backport-action@v2.3.0
         with:
           # Config README: https://github.com/zeebe-io/backport-action#backport-action
           github_token: ${{ secrets.GITHUB_TOKEN }}

Makefile

@@ -24,7 +24,7 @@ makefiles = \
   misc/upstart/local.mk
 endif
 
-ifeq ($(ENABLE_BUILD)_$(ENABLE_TESTS), yes_yes)
+ifeq ($(ENABLE_UNIT_TESTS), yes)
 makefiles += \
   tests/unit/libutil/local.mk \
   tests/unit/libutil-support/local.mk \
@@ -34,16 +34,13 @@ makefiles += \
   tests/unit/libexpr-support/local.mk
 endif
 
-ifeq ($(ENABLE_TESTS), yes)
+ifeq ($(ENABLE_FUNCTIONAL_TESTS), yes)
 makefiles += \
   tests/functional/local.mk \
   tests/functional/ca/local.mk \
   tests/functional/dyn-drv/local.mk \
   tests/functional/test-libstoreconsumer/local.mk \
   tests/functional/plugins/local.mk
-else
-makefiles += \
-  mk/disable-tests.mk
 endif
 
 OPTIMIZE = 1
@@ -57,11 +54,40 @@ endif
 
 include mk/lib.mk
 
+# Must be included after `mk/lib.mk` so isn't the default target.
+ifneq ($(ENABLE_UNIT_TESTS), yes)
+.PHONY: check
+check:
+	@echo "Unit tests are disabled. Configure without '--disable-unit-tests', or avoid calling 'make check'."
+	@exit 1
+endif
+
+ifneq ($(ENABLE_FUNCTIONAL_TESTS), yes)
+.PHONY: installcheck
+installcheck:
+	@echo "Functional tests are disabled. Configure without '--disable-functional-tests', or avoid calling 'make installcheck'."
+	@exit 1
+endif
+
 # Must be included after `mk/lib.mk` so rules refer to variables defined
 # by the library. Rules are not "lazy" like variables, unfortunately.
-ifeq ($(ENABLE_BUILD), yes)
+
+ifeq ($(ENABLE_DOC_GEN), yes)
 $(eval $(call include-sub-makefile, doc/manual/local.mk))
+else
+.PHONY: manual-html manpages
+manual-html manpages:
+	@echo "Generated docs are disabled. Configure without '--disable-doc-gen', or avoid calling 'make manpages' and 'make manual-html'."
+	@exit 1
 endif
+
+ifeq ($(ENABLE_INTERNAL_API_DOCS), yes)
 $(eval $(call include-sub-makefile, doc/internal-api/local.mk))
+else
+.PHONY: internal-api-html
+internal-api-html:
+	@echo "Internal API docs are disabled. Configure with '--enable-internal-api-docs', or avoid calling 'make internal-api-html'."
+	@exit 1
+endif
 
 GLOBAL_CXXFLAGS += -g -Wall -include $(buildprefix)config.h -std=c++2a -I src

Makefile.config.in

@@ -9,8 +9,11 @@ CXXFLAGS = @CXXFLAGS@
 CXXLTO = @CXXLTO@
 EDITLINE_LIBS = @EDITLINE_LIBS@
 ENABLE_BUILD = @ENABLE_BUILD@
+ENABLE_DOC_GEN = @ENABLE_DOC_GEN@
+ENABLE_FUNCTIONAL_TESTS = @ENABLE_FUNCTIONAL_TESTS@
+ENABLE_INTERNAL_API_DOCS = @ENABLE_INTERNAL_API_DOCS@
 ENABLE_S3 = @ENABLE_S3@
-ENABLE_TESTS = @ENABLE_TESTS@
+ENABLE_UNIT_TESTS = @ENABLE_UNIT_TESTS@
 GTEST_LIBS = @GTEST_LIBS@
 HAVE_LIBCPUID = @HAVE_LIBCPUID@
 HAVE_SECCOMP = @HAVE_SECCOMP@
@@ -36,12 +39,10 @@ checkbindir = @checkbindir@
 checklibdir = @checklibdir@
 datadir = @datadir@
 datarootdir = @datarootdir@
-doc_generate = @doc_generate@
 docdir = @docdir@
 embedded_sandbox_shell = @embedded_sandbox_shell@
 exec_prefix = @exec_prefix@
 includedir = @includedir@
-internal_api_docs = @internal_api_docs@
 libdir = @libdir@
 libexecdir = @libexecdir@
 localstatedir = @localstatedir@

configure.ac

@@ -138,20 +138,38 @@ AC_ARG_ENABLE(build, AS_HELP_STRING([--disable-build],[Do not build nix]),
   ENABLE_BUILD=$enableval, ENABLE_BUILD=yes)
 AC_SUBST(ENABLE_BUILD)
 
-# Building without tests is useful for bootstrapping with a smaller footprint
+# Building without unit tests is useful for bootstrapping with a smaller footprint
 # or running the tests in a separate derivation. Otherwise, we do compile and
 # run them.
-AC_ARG_ENABLE(tests, AS_HELP_STRING([--disable-tests],[Do not build the tests]),
-  ENABLE_TESTS=$enableval, ENABLE_TESTS=yes)
-AC_SUBST(ENABLE_TESTS)
 
-# Building without API docs is the default as Nix' C++ interfaces are internal and unstable.
+AC_ARG_ENABLE(unit-tests, AS_HELP_STRING([--disable-unit-tests],[Do not build the tests]),
-AC_ARG_ENABLE(internal_api_docs, AS_HELP_STRING([--enable-internal-api-docs],[Build API docs for Nix's internal unstable C++ interfaces]),
+  ENABLE_UNIT_TESTS=$enableval, ENABLE_UNIT_TESTS=$ENABLE_BUILD)
-  internal_api_docs=$enableval, internal_api_docs=no)
+AC_SUBST(ENABLE_UNIT_TESTS)
-AC_SUBST(internal_api_docs)
 
 AS_IF(
-  [test "$ENABLE_BUILD" == "yes" || test "$ENABLE_TEST" == "yes"],
+  [test "$ENABLE_BUILD" == "no" && test "$ENABLE_UNIT_TESTS" == "yes"],
+  [AC_MSG_ERROR([Cannot enable unit tests when building overall is disabled. Please do not pass '--enable-unit-tests' or do not pass '--disable-build'.])])
+
+AC_ARG_ENABLE(functional-tests, AS_HELP_STRING([--disable-functional-tests],[Do not build the tests]),
+  ENABLE_FUNCTIONAL_TESTS=$enableval, ENABLE_FUNCTIONAL_TESTS=yes)
+AC_SUBST(ENABLE_FUNCTIONAL_TESTS)
+
+# documentation generation switch
+AC_ARG_ENABLE(doc-gen, AS_HELP_STRING([--disable-doc-gen],[disable documentation generation]),
+  ENABLE_DOC_GEN=$enableval, ENABLE_DOC_GEN=$ENABLE_BUILD)
+AC_SUBST(ENABLE_DOC_GEN)
+
+AS_IF(
+  [test "$ENABLE_BUILD" == "no" && test "$ENABLE_GENERATED_DOCS" == "yes"],
+  [AC_MSG_ERROR([Cannot enable generated docs when building overall is disabled. Please do not pass '--enable-doc-gen' or do not pass '--disable-build'.])])
+
+# Building without API docs is the default as Nix' C++ interfaces are internal and unstable.
+AC_ARG_ENABLE(internal-api-docs, AS_HELP_STRING([--enable-internal-api-docs],[Build API docs for Nix's internal unstable C++ interfaces]),
+  ENABLE_INTERNAL_API_DOCS=$enableval, ENABLE_INTERNAL_API_DOCS=no)
+AC_SUBST(ENABLE_INTERNAL_API_DOCS)
+
+AS_IF(
+  [test "$ENABLE_FUNCTIONAL_TESTS" == "yes" || test "$ENABLE_DOC_GEN" == "yes"],
   [NEED_PROG(jq, jq)])
 
 AS_IF([test "$ENABLE_BUILD" == "yes"],[
@@ -317,7 +335,7 @@ if test "$gc" = yes; then
   AC_DEFINE(HAVE_BOEHMGC, 1, [Whether to use the Boehm garbage collector.])
 fi
 
-AS_IF([test "$ENABLE_TESTS" == "yes"],[
+AS_IF([test "$ENABLE_UNIT_TESTS" == "yes"],[
 
 # Look for gtest.
 PKG_CHECK_MODULES([GTEST], [gtest_main])
@@ -349,11 +367,6 @@ AC_LANG_POP(C++)
 # Look for nlohmann/json.
 PKG_CHECK_MODULES([NLOHMANN_JSON], [nlohmann_json >= 3.9])
 
-# documentation generation switch
-AC_ARG_ENABLE(doc-gen, AS_HELP_STRING([--disable-doc-gen],[disable documentation generation]),
-  doc_generate=$enableval, doc_generate=yes)
-AC_SUBST(doc_generate)
-
 
 # Look for lowdown library.
 PKG_CHECK_MODULES([LOWDOWN], [lowdown >= 0.9.0], [CXXFLAGS="$LOWDOWN_CFLAGS $CXXFLAGS"])

doc/internal-api/local.mk

@@ -1,19 +1,7 @@
-.PHONY: internal-api-html
-
-ifeq ($(internal_api_docs), yes)
-
 $(docdir)/internal-api/html/index.html $(docdir)/internal-api/latex: $(d)/doxygen.cfg
 	mkdir -p $(docdir)/internal-api
 	{ cat $< ; echo "OUTPUT_DIRECTORY=$(docdir)/internal-api" ; } | doxygen -
 
 # Generate the HTML API docs for Nix's unstable internal interfaces.
+.PHONY: internal-api-html
 internal-api-html: $(docdir)/internal-api/html/index.html
-
-else
-
-# Make a nicer error message
-internal-api-html:
-	@echo "Internal API docs are disabled. Configure with '--enable-internal-api-docs', or avoid calling 'make internal-api-html'."
-	@exit 1
-
-endif

doc/manual/local.mk

@@ -1,5 +1,3 @@
-ifeq ($(doc_generate),yes)
-
 # The version of Nix used to generate the doc. Can also be
 # `$(nix_INSTALL_PATH)` or just `nix` (to grap ambient from the `PATH`),
 # if one prefers.
@@ -180,6 +178,8 @@ manual-html: $(docdir)/manual/index.html
 install: $(docdir)/manual/index.html
 
 # Generate 'nix' manpages.
+.PHONY: manpages
+manpages: $(mandir)/man1/nix3-manpages
 install: $(mandir)/man1/nix3-manpages
 man: doc/manual/generated/man1/nix3-manpages
 all: doc/manual/generated/man1/nix3-manpages
@@ -225,5 +225,3 @@ $(docdir)/manual/index.html: $(MANUAL_SRCS) $(d)/book.toml $(d)/anchors.jq $(d)/
 	@rm -rf $(DESTDIR)$(docdir)/manual
 	@mv $(DESTDIR)$(docdir)/manual.tmp/html $(DESTDIR)$(docdir)/manual
 	@rm -rf $(DESTDIR)$(docdir)/manual.tmp
-
-endif

doc/manual/rl-next/nix-profile-names.md

@@ -0,0 +1,6 @@
+---
+synopsis: "`nix profile` now allows referring to elements by human-readable name"
+prs: 8678
+---
+
+[`nix profile`](@docroot@/command-ref/new-cli/nix3-profile.md) now uses names to refer to installed packages when running [`list`](@docroot@/command-ref/new-cli/nix3-profile-list.md), [`remove`](@docroot@/command-ref/new-cli/nix3-profile-remove.md) or [`upgrade`](@docroot@/command-ref/new-cli/nix3-profile-upgrade.md) as opposed to indices. Indices are deprecated and will be removed in a future version.

doc/manual/src/contributing/hacking.md

@@ -64,6 +64,27 @@ $ nix build
 
 You can also build Nix for one of the [supported platforms](#platforms).
 
+## Makefile variables
+
+You may need `profiledir=$out/etc/profile.d` and `sysconfdir=$out/etc` to run
+`make install`.
+
+You may want to set `MAKEFLAGS="-e -j $NIX_BUILD_CORES"` to allow environment
+variables to override `Makefile` variables.
+
+- `ENABLE_BUILD=yes` to enable building the C++ code.
+- `ENABLE_DOC_GEN=yes` to enable building the documentation (manual, man pages, etc.).
+
+  The docs can take a while to build, so you may want to disable this for local development.
+- `ENABLE_FUNCTIONAL_TESTS=yes` to enable building the functional tests.
+- `ENABLE_UNIT_TESTS=yes` to enable building the unit tests.
+- `OPTIMIZE=1` to enable optimizations.
+- `libraries=libutil programs=` to only build a specific library (this will
+  fail in the linking phase if you don't have the other libraries built, but is
+  useful for checking types).
+- `libraries= programs=nix` to only build a specific program (this will not, in
+  general, work, because the programs need the libraries).
+
 ## Building Nix
 
 To build all dependencies and start a shell in which all environment variables are set up so that those dependencies can be found:

doc/manual/src/installation/prerequisites-source.md

@@ -72,7 +72,7 @@
     This is an optional dependency and can be disabled
     by providing a `--disable-cpuid` to the `configure` script.
 
-  - Unless `./configure --disable-tests` is specified, GoogleTest (GTest) and
+  - Unless `./configure --disable-unit-tests` is specified, GoogleTest (GTest) and
     RapidCheck are required, which are available at
     <https://google.github.io/googletest/> and
     <https://github.com/emil-e/rapidcheck> respectively.

flake.nix

@@ -395,7 +395,7 @@
           stdenvs)));
 
       devShells = let
-        makeShell = pkgs: stdenv: (pkgs.nix.override { inherit stdenv; }).overrideAttrs (attrs: {
+        makeShell = pkgs: stdenv: (pkgs.nix.override { inherit stdenv; forDevShell = true; }).overrideAttrs (attrs: {
           installFlags = "sysconfdir=$(out)/etc";
           shellHook = ''
             PATH=$prefix/bin:$PATH

mk/disable-tests.mk

@@ -1,12 +0,0 @@
-# This file is only active for `./configure --disable-tests`.
-# Running `make check` or `make installcheck` would indicate a mistake in the
-# caller.
-
-installcheck:
-	@echo "Tests are disabled. Configure without '--disable-tests', or avoid calling 'make installcheck'."
-	@exit 1
-
-# This currently has little effect.
-check:
-	@echo "Tests are disabled. Configure without '--disable-tests', or avoid calling 'make check'."
-	@exit 1

package.nix

@@ -87,6 +87,9 @@
 , test-daemon ? null
 , test-client ? null
 
+# Avoid setting things that would interfere with a functioning devShell
+, forDevShell ? false
+
 # Not a real argument, just the only way to approximate let-binding some
 # stuff for argument defaults.
 , __forDefaults ? {
@@ -104,30 +107,6 @@ let
     inherit doBuild doCheck doInstallCheck;
   };
 
-  filesets = {
-    baseFiles = fileset.fileFilter (f: f.name != ".gitignore") ./.;
-
-    configureFiles = fileset.unions [
-      ./.version
-      ./configure.ac
-      ./m4
-      # TODO: do we really need README.md? It doesn't seem used in the build.
-      ./README.md
-    ];
-
-    topLevelBuildFiles = fileset.unions [
-      ./local.mk
-      ./Makefile
-      ./Makefile.config.in
-      ./mk
-    ];
-
-    functionalTestFiles = fileset.unions [
-      ./tests/functional
-      (fileset.fileFilter (f: lib.strings.hasPrefix "nix-profile" f.name) ./scripts)
-    ];
-  };
-
   mkDerivation =
     if withCoverageChecks
     then
@@ -151,32 +130,44 @@ mkDerivation (finalAttrs: let
   # to be run later, requiresthe unit tests to be built.
   buildUnitTests = doCheck || installUnitTests;
 
-  anySortOfTesting = buildUnitTests || doInstallCheck;
-
 in {
   inherit pname version;
 
   src =
     let
-
+      baseFiles = fileset.fileFilter (f: f.name != ".gitignore") ./.;
     in
       fileset.toSource {
         root = ./.;
-        fileset = fileset.intersect filesets.baseFiles (fileset.unions ([
+        fileset = fileset.intersect baseFiles (fileset.unions ([
-          filesets.configureFiles
+          # For configure
-          filesets.topLevelBuildFiles
+          ./.version
-          ./doc/internal-api
+          ./configure.ac
+          ./m4
+          # TODO: do we really need README.md? It doesn't seem used in the build.
+          ./README.md
+          # For make, regardless of what we are building
+          ./local.mk
+          ./Makefile
+          ./Makefile.config.in
+          ./mk
+          (fileset.fileFilter (f: lib.strings.hasPrefix "nix-profile" f.name) ./scripts)
         ] ++ lib.optionals doBuild [
           ./boehmgc-coroutine-sp-fallback.diff
           ./doc
           ./misc
           ./precompiled-headers.h
           ./src
-          ./tests/unit
           ./COPYING
           ./scripts/local.mk
-        ] ++ lib.optionals anySortOfTesting [
+        ] ++ lib.optionals buildUnitTests [
-          filesets.functionalTestFiles
+          ./doc/manual
+        ] ++ lib.optionals enableInternalAPIDocs [
+          ./doc/internal-api
+        ] ++ lib.optionals buildUnitTests [
+          ./tests/unit
+        ] ++ lib.optionals doInstallCheck [
+          ./tests/functional
         ]));
       };
 
@@ -275,12 +266,14 @@ in {
   );
 
   configureFlags = [
-    "--sysconfdir=/etc"
     (lib.enableFeature doBuild "build")
-    (lib.enableFeature anySortOfTesting "tests")
+    (lib.enableFeature buildUnitTests "unit-tests")
+    (lib.enableFeature doInstallCheck "functional-tests")
     (lib.enableFeature enableInternalAPIDocs "internal-api-docs")
     (lib.enableFeature enableManual "doc-gen")
     (lib.enableFeature installUnitTests "install-unit-tests")
+  ] ++ lib.optionals (!forDevShell) [
+    "--sysconfdir=/etc"
   ] ++ lib.optionals installUnitTests [
     "--with-check-bin-dir=${builtins.placeholder "check"}/bin"
     "--with-check-lib-dir=${builtins.placeholder "check"}/lib"
@@ -310,10 +303,7 @@ in {
   '';
 
   postInstall = lib.optionalString doBuild (
-    ''
+    lib.optionalString stdenv.hostPlatform.isStatic ''
-      mkdir -p $doc/nix-support
-      echo "doc manual $doc/share/doc/nix/manual" >> $doc/nix-support/hydra-build-products
-    '' + lib.optionalString stdenv.hostPlatform.isStatic ''
       mkdir -p $out/nix-support
       echo "file binary-dist $out/bin/nix" >> $out/nix-support/hydra-build-products
     '' + lib.optionalString stdenv.isDarwin ''
@@ -322,7 +312,10 @@ in {
       $out/lib/libboost_context.dylib \
       $out/lib/libnixutil.dylib
     ''
-  ) + lib.optionalString enableInternalAPIDocs ''
+  ) + lib.optionalString enableManual ''
+    mkdir -p ''${!outputDoc}/nix-support
+    echo "doc manual ''${!outputDoc}/share/doc/nix/manual" >> ''${!outputDoc}/nix-support/hydra-build-products
+  '' + lib.optionalString enableInternalAPIDocs ''
     mkdir -p ''${!outputDoc}/nix-support
     echo "doc internal-api-docs $out/share/doc/nix/internal-api/html" >> ''${!outputDoc}/nix-support/hydra-build-products
   '';

perl/lib/Nix/Store.xs

@@ -13,6 +13,7 @@
 #include "globals.hh"
 #include "store-api.hh"
 #include "crypto.hh"
+#include "posix-source-accessor.hh"
 
 #include <sodium.h>
 #include <nlohmann/json.hpp>
@@ -205,7 +206,10 @@ void importPaths(int fd, int dontCheckSigs)
 SV * hashPath(char * algo, int base32, char * path)
     PPCODE:
         try {
-            Hash h = hashPath(parseHashAlgo(algo), path).first;
+            PosixSourceAccessor accessor;
+            Hash h = hashPath(
+                accessor, CanonPath::fromCwd(path),
+                FileIngestionMethod::Recursive, parseHashAlgo(algo)).first;
             auto s = h.to_string(base32 ? HashFormat::Nix32 : HashFormat::Base16, false);
             XPUSHs(sv_2mortal(newSVpv(s.c_str(), 0)));
         } catch (Error & e) {
@@ -281,7 +285,11 @@ SV * addToStore(char * srcPath, int recursive, char * algo)
     PPCODE:
         try {
             auto method = recursive ? FileIngestionMethod::Recursive : FileIngestionMethod::Flat;
-            auto path = store()->addToStore(std::string(baseNameOf(srcPath)), srcPath, method, parseHashAlgo(algo));
+            PosixSourceAccessor accessor;
+            auto path = store()->addToStore(
+                std::string(baseNameOf(srcPath)),
+                accessor, CanonPath::fromCwd(srcPath),
+                method, parseHashAlgo(algo));
             XPUSHs(sv_2mortal(newSVpv(store()->printStorePath(path).c_str(), 0)));
         } catch (Error & e) {
             croak("%s", e.what());

scripts/install-darwin-multi-user.sh

@@ -3,11 +3,13 @@
 set -eu
 set -o pipefail
 
+# System specific settings
+export NIX_FIRST_BUILD_UID="${NIX_FIRST_BUILD_UID:-301}"
+export NIX_BUILD_USER_NAME_TEMPLATE="_nixbld%d"
+
 readonly NIX_DAEMON_DEST=/Library/LaunchDaemons/org.nixos.nix-daemon.plist
 # create by default; set 0 to DIY, use a symlink, etc.
 readonly NIX_VOLUME_CREATE=${NIX_VOLUME_CREATE:-1} # now default
-NIX_FIRST_BUILD_UID="301"
-NIX_BUILD_USER_NAME_TEMPLATE="_nixbld%d"
 
 # caution: may update times on / if not run as normal non-root user
 read_only_root() {

scripts/install-multi-user.sh

@@ -25,9 +25,9 @@ readonly RED='\033[31m'
 readonly NIX_USER_COUNT=${NIX_USER_COUNT:-32}
 readonly NIX_BUILD_GROUP_ID="${NIX_BUILD_GROUP_ID:-30000}"
 readonly NIX_BUILD_GROUP_NAME="nixbld"
-# darwin installer needs to override these
+# each system specific installer must set these:
-NIX_FIRST_BUILD_UID="${NIX_FIRST_BUILD_UID:-30001}"
+#   NIX_FIRST_BUILD_UID
-NIX_BUILD_USER_NAME_TEMPLATE="nixbld%d"
+#   NIX_BUILD_USER_NAME_TEMPLATE
 # Please don't change this. We don't support it, because the
 # default shell profile that comes with Nix doesn't support it.
 readonly NIX_ROOT="/nix"
@@ -707,6 +707,12 @@ EOF
     fi
 }
 
+check_required_system_specific_settings() {
+    if [ -z "${NIX_FIRST_BUILD_UID+x}" ] || [ -z "${NIX_BUILD_USER_NAME_TEMPLATE+x}" ]; then
+        failure "Internal error: System specific installer for $(uname) ($1) does not export required settings."
+    fi
+}
+
 welcome_to_nix() {
     local -r NIX_UID_RANGES="${NIX_FIRST_BUILD_UID}..$((NIX_FIRST_BUILD_UID + NIX_USER_COUNT - 1))"
     local -r RANGE_TEXT=$(echo -ne "${BLUE}(uids [${NIX_UID_RANGES}])${ESC}")
@@ -726,7 +732,9 @@ manager. This will happen in a few stages:
    if you are ready to continue.
 
 3. Create the system users ${RANGE_TEXT} and groups ${GROUP_TEXT}
-   that the Nix daemon uses to run builds.
+   that the Nix daemon uses to run builds. To create system users
+   in a different range, exit and run this tool again with
+   NIX_FIRST_BUILD_UID set.
 
 4. Perform the basic installation of the Nix files daemon.
 
@@ -968,13 +976,16 @@ main() {
     if is_os_darwin; then
         # shellcheck source=./install-darwin-multi-user.sh
         . "$EXTRACTED_NIX_PATH/install-darwin-multi-user.sh"
+        check_required_system_specific_settings "install-darwin-multi-user.sh"
     elif is_os_linux; then
         # shellcheck source=./install-systemd-multi-user.sh
         . "$EXTRACTED_NIX_PATH/install-systemd-multi-user.sh" # most of this works on non-systemd distros also
+        check_required_system_specific_settings "install-systemd-multi-user.sh"
     else
         failure "Sorry, I don't know what to do on $(uname)"
     fi
 
+
     welcome_to_nix
 
     if ! is_root; then

scripts/install-systemd-multi-user.sh

@@ -3,6 +3,10 @@
 set -eu
 set -o pipefail
 
+# System specific settings
+export NIX_FIRST_BUILD_UID="${NIX_FIRST_BUILD_UID:-30001}"
+export NIX_BUILD_USER_NAME_TEMPLATE="nixbld%d"
+
 readonly SERVICE_SRC=/lib/systemd/system/nix-daemon.service
 readonly SERVICE_DEST=/etc/systemd/system/nix-daemon.service
 

src/libcmd/installable-value.cc

@@ -44,7 +44,7 @@ ref<InstallableValue> InstallableValue::require(ref<Installable> installable)
 std::optional<DerivedPathWithInfo> InstallableValue::trySinglePathToDerivedPaths(Value & v, const PosIdx pos, std::string_view errorCtx)
 {
     if (v.type() == nPath) {
-        auto storePath = v.path().fetchToStore(state->store);
+        auto storePath = v.path().fetchToStore(*state->store);
         return {{
             .path = DerivedPath::Opaque {
                 .path = std::move(storePath),

src/libexpr/eval.cc

@@ -2317,7 +2317,7 @@ StorePath EvalState::copyPathToStore(NixStringContext & context, const SourcePat
     auto dstPath = i != srcToStore.end()
         ? i->second
         : [&]() {
-            auto dstPath = path.fetchToStore(store, path.baseName(), FileIngestionMethod::Recursive, nullptr, repair);
+            auto dstPath = path.fetchToStore(*store, path.baseName(), FileIngestionMethod::Recursive, nullptr, repair);
             allowPath(dstPath);
             srcToStore.insert_or_assign(path, dstPath);
             printMsg(lvlChatty, "copied source '%1%' -> '%2%'", path, store->printStorePath(dstPath));

src/libexpr/flake/flakeref.cc

@@ -190,7 +190,7 @@ std::optional<std::pair<FlakeRef, std::string>> parseFlakeIdRef(
 
     static std::regex flakeRegex(
         "((" + flakeIdRegexS + ")(?:/(?:" + refAndOrRevRegex + "))?)"
-        + "(?:#(" + queryRegex + "))?",
+        + "(?:#(" + fragmentRegex + "))?",
         std::regex::ECMAScript);
 
     if (std::regex_match(url, match, flakeRegex)) {

src/libexpr/flake/url-name.cc

@@ -0,0 +1,48 @@
+#include "url-name.hh"
+#include <regex>
+#include <iostream>
+
+namespace nix {
+
+static const std::string attributeNamePattern("[a-z0-9_-]+");
+static const std::regex lastAttributeRegex("(?:" + attributeNamePattern + "\\.)*(?!default)(" + attributeNamePattern +")(\\^.*)?");
+static const std::string pathSegmentPattern("[a-zA-Z0-9_-]+");
+static const std::regex lastPathSegmentRegex(".*/(" + pathSegmentPattern +")");
+static const std::regex secondPathSegmentRegex("(?:" + pathSegmentPattern + ")/(" + pathSegmentPattern +")(?:/.*)?");
+static const std::regex gitProviderRegex("github|gitlab|sourcehut");
+static const std::regex gitSchemeRegex("git($|\\+.*)");
+static const std::regex defaultOutputRegex(".*\\.default($|\\^.*)");
+
+std::optional<std::string> getNameFromURL(const ParsedURL & url)
+{
+    std::smatch match;
+
+    /* If there is a dir= argument, use its value */
+    if (url.query.count("dir") > 0)
+        return url.query.at("dir");
+
+    /* If the fragment isn't a "default" and contains two attribute elements, use the last one */
+    if (std::regex_match(url.fragment, match, lastAttributeRegex))
+        return match.str(1);
+
+    /* If this is a github/gitlab/sourcehut flake, use the repo name */
+    if (std::regex_match(url.scheme, gitProviderRegex) && std::regex_match(url.path, match, secondPathSegmentRegex))
+        return match.str(1);
+
+    /* If it is a regular git flake, use the directory name */
+    if (std::regex_match(url.scheme, gitSchemeRegex) && std::regex_match(url.path, match, lastPathSegmentRegex))
+        return match.str(1);
+
+    /* If everything failed but there is a non-default fragment, use it in full */
+    if (!url.fragment.empty() && !std::regex_match(url.fragment, defaultOutputRegex))
+        return url.fragment;
+
+    /* If there is no fragment, take the last element of the path */
+    if (std::regex_match(url.path, match, lastPathSegmentRegex))
+        return match.str(1);
+
+    /* If even that didn't work, the URL does not contain enough info to determine a useful name */
+    return {};
+}
+
+}

src/libexpr/flake/url-name.hh

@@ -0,0 +1,20 @@
+#include "url.hh"
+#include "url-parts.hh"
+#include "util.hh"
+#include "split.hh"
+
+namespace nix {
+
+/**
+ * Try to extract a reasonably unique and meaningful, human-readable
+ * name of a flake output from a parsed URL.
+ * When nullopt is returned, the callsite should use information available
+ * to it outside of the URL to determine a useful name.
+ * This is a heuristic approach intended for user interfaces.
+ * @return nullopt if the extracted name is not useful to identify a
+ * flake output, for example because it is empty or "default".
+ * Otherwise returns the extracted name.
+ */
+std::optional<std::string> getNameFromURL(const ParsedURL & url);
+
+}

src/libexpr/primops.cc

@@ -438,9 +438,7 @@ static RegisterPrimOp primop_isNull({
     .doc = R"(
       Return `true` if *e* evaluates to `null`, and `false` otherwise.
 
-      > **Warning**
+      This is equivalent to `e == null`.
-      >
-      > This function is *deprecated*; just write `e == null` instead.
     )",
     .fun = prim_isNull,
 });
@@ -2072,8 +2070,14 @@ static void prim_toFile(EvalState & state, const PosIdx pos, Value * * args, Val
     }
 
     auto storePath = settings.readOnlyMode
-        ? state.store->computeStorePathForText(name, contents, refs)
+        ? state.store->makeFixedOutputPathFromCA(name, TextInfo {
-        : state.store->addTextToStore(name, contents, refs, state.repair);
+            .hash = hashString(HashAlgorithm::SHA256, contents),
+            .references = std::move(refs),
+        })
+        : ({
+            StringSource s { contents };
+            state.store->addToStoreFromDump(s, name, TextIngestionMethod {}, HashAlgorithm::SHA256, refs, state.repair);
+        });
 
     /* Note: we don't need to add `context' to the context of the
        result, since `storePath' itself has references to the paths
@@ -2229,7 +2233,7 @@ static void addPath(
             });
 
         if (!expectedHash || !state.store->isValidPath(*expectedStorePath)) {
-            auto dstPath = path.fetchToStore(state.store, name, method, filter.get(), state.repair);
+            auto dstPath = path.fetchToStore(*state.store, name, method, filter.get(), state.repair);
             if (expectedHash && expectedStorePath != dstPath)
                 state.debugThrowLastTrace(Error("store path mismatch in (possibly filtered) path added from '%s'", path));
             state.allowAndSetStorePathString(dstPath, v);

src/libfetchers/cache.cc

@@ -106,7 +106,7 @@ struct CacheImpl : Cache
     }
 
     void add(
-        ref<Store> store,
+        Store & store,
         const Attrs & inAttrs,
         const Attrs & infoAttrs,
         const StorePath & storePath,
@@ -115,13 +115,13 @@ struct CacheImpl : Cache
         _state.lock()->add.use()
             (attrsToJSON(inAttrs).dump())
             (attrsToJSON(infoAttrs).dump())
-            (store->printStorePath(storePath))
+            (store.printStorePath(storePath))
             (locked)
             (time(0)).exec();
     }
 
     std::optional<std::pair<Attrs, StorePath>> lookup(
-        ref<Store> store,
+        Store & store,
         const Attrs & inAttrs) override
     {
         if (auto res = lookupExpired(store, inAttrs)) {
@@ -134,7 +134,7 @@ struct CacheImpl : Cache
     }
 
     std::optional<Result> lookupExpired(
-        ref<Store> store,
+        Store & store,
         const Attrs & inAttrs) override
     {
         auto state(_state.lock());
@@ -148,19 +148,19 @@ struct CacheImpl : Cache
         }
 
         auto infoJSON = stmt.getStr(0);
-        auto storePath = store->parseStorePath(stmt.getStr(1));
+        auto storePath = store.parseStorePath(stmt.getStr(1));
         auto locked = stmt.getInt(2) != 0;
         auto timestamp = stmt.getInt(3);
 
-        store->addTempRoot(storePath);
+        store.addTempRoot(storePath);
-        if (!store->isValidPath(storePath)) {
+        if (!store.isValidPath(storePath)) {
             // FIXME: we could try to substitute 'storePath'.
             debug("ignoring disappeared cache entry '%s'", inAttrsJSON);
             return {};
         }
 
         debug("using cache entry '%s' -> '%s', '%s'",
-            inAttrsJSON, infoJSON, store->printStorePath(storePath));
+            inAttrsJSON, infoJSON, store.printStorePath(storePath));
 
         return Result {
             .expired = !locked && (settings.tarballTtl.get() == 0 || timestamp + settings.tarballTtl < time(0)),

src/libfetchers/cache.hh

@@ -50,14 +50,14 @@ struct Cache
 
     /* Old cache for things that have a store path. */
     virtual void add(
-        ref<Store> store,
+        Store & store,
         const Attrs & inAttrs,
         const Attrs & infoAttrs,
         const StorePath & storePath,
         bool locked) = 0;
 
     virtual std::optional<std::pair<Attrs, StorePath>> lookup(
-        ref<Store> store,
+        Store & store,
         const Attrs & inAttrs) = 0;
 
     struct Result
@@ -68,7 +68,7 @@ struct Cache
     };
 
     virtual std::optional<Result> lookupExpired(
-        ref<Store> store,
+        Store & store,
         const Attrs & inAttrs) = 0;
 };
 

src/libfetchers/fetchers.cc

@@ -374,7 +374,7 @@ void InputScheme::clone(const Input & input, const Path & destDir) const
 std::pair<StorePath, Input> InputScheme::fetch(ref<Store> store, const Input & input)
 {
     auto [accessor, input2] = getAccessor(store, input);
-    auto storePath = SourcePath(accessor).fetchToStore(store, input2.getName());
+    auto storePath = SourcePath(accessor).fetchToStore(*store, input2.getName());
     return {storePath, input2};
 }
 

src/libfetchers/git.cc

@@ -368,14 +368,14 @@ struct GitInputScheme : InputScheme
 
     RepoInfo getRepoInfo(const Input & input) const
     {
-        auto checkHashType = [&](const std::optional<Hash> & hash)
+        auto checkHashAlgorithm = [&](const std::optional<Hash> & hash)
         {
             if (hash.has_value() && !(hash->algo == HashAlgorithm::SHA1 || hash->algo == HashAlgorithm::SHA256))
                 throw Error("Hash '%s' is not supported by Git. Supported types are sha1 and sha256.", hash->to_string(HashFormat::Base16, true));
         };
 
         if (auto rev = input.getRev())
-            checkHashType(rev);
+            checkHashAlgorithm(rev);
 
         RepoInfo repoInfo;
 

src/libfetchers/input-accessor.cc

@@ -5,10 +5,10 @@
 namespace nix {
 
 StorePath InputAccessor::fetchToStore(
-    ref<Store> store,
+    Store & store,
     const CanonPath & path,
     std::string_view name,
-    FileIngestionMethod method,
+    ContentAddressMethod method,
     PathFilter * filter,
     RepairFlag repair)
 {
@@ -20,10 +20,24 @@ StorePath InputAccessor::fetchToStore(
     if (!filter && fingerprint) {
         cacheKey = fetchers::Attrs{
             {"_what", "fetchToStore"},
-            {"store", store->storeDir},
+            {"store", store.storeDir},
             {"name", std::string(name)},
             {"fingerprint", *fingerprint},
-            {"method", (uint8_t) method},
+            {
+                "method",
+                std::visit(overloaded {
+                    [](const TextIngestionMethod &) {
+                        return "text";
+                    },
+                    [](const FileIngestionMethod & fim) {
+                        switch (fim) {
+                        case FileIngestionMethod::Flat: return "flat";
+                        case FileIngestionMethod::Recursive: return "nar";
+                        default: assert(false);
+                        }
+                    },
+                }, method.raw),
+            },
             {"path", path.abs()}
         };
         if (auto res = fetchers::getCache()->lookup(store, *cacheKey)) {
@@ -35,17 +49,14 @@ StorePath InputAccessor::fetchToStore(
 
     Activity act(*logger, lvlChatty, actUnknown, fmt("copying '%s' to the store", showPath(path)));
 
-    auto source = sinkToSource([&](Sink & sink) {
+    auto filter2 = filter ? *filter : defaultPathFilter;
-        if (method == FileIngestionMethod::Recursive)
-            dumpPath(path, sink, filter ? *filter : defaultPathFilter);
-        else
-            readFile(path, sink);
-    });
 
     auto storePath =
         settings.readOnlyMode
-        ? store->computeStorePathFromDump(*source, name, method, HashAlgorithm::SHA256).first
+        ? store.computeStorePath(
-        : store->addToStoreFromDump(*source, name, method, HashAlgorithm::SHA256, repair);
+            name, *this, path, method, HashAlgorithm::SHA256, {}, filter2).first
+        : store.addToStore(
+            name, *this, path, method, HashAlgorithm::SHA256, {}, filter2, repair);
 
     if (cacheKey)
         fetchers::getCache()->add(store, *cacheKey, {}, storePath, true);
@@ -60,9 +71,9 @@ std::ostream & operator << (std::ostream & str, const SourcePath & path)
 }
 
 StorePath SourcePath::fetchToStore(
-    ref<Store> store,
+    Store & store,
     std::string_view name,
-    FileIngestionMethod method,
+    ContentAddressMethod method,
     PathFilter * filter,
     RepairFlag repair) const
 {

src/libfetchers/input-accessor.hh

@@ -30,10 +30,10 @@ struct InputAccessor : virtual SourceAccessor, std::enable_shared_from_this<Inpu
     }
 
     StorePath fetchToStore(
-        ref<Store> store,
+        Store & store,
         const CanonPath & path,
         std::string_view name = "source",
-        FileIngestionMethod method = FileIngestionMethod::Recursive,
+        ContentAddressMethod method = FileIngestionMethod::Recursive,
         PathFilter * filter = nullptr,
         RepairFlag repair = NoRepair);
 };
@@ -116,9 +116,9 @@ struct SourcePath
      * Copy this `SourcePath` to the Nix store.
      */
     StorePath fetchToStore(
-        ref<Store> store,
+        Store & store,
         std::string_view name = "source",
-        FileIngestionMethod method = FileIngestionMethod::Recursive,
+        ContentAddressMethod method = FileIngestionMethod::Recursive,
         PathFilter * filter = nullptr,
         RepairFlag repair = NoRepair) const;
 

src/libfetchers/mercurial.cc

@@ -6,6 +6,7 @@
 #include "tarfile.hh"
 #include "store-api.hh"
 #include "url-parts.hh"
+#include "posix-source-accessor.hh"
 
 #include "fetch-settings.hh"
 
@@ -210,7 +211,12 @@ struct MercurialInputScheme : InputScheme
                     return files.count(file);
                 };
 
-                auto storePath = store->addToStore(input.getName(), actualPath, FileIngestionMethod::Recursive, HashAlgorithm::SHA256, filter);
+                PosixSourceAccessor accessor;
+                auto storePath = store->addToStore(
+                    input.getName(),
+                    accessor, CanonPath { actualPath },
+                    FileIngestionMethod::Recursive, HashAlgorithm::SHA256, {},
+                    filter);
 
                 return {std::move(storePath), input};
             }
@@ -218,7 +224,7 @@ struct MercurialInputScheme : InputScheme
 
         if (!input.getRef()) input.attrs.insert_or_assign("ref", "default");
 
-        auto checkHashType = [&](const std::optional<Hash> & hash)
+        auto checkHashAlgorithm = [&](const std::optional<Hash> & hash)
         {
             if (hash.has_value() && hash->algo != HashAlgorithm::SHA1)
                 throw Error("Hash '%s' is not supported by Mercurial. Only sha1 is supported.", hash->to_string(HashFormat::Base16, true));
@@ -227,7 +233,7 @@ struct MercurialInputScheme : InputScheme
 
         auto getLockedAttrs = [&]()
         {
-            checkHashType(input.getRev());
+            checkHashAlgorithm(input.getRev());
 
             return Attrs({
                 {"type", "hg"},
@@ -246,7 +252,7 @@ struct MercurialInputScheme : InputScheme
         };
 
         if (input.getRev()) {
-            if (auto res = getCache()->lookup(store, getLockedAttrs()))
+            if (auto res = getCache()->lookup(*store, getLockedAttrs()))
                 return makeResult(res->first, std::move(res->second));
         }
 
@@ -259,7 +265,7 @@ struct MercurialInputScheme : InputScheme
             {"ref", *input.getRef()},
         });
 
-        if (auto res = getCache()->lookup(store, unlockedAttrs)) {
+        if (auto res = getCache()->lookup(*store, unlockedAttrs)) {
             auto rev2 = Hash::parseAny(getStrAttr(res->first, "rev"), HashAlgorithm::SHA1);
             if (!input.getRev() || input.getRev() == rev2) {
                 input.attrs.insert_or_assign("rev", rev2.gitRev());
@@ -305,7 +311,7 @@ struct MercurialInputScheme : InputScheme
         auto revCount = std::stoull(tokens[1]);
         input.attrs.insert_or_assign("ref", tokens[2]);
 
-        if (auto res = getCache()->lookup(store, getLockedAttrs()))
+        if (auto res = getCache()->lookup(*store, getLockedAttrs()))
             return makeResult(res->first, std::move(res->second));
 
         Path tmpDir = createTempDir();
@@ -315,7 +321,8 @@ struct MercurialInputScheme : InputScheme
 
         deletePath(tmpDir + "/.hg_archival.txt");
 
-        auto storePath = store->addToStore(name, tmpDir);
+        PosixSourceAccessor accessor;
+        auto storePath = store->addToStore(name, accessor, CanonPath { tmpDir });
 
         Attrs infoAttrs({
             {"rev", input.getRev()->gitRev()},
@@ -324,14 +331,14 @@ struct MercurialInputScheme : InputScheme
 
         if (!_input.getRev())
             getCache()->add(
-                store,
+                *store,
                 unlockedAttrs,
                 infoAttrs,
                 storePath,
                 false);
 
         getCache()->add(
-            store,
+            *store,
             getLockedAttrs(),
             infoAttrs,
             storePath,

src/libfetchers/tarball.cc

@@ -8,6 +8,7 @@
 #include "tarfile.hh"
 #include "types.hh"
 #include "split.hh"
+#include "posix-source-accessor.hh"
 
 namespace nix::fetchers {
 
@@ -26,7 +27,7 @@ DownloadFileResult downloadFile(
         {"name", name},
     });
 
-    auto cached = getCache()->lookupExpired(store, inAttrs);
+    auto cached = getCache()->lookupExpired(*store, inAttrs);
 
     auto useCached = [&]() -> DownloadFileResult
     {
@@ -91,7 +92,7 @@ DownloadFileResult downloadFile(
     }
 
     getCache()->add(
-        store,
+        *store,
         inAttrs,
         infoAttrs,
         *storePath,
@@ -99,7 +100,7 @@ DownloadFileResult downloadFile(
 
     if (url != res.effectiveUri)
         getCache()->add(
-            store,
+            *store,
             {
                 {"type", "file"},
                 {"url", res.effectiveUri},
@@ -130,7 +131,7 @@ DownloadTarballResult downloadTarball(
         {"name", name},
     });
 
-    auto cached = getCache()->lookupExpired(store, inAttrs);
+    auto cached = getCache()->lookupExpired(*store, inAttrs);
 
     if (cached && !cached->expired)
         return {
@@ -156,7 +157,8 @@ DownloadTarballResult downloadTarball(
             throw nix::Error("tarball '%s' contains an unexpected number of top-level files", url);
         auto topDir = tmpDir + "/" + members.begin()->name;
         lastModified = lstat(topDir).st_mtime;
-        unpackedStorePath = store->addToStore(name, topDir, FileIngestionMethod::Recursive, HashAlgorithm::SHA256, defaultPathFilter, NoRepair);
+        PosixSourceAccessor accessor;
+        unpackedStorePath = store->addToStore(name, accessor, CanonPath { topDir }, FileIngestionMethod::Recursive, HashAlgorithm::SHA256, {}, defaultPathFilter, NoRepair);
     }
 
     Attrs infoAttrs({
@@ -168,7 +170,7 @@ DownloadTarballResult downloadTarball(
         infoAttrs.emplace("immutableUrl", *res.immutableUrl);
 
     getCache()->add(
-        store,
+        *store,
         inAttrs,
         infoAttrs,
         *unpackedStorePath,

src/libstore/binary-cache-store.cc

@@ -12,6 +12,7 @@
 #include "thread-pool.hh"
 #include "callback.hh"
 #include "signals.hh"
+#include "archive.hh"
 
 #include <chrono>
 #include <future>
@@ -300,24 +301,60 @@ void BinaryCacheStore::addToStore(const ValidPathInfo & info, Source & narSource
     }});
 }
 
-StorePath BinaryCacheStore::addToStoreFromDump(Source & dump, std::string_view name,
+StorePath BinaryCacheStore::addToStoreFromDump(
-                                               FileIngestionMethod method, HashAlgorithm hashAlgo, RepairFlag repair, const StorePathSet & references)
+    Source & dump,
+    std::string_view name,
+    ContentAddressMethod method,
+    HashAlgorithm hashAlgo,
+    const StorePathSet & references,
+    RepairFlag repair)
 {
+    std::optional<Hash> caHash;
+    std::string nar;
+
+    if (auto * dump2p = dynamic_cast<StringSource *>(&dump)) {
+        auto & dump2 = *dump2p;
+        // Hack, this gives us a "replayable" source so we can compute
+        // multiple hashes more easily.
+        caHash = hashString(HashAlgorithm::SHA256, dump2.s);
+        switch (method.getFileIngestionMethod()) {
+        case FileIngestionMethod::Recursive:
+            // The dump is already NAR in this case, just use it.
+            nar = dump2.s;
+            break;
+        case FileIngestionMethod::Flat:
+            // The dump is Flat, so we need to convert it to NAR with a
+            // single file.
+            StringSink s;
+            dumpString(dump2.s, s);
+            nar = std::move(s.s);
+            break;
+        }
+    } else {
+        // Otherwise, we have to do th same hashing as NAR so our single
+        // hash will suffice for both purposes.
         if (method != FileIngestionMethod::Recursive || hashAlgo != HashAlgorithm::SHA256)
             unsupported("addToStoreFromDump");
-    return addToStoreCommon(dump, repair, CheckSigs, [&](HashResult nar) {
+    }
+    StringSource narDump { nar };
+
+    // Use `narDump` if we wrote to `nar`.
+    Source & narDump2 = nar.size() > 0
+        ? static_cast<Source &>(narDump)
+        : dump;
+
+    return addToStoreCommon(narDump2, repair, CheckSigs, [&](HashResult nar) {
         ValidPathInfo info {
             *this,
             name,
-            FixedOutputInfo {
+            ContentAddressWithReferences::fromParts(
-                .method = method,
+                method,
-                .hash = nar.first,
+                caHash ? *caHash : nar.first,
-                .references = {
+                {
                     .others = references,
                     // caller is not capable of creating a self-reference, because this is content-addressed without modulus
                     .self = false,
-                },
+                }),
-            },
             nar.first,
         };
         info.narSize = nar.second;
@@ -400,71 +437,35 @@ void BinaryCacheStore::queryPathInfoUncached(const StorePath & storePath,
 
 StorePath BinaryCacheStore::addToStore(
     std::string_view name,
-        const Path & srcPath,
+    SourceAccessor & accessor,
-        FileIngestionMethod method,
+    const CanonPath & path,
+    ContentAddressMethod method,
     HashAlgorithm hashAlgo,
+    const StorePathSet & references,
     PathFilter & filter,
-        RepairFlag repair,
+    RepairFlag repair)
-        const StorePathSet & references)
 {
     /* FIXME: Make BinaryCacheStore::addToStoreCommon support
        non-recursive+sha256 so we can just use the default
        implementation of this method in terms of addToStoreFromDump. */
 
-    HashSink sink { hashAlgo };
+    auto h = hashPath(accessor, path, method.getFileIngestionMethod(), hashAlgo, filter).first;
-    if (method == FileIngestionMethod::Recursive) {
-        dumpPath(srcPath, sink, filter);
-    } else {
-        readFile(srcPath, sink);
-    }
-    auto h = sink.finish().first;
 
     auto source = sinkToSource([&](Sink & sink) {
-        dumpPath(srcPath, sink, filter);
+        accessor.dumpPath(path, sink, filter);
     });
     return addToStoreCommon(*source, repair, CheckSigs, [&](HashResult nar) {
         ValidPathInfo info {
             *this,
             name,
-            FixedOutputInfo {
+            ContentAddressWithReferences::fromParts(
-                .method = method,
+                method,
-                .hash = h,
+                h,
-                .references = {
+                {
                     .others = references,
                     // caller is not capable of creating a self-reference, because this is content-addressed without modulus
                     .self = false,
-                },
+                }),
-            },
-            nar.first,
-        };
-        info.narSize = nar.second;
-        return info;
-    })->path;
-}
-
-StorePath BinaryCacheStore::addTextToStore(
-    std::string_view name,
-    std::string_view s,
-    const StorePathSet & references,
-    RepairFlag repair)
-{
-    auto textHash = hashString(HashAlgorithm::SHA256, s);
-    auto path = makeTextPath(name, TextInfo { { textHash }, references });
-
-    if (!repair && isValidPath(path))
-        return path;
-
-    StringSink sink;
-    dumpString(s, sink);
-    StringSource source(sink.s);
-    return addToStoreCommon(source, repair, CheckSigs, [&](HashResult nar) {
-        ValidPathInfo info {
-            *this,
-            std::string { name },
-            TextInfo {
-                .hash = textHash,
-                .references = references,
-            },
             nar.first,
         };
         info.narSize = nar.second;

src/libstore/binary-cache-store.hh

@@ -123,22 +123,22 @@ public:
     void addToStore(const ValidPathInfo & info, Source & narSource,
         RepairFlag repair, CheckSigsFlag checkSigs) override;
 
-    StorePath addToStoreFromDump(Source & dump, std::string_view name,
+    StorePath addToStoreFromDump(
-                                 FileIngestionMethod method, HashAlgorithm hashAlgo, RepairFlag repair, const StorePathSet & references) override;
+        Source & dump,
+        std::string_view name,
+        ContentAddressMethod method,
+        HashAlgorithm hashAlgo,
+        const StorePathSet & references,
+        RepairFlag repair) override;
 
     StorePath addToStore(
         std::string_view name,
-            const Path & srcPath,
+        SourceAccessor & accessor,
-            FileIngestionMethod method,
+        const CanonPath & srcPath,
+        ContentAddressMethod method,
         HashAlgorithm hashAlgo,
-            PathFilter & filter,
-            RepairFlag repair,
-            const StorePathSet & references) override;
-
-    StorePath addTextToStore(
-        std::string_view name,
-        std::string_view s,
         const StorePathSet & references,
+        PathFilter & filter,
         RepairFlag repair) override;
 
     void registerDrvOutput(const Realisation & info) override;

src/libstore/build/local-derivation-goal.cc

@@ -20,6 +20,7 @@
 #include "child.hh"
 #include "unix-domain-socket.hh"
 #include "posix-fs-canonicalise.hh"
+#include "posix-source-accessor.hh"
 
 #include <regex>
 #include <queue>
@@ -1291,12 +1292,13 @@ struct RestrictedStore : public virtual RestrictedStoreConfig, public virtual In
 
     StorePath addToStore(
         std::string_view name,
-            const Path & srcPath,
+        SourceAccessor & accessor,
-            FileIngestionMethod method,
+        const CanonPath & srcPath,
+        ContentAddressMethod method,
         HashAlgorithm hashAlgo,
+        const StorePathSet & references,
         PathFilter & filter,
-            RepairFlag repair,
+        RepairFlag repair) override
-            const StorePathSet & references) override
     { throw Error("addToStore"); }
 
     void addToStore(const ValidPathInfo & info, Source & narSource,
@@ -1306,26 +1308,15 @@ struct RestrictedStore : public virtual RestrictedStoreConfig, public virtual In
         goal.addDependency(info.path);
     }
 
-    StorePath addTextToStore(
-        std::string_view name,
-        std::string_view s,
-        const StorePathSet & references,
-        RepairFlag repair = NoRepair) override
-    {
-        auto path = next->addTextToStore(name, s, references, repair);
-        goal.addDependency(path);
-        return path;
-    }
-
     StorePath addToStoreFromDump(
         Source & dump,
         std::string_view name,
-            FileIngestionMethod method,
+        ContentAddressMethod method,
         HashAlgorithm hashAlgo,
-            RepairFlag repair,
+        const StorePathSet & references,
-            const StorePathSet & references) override
+        RepairFlag repair) override
     {
-        auto path = next->addToStoreFromDump(dump, name, method, hashAlgo, repair, references);
+        auto path = next->addToStoreFromDump(dump, name, method, hashAlgo, references, repair);
         goal.addDependency(path);
         return path;
     }
@@ -2453,8 +2444,7 @@ SingleDrvOutputs LocalDerivationGoal::registerOutputs()
                 throw BuildError(
                     "output path %1% without valid stats info",
                     actualPath);
-            if (outputHash.method == ContentAddressMethod { FileIngestionMethod::Flat } ||
+            if (outputHash.method.getFileIngestionMethod() == FileIngestionMethod::Flat)
-                outputHash.method == ContentAddressMethod { TextIngestionMethod {} })
             {
                 /* The output path should be a regular file without execute permission. */
                 if (!S_ISREG(st->st_mode) || (st->st_mode & S_IXUSR) != 0)
@@ -2466,38 +2456,23 @@ SingleDrvOutputs LocalDerivationGoal::registerOutputs()
             rewriteOutput(outputRewrites);
             /* FIXME optimize and deduplicate with addToStore */
             std::string oldHashPart { scratchPath->hashPart() };
-            HashModuloSink caSink {outputHash.hashAlgo, oldHashPart };
+            auto got = ({
-            std::visit(overloaded {
+                HashModuloSink caSink { outputHash.hashAlgo, oldHashPart };
-                [&](const TextIngestionMethod &) {
+                PosixSourceAccessor accessor;
-                    readFile(actualPath, caSink);
+                dumpPath(
-                },
+                    accessor, CanonPath { actualPath },
-                [&](const FileIngestionMethod & m2) {
+                    caSink,
-                    switch (m2) {
+                    outputHash.method.getFileIngestionMethod());
-                    case FileIngestionMethod::Recursive:
+                caSink.finish().first;
-                        dumpPath(actualPath, caSink);
+            });
-                        break;
-                    case FileIngestionMethod::Flat:
-                        readFile(actualPath, caSink);
-                        break;
-                    }
-                },
-            }, outputHash.method.raw);
-            auto got = caSink.finish().first;
 
-            auto optCA = ContentAddressWithReferences::fromPartsOpt(
-                outputHash.method,
-                std::move(got),
-                rewriteRefs());
-            if (!optCA) {
-                // TODO track distinct failure modes separately (at the time of
-                // writing there is just one but `nullopt` is unclear) so this
-                // message can't get out of sync.
-                throw BuildError("output path '%s' has illegal content address, probably a spurious self-reference with text hashing");
-            }
             ValidPathInfo newInfo0 {
                 worker.store,
                 outputPathName(drv->name, outputName),
-                std::move(*optCA),
+                ContentAddressWithReferences::fromParts(
+                    outputHash.method,
+                    std::move(got),
+                    rewriteRefs()),
                 Hash::dummy,
             };
             if (*scratchPath != newInfo0.path) {
@@ -2511,9 +2486,14 @@ SingleDrvOutputs LocalDerivationGoal::registerOutputs()
                                std::string(newInfo0.path.hashPart())}});
             }
 
-            HashResult narHashAndSize = hashPath(HashAlgorithm::SHA256, actualPath);
+            {
+                PosixSourceAccessor accessor;
+                HashResult narHashAndSize = hashPath(
+                    accessor, CanonPath { actualPath },
+                    FileIngestionMethod::Recursive, HashAlgorithm::SHA256);
                 newInfo0.narHash = narHashAndSize.first;
                 newInfo0.narSize = narHashAndSize.second;
+            }
 
             assert(newInfo0.ca);
             return newInfo0;
@@ -2531,7 +2511,10 @@ SingleDrvOutputs LocalDerivationGoal::registerOutputs()
                         std::string { scratchPath->hashPart() },
                         std::string { requiredFinalPath.hashPart() });
                 rewriteOutput(outputRewrites);
-                auto narHashAndSize = hashPath(HashAlgorithm::SHA256, actualPath);
+                PosixSourceAccessor accessor;
+                HashResult narHashAndSize = hashPath(
+                    accessor, CanonPath { actualPath },
+                    FileIngestionMethod::Recursive, HashAlgorithm::SHA256);
                 ValidPathInfo newInfo0 { requiredFinalPath, narHashAndSize.first };
                 newInfo0.narSize = narHashAndSize.second;
                 auto refs = rewriteRefs();

src/libstore/build/sandbox-defaults.sb

@@ -68,6 +68,7 @@ R""(
 (allow file*
        (literal "/dev/null")
        (literal "/dev/random")
+       (literal "/dev/stderr")
        (literal "/dev/stdin")
        (literal "/dev/stdout")
        (literal "/dev/tty")

src/libstore/build/worker.cc

@@ -519,7 +519,9 @@ bool Worker::pathContentsGood(const StorePath & path)
     if (!pathExists(store.printStorePath(path)))
         res = false;
     else {
-        HashResult current = hashPath(info->narHash.algo, store.printStorePath(path));
+        HashResult current = hashPath(
+            *store.getFSAccessor(), CanonPath { store.printStorePath(path) },
+            FileIngestionMethod::Recursive, info->narHash.algo);
         Hash nullHash(HashAlgorithm::SHA256);
         res = info->narHash == nullHash || info->narHash == current.first;
     }

src/libstore/content-address.cc

@@ -50,6 +50,18 @@ std::string ContentAddressMethod::render(HashAlgorithm ha) const
     }, raw);
 }
 
+FileIngestionMethod ContentAddressMethod::getFileIngestionMethod() const
+{
+    return std::visit(overloaded {
+        [&](const TextIngestionMethod & th) {
+            return FileIngestionMethod::Flat;
+        },
+        [&](const FileIngestionMethod & fim) {
+            return fim;
+        }
+    }, raw);
+}
+
 std::string ContentAddress::render() const
 {
     return std::visit(overloaded {
@@ -79,7 +91,7 @@ static std::pair<ContentAddressMethod, HashAlgorithm> parseContentAddressMethodP
         prefix = *optPrefix;
     }
 
-    auto parseHashType_ = [&](){
+    auto parseHashAlgorithm_ = [&](){
         auto hashTypeRaw = splitPrefixTo(rest, ':');
         if (!hashTypeRaw)
             throw UsageError("content address hash must be in form '<algo>:<hash>', but found: %s", wholeInput);
@@ -90,7 +102,7 @@ static std::pair<ContentAddressMethod, HashAlgorithm> parseContentAddressMethodP
     // Switch on prefix
     if (prefix == "text") {
         // No parsing of the ingestion method, "text" only support flat.
-        HashAlgorithm hashAlgo = parseHashType_();
+        HashAlgorithm hashAlgo = parseHashAlgorithm_();
         return {
             TextIngestionMethod {},
             std::move(hashAlgo),
@@ -100,7 +112,7 @@ static std::pair<ContentAddressMethod, HashAlgorithm> parseContentAddressMethodP
         auto method = FileIngestionMethod::Flat;
         if (splitPrefix(rest, "r:"))
             method = FileIngestionMethod::Recursive;
-        HashAlgorithm hashAlgo = parseHashType_();
+        HashAlgorithm hashAlgo = parseHashAlgorithm_();
         return {
             std::move(method),
             std::move(hashAlgo),
@@ -176,13 +188,13 @@ ContentAddressWithReferences ContentAddressWithReferences::withoutRefs(const Con
     }, ca.method.raw);
 }
 
-std::optional<ContentAddressWithReferences> ContentAddressWithReferences::fromPartsOpt(
+ContentAddressWithReferences ContentAddressWithReferences::fromParts(
-    ContentAddressMethod method, Hash hash, StoreReferences refs) noexcept
+    ContentAddressMethod method, Hash hash, StoreReferences refs)
 {
     return std::visit(overloaded {
-        [&](TextIngestionMethod _) -> std::optional<ContentAddressWithReferences> {
+        [&](TextIngestionMethod _) -> ContentAddressWithReferences {
             if (refs.self)
-                return std::nullopt;
+                throw Error("self-reference not allowed with text hashing");
             return ContentAddressWithReferences {
                 TextInfo {
                     .hash = std::move(hash),
@@ -190,7 +202,7 @@ std::optional<ContentAddressWithReferences> ContentAddressWithReferences::fromPa
                 }
             };
         },
-        [&](FileIngestionMethod m2) -> std::optional<ContentAddressWithReferences> {
+        [&](FileIngestionMethod m2) -> ContentAddressWithReferences {
             return ContentAddressWithReferences {
                 FixedOutputInfo {
                     .method = m2,

src/libstore/content-address.hh

@@ -4,6 +4,7 @@
 #include <variant>
 #include "hash.hh"
 #include "path.hh"
+#include "file-content-address.hh"
 #include "comparator.hh"
 #include "variant-wrapper.hh"
 
@@ -31,22 +32,6 @@ namespace nix {
  */
 struct TextIngestionMethod : std::monostate { };
 
-/**
- * An enumeration of the main ways we can serialize file system
- * objects.
- */
-enum struct FileIngestionMethod : uint8_t {
-    /**
-     * Flat-file hashing. Directly ingest the contents of a single file
-     */
-    Flat = 0,
-    /**
-     * Recursive (or NAR) hashing. Serializes the file-system object in Nix
-     * Archive format and ingest that
-     */
-    Recursive = 1
-};
-
 /**
  * Compute the prefix to the hash algorithm which indicates how the
  * files were ingested.
@@ -54,7 +39,7 @@ enum struct FileIngestionMethod : uint8_t {
 std::string makeFileIngestionPrefix(FileIngestionMethod m);
 
 /**
- * An enumeration of all the ways we can serialize file system objects.
+ * An enumeration of all the ways we can content-address store objects.
  *
  * Just the type of a content address. Combine with the hash itself, and
  * we have a `ContentAddress` as defined below. Combine that, in turn,
@@ -102,7 +87,15 @@ struct ContentAddressMethod
      *
      * The rough inverse of `parse()`.
      */
-    std::string render(HashAlgorithm ha) const;
+    std::string render(HashAlgorithm ht) const;
+
+    /**
+     * Get the underlying way to content-address file system objects.
+     *
+     * Different ways of hashing store objects may use the same method
+     * for hashing file systeme objects.
+     */
+    FileIngestionMethod getFileIngestionMethod() const;
 };
 
 
@@ -116,11 +109,11 @@ struct ContentAddressMethod
  * serialisation methods (flat file vs NAR). Thus, ‘ca’ has one of the
  * following forms:
  *
- * - ‘text:sha256:<sha256 hash of file contents>’: For paths
+ * - `TextIngestionMethod`:
- *   computed by Store::makeTextPath() / Store::addTextToStore().
+ *   ‘text:sha256:<sha256 hash of file contents>’
  *
- * - ‘fixed:<r?>:<ht>:<h>’: For paths computed by
+ * - `FixedIngestionMethod`:
- *   Store::makeFixedOutputPath() / Store::addToStore().
+ *   ‘fixed:<r?>:<hash type>:<hash of file contents>’
  */
 struct ContentAddress
 {
@@ -266,11 +259,12 @@ struct ContentAddressWithReferences
      *
      * @param refs References to other store objects or oneself.
      *
-     * Do note that not all combinations are supported; `nullopt` is
+     * @note note that all combinations are supported. This is a
-     * returns for invalid combinations.
+     * *partial function* and exceptions will be thrown for invalid
+     * combinations.
      */
-    static std::optional<ContentAddressWithReferences> fromPartsOpt(
+    static ContentAddressWithReferences fromParts(
-        ContentAddressMethod method, Hash hash, StoreReferences refs) noexcept;
+        ContentAddressMethod method, Hash hash, StoreReferences refs);
 
     ContentAddressMethod getMethod() const;
 

src/libstore/daemon.cc

@@ -403,22 +403,9 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
                 auto [contentAddressMethod, hashAlgo_] = ContentAddressMethod::parse(camStr);
                 auto hashAlgo = hashAlgo_; // work around clang bug
                 FramedSource source(from);
-                // TODO this is essentially RemoteStore::addCAToStore. Move it up to Store.
+                // TODO these two steps are essentially RemoteStore::addCAToStore. Move it up to Store.
-                return std::visit(overloaded {
+                auto path = store->addToStoreFromDump(source, name, contentAddressMethod, hashAlgo, refs, repair);
-                    [&](const TextIngestionMethod &) {
-                        if (hashAlgo != HashAlgorithm::SHA256)
-                            throw UnimplementedError("When adding text-hashed data called '%s', only SHA-256 is supported but '%s' was given",
-                                name, printHashAlgo(hashAlgo));
-                        // We could stream this by changing Store
-                        std::string contents = source.drain();
-                        auto path = store->addTextToStore(name, contents, refs, repair);
                 return store->queryPathInfo(path);
-                    },
-                    [&](const FileIngestionMethod & fim) {
-                        auto path = store->addToStoreFromDump(source, name, fim, hashAlgo, repair, refs);
-                        return store->queryPathInfo(path);
-                    },
-                }, contentAddressMethod.raw);
             }();
             logger->stopWork();
 
@@ -496,7 +483,10 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
         std::string s = readString(from);
         auto refs = WorkerProto::Serialise<StorePathSet>::read(*store, rconn);
         logger->startWork();
-        auto path = store->addTextToStore(suffix, s, refs, NoRepair);
+        auto path = ({
+            StringSource source { s };
+            store->addToStoreFromDump(source, suffix, TextIngestionMethod {}, HashAlgorithm::SHA256, refs, NoRepair);
+        });
         logger->stopWork();
         to << store->printStorePath(path);
         break;

src/libstore/derivations.cc

@@ -143,8 +143,14 @@ StorePath writeDerivation(Store & store,
     auto suffix = std::string(drv.name) + drvExtension;
     auto contents = drv.unparse(store, false);
     return readOnly || settings.readOnlyMode
-        ? store.computeStorePathForText(suffix, contents, references)
+        ? store.makeFixedOutputPathFromCA(suffix, TextInfo {
-        : store.addTextToStore(suffix, contents, references, repair);
+            .hash = hashString(HashAlgorithm::SHA256, contents),
+            .references = std::move(references),
+        })
+        : ({
+            StringSource s { contents };
+            store.addToStoreFromDump(s, suffix, TextIngestionMethod {}, HashAlgorithm::SHA256, references, repair);
+        });
 }
 
 

src/libstore/dummy-store.cc

@@ -58,13 +58,6 @@ struct DummyStore : public virtual DummyStoreConfig, public virtual Store
         RepairFlag repair, CheckSigsFlag checkSigs) override
     { unsupported("addToStore"); }
 
-    StorePath addTextToStore(
-        std::string_view name,
-        std::string_view s,
-        const StorePathSet & references,
-        RepairFlag repair) override
-    { unsupported("addTextToStore"); }
-
     void narFromPath(const StorePath & path, Sink & sink) override
     { unsupported("narFromPath"); }
 

src/libstore/globals.hh

@@ -631,7 +631,7 @@ public:
 
           At least one of the following condition must be met
           for Nix to accept copying a store object from another
-          Nix store (such as a substituter):
+          Nix store (such as a [substituter](#conf-substituters)):
 
           - the store object has been signed using a key in the trusted keys list
           - the [`require-sigs`](#conf-require-sigs) option has been set to `false`

src/libstore/legacy-ssh-store.hh

@@ -60,20 +60,14 @@ struct LegacySSHStore : public virtual LegacySSHStoreConfig, public virtual Stor
 
     StorePath addToStore(
         std::string_view name,
-            const Path & srcPath,
+        SourceAccessor & accessor,
-            FileIngestionMethod method,
+        const CanonPath & srcPath,
+        ContentAddressMethod method,
         HashAlgorithm hashAlgo,
-            PathFilter & filter,
-            RepairFlag repair,
-            const StorePathSet & references) override
-    { unsupported("addToStore"); }
-
-    StorePath addTextToStore(
-        std::string_view name,
-        std::string_view s,
         const StorePathSet & references,
+        PathFilter & filter,
         RepairFlag repair) override
-    { unsupported("addTextToStore"); }
+    { unsupported("addToStore"); }
 
 private:
 

src/libstore/local-store.cc

@@ -13,6 +13,7 @@
 #include "compression.hh"
 #include "signals.hh"
 #include "posix-fs-canonicalise.hh"
+#include "posix-source-accessor.hh"
 
 #include <iostream>
 #include <algorithm>
@@ -1088,11 +1089,22 @@ void LocalStore::addToStore(const ValidPathInfo & info, Source & source,
 
             if (info.ca) {
                 auto & specified = *info.ca;
-                auto actualHash = hashCAPath(
+                auto actualHash = ({
-                    specified.method,
+                    HashModuloSink caSink {
                         specified.hash.algo,
-                    info.path
+                        std::string { info.path.hashPart() },
-                );
+                    };
+                    PosixSourceAccessor accessor;
+                    dumpPath(
+                        *getFSAccessor(false),
+                        CanonPath { printStorePath(info.path) },
+                        caSink,
+                        specified.method.getFileIngestionMethod());
+                    ContentAddress {
+                        .method = specified.method,
+                        .hash = caSink.finish().first,
+                    };
+                });
                 if (specified.hash != actualHash.hash) {
                     throw Error("ca hash mismatch importing path '%s';\n  specified: %s\n  got:       %s",
                         printStorePath(info.path),
@@ -1115,8 +1127,13 @@ void LocalStore::addToStore(const ValidPathInfo & info, Source & source,
 }
 
 
-StorePath LocalStore::addToStoreFromDump(Source & source0, std::string_view name,
+StorePath LocalStore::addToStoreFromDump(
-                                         FileIngestionMethod method, HashAlgorithm hashAlgo, RepairFlag repair, const StorePathSet & references)
+    Source & source0,
+    std::string_view name,
+    ContentAddressMethod method,
+    HashAlgorithm hashAlgo,
+    const StorePathSet & references,
+    RepairFlag repair)
 {
     /* For computing the store path. */
     auto hashSink = std::make_unique<HashSink>(hashAlgo);
@@ -1166,25 +1183,21 @@ StorePath LocalStore::addToStoreFromDump(Source & source0, std::string_view name
         delTempDir = std::make_unique<AutoDelete>(tempDir);
         tempPath = tempDir + "/x";
 
-        if (method == FileIngestionMethod::Recursive)
+        restorePath(tempPath, bothSource, method.getFileIngestionMethod());
-            restorePath(tempPath, bothSource);
-        else
-            writeFile(tempPath, bothSource);
 
         dump.clear();
     }
 
     auto [hash, size] = hashSink->finish();
 
-    ContentAddressWithReferences desc = FixedOutputInfo {
+    auto desc = ContentAddressWithReferences::fromParts(
-        .method = method,
+        method,
-        .hash = hash,
+        hash,
-        .references = {
+        {
             .others = references,
             // caller is not capable of creating a self-reference, because this is content-addressed without modulus
             .self = false,
-        },
+        });
-    };
 
     auto dstPath = makeFixedOutputPathFromCA(name, desc);
 
@@ -1207,11 +1220,8 @@ StorePath LocalStore::addToStoreFromDump(Source & source0, std::string_view name
 
             if (inMemory) {
                 StringSource dumpSource { dump };
-                /* Restore from the NAR in memory. */
+                /* Restore from the buffer in memory. */
-                if (method == FileIngestionMethod::Recursive)
+                restorePath(realPath, dumpSource, method.getFileIngestionMethod());
-                    restorePath(realPath, dumpSource);
-                else
-                    writeFile(realPath, dumpSource);
             } else {
                 /* Move the temporary path we restored above. */
                 moveFile(tempPath, realPath);
@@ -1247,58 +1257,6 @@ StorePath LocalStore::addToStoreFromDump(Source & source0, std::string_view name
 }
 
 
-StorePath LocalStore::addTextToStore(
-    std::string_view name,
-    std::string_view s,
-    const StorePathSet & references, RepairFlag repair)
-{
-    auto hash = hashString(HashAlgorithm::SHA256, s);
-    auto dstPath = makeTextPath(name, TextInfo {
-        .hash = hash,
-        .references = references,
-    });
-
-    addTempRoot(dstPath);
-
-    if (repair || !isValidPath(dstPath)) {
-
-        auto realPath = Store::toRealPath(dstPath);
-
-        PathLocks outputLock({realPath});
-
-        if (repair || !isValidPath(dstPath)) {
-
-            deletePath(realPath);
-
-            autoGC();
-
-            writeFile(realPath, s);
-
-            canonicalisePathMetaData(realPath, {});
-
-            StringSink sink;
-            dumpString(s, sink);
-            auto narHash = hashString(HashAlgorithm::SHA256, sink.s);
-
-            optimisePath(realPath, repair);
-
-            ValidPathInfo info { dstPath, narHash };
-            info.narSize = sink.s.size();
-            info.references = references;
-            info.ca = {
-                .method = TextIngestionMethod {},
-                .hash = hash,
-            };
-            registerValidPath(info);
-        }
-
-        outputLock.setDeletion(true);
-    }
-
-    return dstPath;
-}
-
-
 /* Create a temporary directory in the store that won't be
    garbage-collected until the returned FD is closed. */
 std::pair<Path, AutoCloseFD> LocalStore::createTempDirInStore()
@@ -1389,7 +1347,10 @@ bool LocalStore::verifyStore(bool checkContents, RepairFlag repair)
         for (auto & link : readDirectory(linksDir)) {
             printMsg(lvlTalkative, "checking contents of '%s'", link.name);
             Path linkPath = linksDir + "/" + link.name;
-            std::string hash = hashPath(HashAlgorithm::SHA256, linkPath).first.to_string(HashFormat::Nix32, false);
+            PosixSourceAccessor accessor;
+            std::string hash = hashPath(
+                accessor, CanonPath { linkPath },
+                FileIngestionMethod::Recursive, HashAlgorithm::SHA256).first.to_string(HashFormat::Nix32, false);
             if (hash != link.name) {
                 printError("link '%s' was modified! expected hash '%s', got '%s'",
                     linkPath, link.name, hash);
@@ -1696,42 +1657,6 @@ void LocalStore::queryRealisationUncached(const DrvOutput & id,
     }
 }
 
-ContentAddress LocalStore::hashCAPath(
-    const ContentAddressMethod & method, const HashAlgorithm & hashAlgo,
-    const StorePath & path)
-{
-    return hashCAPath(method, hashAlgo, Store::toRealPath(path), path.hashPart());
-}
-
-ContentAddress LocalStore::hashCAPath(
-    const ContentAddressMethod & method,
-    const HashAlgorithm & hashAlgo,
-    const Path & path,
-    const std::string_view pathHash
-)
-{
-    HashModuloSink caSink ( hashAlgo, std::string(pathHash) );
-    std::visit(overloaded {
-        [&](const TextIngestionMethod &) {
-            readFile(path, caSink);
-        },
-        [&](const FileIngestionMethod & m2) {
-            switch (m2) {
-            case FileIngestionMethod::Recursive:
-                dumpPath(path, caSink);
-                break;
-            case FileIngestionMethod::Flat:
-                readFile(path, caSink);
-                break;
-            }
-        },
-    }, method.raw);
-    return ContentAddress {
-        .method = method,
-        .hash = caSink.finish().first,
-    };
-}
-
 void LocalStore::addBuildLog(const StorePath & drvPath, std::string_view log)
 {
     assert(drvPath.isDerivation());

src/libstore/local-store.hh

@@ -177,12 +177,11 @@ public:
     void addToStore(const ValidPathInfo & info, Source & source,
         RepairFlag repair, CheckSigsFlag checkSigs) override;
 
-    StorePath addToStoreFromDump(Source & dump, std::string_view name,
+    StorePath addToStoreFromDump(
-                                 FileIngestionMethod method, HashAlgorithm hashAlgo, RepairFlag repair, const StorePathSet & references) override;
+        Source & dump,
-
-    StorePath addTextToStore(
         std::string_view name,
-        std::string_view s,
+        ContentAddressMethod method,
+        HashAlgorithm hashAlgo,
         const StorePathSet & references,
         RepairFlag repair) override;
 
@@ -350,19 +349,6 @@ private:
     void signPathInfo(ValidPathInfo & info);
     void signRealisation(Realisation &);
 
-    // XXX: Make a generic `Store` method
-    ContentAddress hashCAPath(
-        const ContentAddressMethod & method,
-        const HashAlgorithm & hashAlgo,
-        const StorePath & path);
-
-    ContentAddress hashCAPath(
-        const ContentAddressMethod & method,
-        const HashAlgorithm & hashAlgo,
-        const Path & path,
-        const std::string_view pathHash
-    );
-
     void addBuildLog(const StorePath & drvPath, std::string_view log) override;
 
     friend struct LocalDerivationGoal;

src/libstore/optimise-store.cc

@@ -2,6 +2,7 @@
 #include "globals.hh"
 #include "signals.hh"
 #include "posix-fs-canonicalise.hh"
+#include "posix-source-accessor.hh"
 
 #include <cstdlib>
 #include <cstring>
@@ -146,7 +147,12 @@ void LocalStore::optimisePath_(Activity * act, OptimiseStats & stats,
        Also note that if `path' is a symlink, then we're hashing the
        contents of the symlink (i.e. the result of readlink()), not
        the contents of the target (which may not even exist). */
-    Hash hash = hashPath(HashAlgorithm::SHA256, path).first;
+    Hash hash = ({
+        PosixSourceAccessor accessor;
+        hashPath(
+            accessor, CanonPath { path },
+            FileIngestionMethod::Recursive, HashAlgorithm::SHA256).first;
+    });
     debug("'%1%' has hash '%2%'", path, hash.to_string(HashFormat::Nix32, true));
 
     /* Check if this is a known hash. */
@@ -156,7 +162,12 @@ void LocalStore::optimisePath_(Activity * act, OptimiseStats & stats,
     if (pathExists(linkPath)) {
         auto stLink = lstat(linkPath);
         if (st.st_size != stLink.st_size
-            || (repair && hash != hashPath(HashAlgorithm::SHA256, linkPath).first))
+            || (repair && hash != ({
+                PosixSourceAccessor accessor;
+                hashPath(
+                    accessor, CanonPath { linkPath },
+                    FileIngestionMethod::Recursive, HashAlgorithm::SHA256).first;
+           })))
         {
             // XXX: Consider overwriting linkPath with our valid version.
             warn("removing corrupted link '%s'", linkPath);

src/libstore/remote-store.cc

@@ -502,8 +502,13 @@ ref<const ValidPathInfo> RemoteStore::addCAToStore(
 }
 
 
-StorePath RemoteStore::addToStoreFromDump(Source & dump, std::string_view name,
+StorePath RemoteStore::addToStoreFromDump(
-                                          FileIngestionMethod method, HashAlgorithm hashAlgo, RepairFlag repair, const StorePathSet & references)
+    Source & dump,
+    std::string_view name,
+    ContentAddressMethod method,
+    HashAlgorithm hashAlgo,
+    const StorePathSet & references,
+    RepairFlag repair)
 {
     return addCAToStore(dump, name, method, hashAlgo, references, repair)->path;
 }
@@ -603,16 +608,6 @@ void RemoteStore::addMultipleToStore(
 }
 
 
-StorePath RemoteStore::addTextToStore(
-    std::string_view name,
-    std::string_view s,
-    const StorePathSet & references,
-    RepairFlag repair)
-{
-    StringSource source(s);
-    return addCAToStore(source, name, TextIngestionMethod {}, HashAlgorithm::SHA256, references, repair)->path;
-}
-
 void RemoteStore::registerDrvOutput(const Realisation & info)
 {
     auto conn(getConnection());

src/libstore/remote-store.hh

@@ -82,10 +82,15 @@ public:
             RepairFlag repair);
 
     /**
-     * Add a content-addressable store path. Does not support references. `dump` will be drained.
+     * Add a content-addressable store path. `dump` will be drained.
      */
-    StorePath addToStoreFromDump(Source & dump, std::string_view name,
+    StorePath addToStoreFromDump(
-                                 FileIngestionMethod method = FileIngestionMethod::Recursive, HashAlgorithm hashAlgo = HashAlgorithm::SHA256, RepairFlag repair = NoRepair, const StorePathSet & references = StorePathSet()) override;
+        Source & dump,
+        std::string_view name,
+        ContentAddressMethod method = FileIngestionMethod::Recursive,
+        HashAlgorithm hashAlgo = HashAlgorithm::SHA256,
+        const StorePathSet & references = StorePathSet(),
+        RepairFlag repair = NoRepair) override;
 
     void addToStore(const ValidPathInfo & info, Source & nar,
         RepairFlag repair, CheckSigsFlag checkSigs) override;
@@ -101,12 +106,6 @@ public:
         RepairFlag repair,
         CheckSigsFlag checkSigs) override;
 
-    StorePath addTextToStore(
-        std::string_view name,
-        std::string_view s,
-        const StorePathSet & references,
-        RepairFlag repair) override;
-
     void registerDrvOutput(const Realisation & info) override;
 
     void queryRealisationUncached(const DrvOutput &,

src/libstore/store-api.cc

@@ -205,25 +205,19 @@ StorePath StoreDirConfig::makeFixedOutputPath(std::string_view name, const Fixed
 }
 
 
-StorePath StoreDirConfig::makeTextPath(std::string_view name, const TextInfo & info) const
-{
-    assert(info.hash.algo == HashAlgorithm::SHA256);
-    return makeStorePath(
-        makeType(*this, "text", StoreReferences {
-            .others = info.references,
-            .self = false,
-        }),
-        info.hash,
-        name);
-}
-
-
 StorePath StoreDirConfig::makeFixedOutputPathFromCA(std::string_view name, const ContentAddressWithReferences & ca) const
 {
     // New template
     return std::visit(overloaded {
         [&](const TextInfo & ti) {
-            return makeTextPath(name, ti);
+            assert(ti.hash.algo == HashAlgorithm::SHA256);
+            return makeStorePath(
+                makeType(*this, "text", StoreReferences {
+                    .others = ti.references,
+                    .self = false,
+                }),
+                ti.hash,
+                name);
         },
         [&](const FixedOutputInfo & foi) {
             return makeFixedOutputPath(name, foi);
@@ -232,54 +226,45 @@ StorePath StoreDirConfig::makeFixedOutputPathFromCA(std::string_view name, const
 }
 
 
-std::pair<StorePath, Hash> StoreDirConfig::computeStorePathFromDump(
+std::pair<StorePath, Hash> StoreDirConfig::computeStorePath(
-        Source & dump,
     std::string_view name,
-        FileIngestionMethod method,
+    SourceAccessor & accessor,
+    const CanonPath & path,
+    ContentAddressMethod method,
     HashAlgorithm hashAlgo,
-        const StorePathSet & references) const
+    const StorePathSet & references,
+    PathFilter & filter) const
 {
-    HashSink sink(hashAlgo);
+    auto h = hashPath(accessor, path, method.getFileIngestionMethod(), hashAlgo, filter).first;
-    dump.drainInto(sink);
+    return {
-    auto h = sink.finish().first;
+        makeFixedOutputPathFromCA(
-    FixedOutputInfo caInfo {
+            name,
-        .method = method,
+            ContentAddressWithReferences::fromParts(
-        .hash = h,
+                method,
-        .references = {},
+                h,
+                {
+                    .others = references,
+                    .self = false,
+                })),
+        h,
     };
-    return std::make_pair(makeFixedOutputPath(name, caInfo), h);
-}
-
-
-StorePath StoreDirConfig::computeStorePathForText(
-    std::string_view name,
-    std::string_view s,
-    const StorePathSet & references) const
-{
-    return makeTextPath(name, TextInfo {
-        .hash = hashString(HashAlgorithm::SHA256, s),
-        .references = references,
-    });
 }
 
 
 StorePath Store::addToStore(
     std::string_view name,
-        const Path & _srcPath,
+    SourceAccessor & accessor,
-        FileIngestionMethod method,
+    const CanonPath & path,
+    ContentAddressMethod method,
     HashAlgorithm hashAlgo,
+    const StorePathSet & references,
     PathFilter & filter,
-        RepairFlag repair,
+    RepairFlag repair)
-        const StorePathSet & references)
 {
-    Path srcPath(absPath(_srcPath));
     auto source = sinkToSource([&](Sink & sink) {
-        if (method == FileIngestionMethod::Recursive)
+        dumpPath(accessor, path, sink, method.getFileIngestionMethod(), filter);
-            dumpPath(srcPath, sink, filter);
-        else
-            readFile(srcPath, sink);
     });
-    return addToStoreFromDump(*source, name, method, hashAlgo, repair, references);
+    return addToStoreFromDump(*source, name, method, hashAlgo, references, repair);
 }
 
 void Store::addMultipleToStore(
@@ -404,8 +389,12 @@ digraph graphname {
     fileSink -> caHashSink
 }
 */
-ValidPathInfo Store::addToStoreSlow(std::string_view name, const Path & srcPath,
+ValidPathInfo Store::addToStoreSlow(
-                                    FileIngestionMethod method, HashAlgorithm hashAlgo,
+    std::string_view name,
+    SourceAccessor & accessor,
+    const CanonPath & srcPath,
+    ContentAddressMethod method, HashAlgorithm hashAlgo,
+    const StorePathSet & references,
     std::optional<Hash> expectedCAHash)
 {
     HashSink narHashSink { HashAlgorithm::SHA256 };
@@ -425,7 +414,7 @@ ValidPathInfo Store::addToStoreSlow(std::string_view name, const Path & srcPath,
        srcPath. The fact that we use scratchpadSink as a temporary buffer here
        is an implementation detail. */
     auto fileSource = sinkToSource([&](Sink & scratchpadSink) {
-        dumpPath(srcPath, scratchpadSink);
+        accessor.dumpPath(srcPath, scratchpadSink);
     });
 
     /* tapped provides the same data as fileSource, but we also write all the
@@ -433,9 +422,11 @@ ValidPathInfo Store::addToStoreSlow(std::string_view name, const Path & srcPath,
     TeeSource tapped { *fileSource, narSink };
 
     NullParseSink blank;
-    auto & parseSink = method == FileIngestionMethod::Flat
+    auto & parseSink = method.getFileIngestionMethod() == FileIngestionMethod::Flat
         ? (ParseSink &) fileSink
-        : (ParseSink &) blank;
+        : method.getFileIngestionMethod() == FileIngestionMethod::Recursive
+        ? (ParseSink &) blank
+        : (abort(), (ParseSink &)*(ParseSink *)nullptr); // handled both cases
 
     /* The information that flows from tapped (besides being replicated in
        narSink), is now put in parseSink. */
@@ -452,21 +443,24 @@ ValidPathInfo Store::addToStoreSlow(std::string_view name, const Path & srcPath,
     if (expectedCAHash && expectedCAHash != hash)
         throw Error("hash mismatch for '%s'", srcPath);
 
+
     ValidPathInfo info {
         *this,
         name,
-        FixedOutputInfo {
+        ContentAddressWithReferences::fromParts(
-            .method = method,
+            method,
-            .hash = hash,
+            hash,
-            .references = {},
+            {
-        },
+                .others = references,
+                .self = false,
+            }),
         narHash,
     };
     info.narSize = narSize;
 
     if (!isValidPath(info.path)) {
         auto source = sinkToSource([&](Sink & scratchpadSink) {
-            dumpPath(srcPath, scratchpadSink);
+            accessor.dumpPath(srcPath, scratchpadSink);
         });
         addToStore(info, *source);
     }

src/libstore/store-api.hh

@@ -428,20 +428,26 @@ public:
      */
     virtual StorePath addToStore(
         std::string_view name,
-            const Path & srcPath,
+        SourceAccessor & accessor,
-            FileIngestionMethod method = FileIngestionMethod::Recursive,
+        const CanonPath & path,
+        ContentAddressMethod method = FileIngestionMethod::Recursive,
         HashAlgorithm hashAlgo = HashAlgorithm::SHA256,
+        const StorePathSet & references = StorePathSet(),
         PathFilter & filter = defaultPathFilter,
-            RepairFlag repair = NoRepair,
+        RepairFlag repair = NoRepair);
-            const StorePathSet & references = StorePathSet());
 
     /**
      * Copy the contents of a path to the store and register the
      * validity the resulting path, using a constant amount of
      * memory.
      */
-    ValidPathInfo addToStoreSlow(std::string_view name, const Path & srcPath,
+    ValidPathInfo addToStoreSlow(
-                                 FileIngestionMethod method = FileIngestionMethod::Recursive, HashAlgorithm hashAlgo = HashAlgorithm::SHA256,
+        std::string_view name,
+        SourceAccessor & accessor,
+        const CanonPath & path,
+        ContentAddressMethod method = FileIngestionMethod::Recursive,
+        HashAlgorithm hashAlgo = HashAlgorithm::SHA256,
+        const StorePathSet & references = StorePathSet(),
         std::optional<Hash> expectedCAHash = {});
 
     /**
@@ -453,20 +459,14 @@ public:
      *
      * \todo remove?
      */
-    virtual StorePath addToStoreFromDump(Source & dump, std::string_view name,
+    virtual StorePath addToStoreFromDump(
-                                         FileIngestionMethod method = FileIngestionMethod::Recursive, HashAlgorithm hashAlgo = HashAlgorithm::SHA256, RepairFlag repair = NoRepair,
+        Source & dump,
-                                         const StorePathSet & references = StorePathSet())
-    { unsupported("addToStoreFromDump"); }
-
-    /**
-     * Like addToStore, but the contents written to the output path is a
-     * regular file containing the given string.
-     */
-    virtual StorePath addTextToStore(
         std::string_view name,
-        std::string_view s,
+        ContentAddressMethod method = FileIngestionMethod::Recursive,
-        const StorePathSet & references,
+        HashAlgorithm hashAlgo = HashAlgorithm::SHA256,
-        RepairFlag repair = NoRepair) = 0;
+        const StorePathSet & references = StorePathSet(),
+        RepairFlag repair = NoRepair)
+    { unsupported("addToStoreFromDump"); }
 
     /**
      * Add a mapping indicating that `deriver!outputName` maps to the output path

src/libstore/store-dir-config.hh

@@ -86,41 +86,20 @@ struct StoreDirConfig : public Config
 
     StorePath makeFixedOutputPath(std::string_view name, const FixedOutputInfo & info) const;
 
-    StorePath makeTextPath(std::string_view name, const TextInfo & info) const;
-
     StorePath makeFixedOutputPathFromCA(std::string_view name, const ContentAddressWithReferences & ca) const;
 
     /**
-     * Read-only variant of addToStoreFromDump(). It returns the store
+     * Read-only variant of addToStore(). It returns the store
-     * path to which a NAR or flat file would be written.
+     * path for the given file sytem object.
      */
-    std::pair<StorePath, Hash> computeStorePathFromDump(
+    std::pair<StorePath, Hash> computeStorePath(
-        Source & dump,
         std::string_view name,
-        FileIngestionMethod method = FileIngestionMethod::Recursive,
+        SourceAccessor & accessor,
+        const CanonPath & path,
+        ContentAddressMethod method = FileIngestionMethod::Recursive,
         HashAlgorithm hashAlgo = HashAlgorithm::SHA256,
-        const StorePathSet & references = {}) const;
+        const StorePathSet & references = {},
-
+        PathFilter & filter = defaultPathFilter) const;
-    /**
-     * Preparatory part of addTextToStore().
-     *
-     * !!! Computation of the path should take the references given to
-     * addTextToStore() into account, otherwise we have a (relatively
-     * minor) security hole: a caller can register a source file with
-     * bogus references.  If there are too many references, the path may
-     * not be garbage collected when it has to be (not really a problem,
-     * the caller could create a root anyway), or it may be garbage
-     * collected when it shouldn't be (more serious).
-     *
-     * Hashing the references would solve this (bogus references would
-     * simply yield a different store path, so other users wouldn't be
-     * affected), but it has some backwards compatibility issues (the
-     * hashing scheme changes), so I'm not doing that for now.
-     */
-    StorePath computeStorePathForText(
-        std::string_view name,
-        std::string_view s,
-        const StorePathSet & references) const;
 };
 
 }

src/libutil/error.cc

@@ -173,10 +173,9 @@ static bool printUnknownLocations = getEnv("_NIX_EVAL_SHOW_UNKNOWN_LOCATIONS").h
 static bool printPosMaybe(std::ostream & oss, std::string_view indent, const std::shared_ptr<AbstractPos> & pos) {
     bool hasPos = pos && *pos;
     if (hasPos) {
-        oss << "\n" << indent << ANSI_BLUE << "at " ANSI_WARNING << *pos << ANSI_NORMAL << ":";
+        oss << indent << ANSI_BLUE << "at " ANSI_WARNING << *pos << ANSI_NORMAL << ":";
 
         if (auto loc = pos->getCodeLines()) {
-            oss << "\n";
             printCodeLines(oss, "", *pos, *loc);
             oss << "\n";
         }

src/libutil/file-content-address.cc

@@ -0,0 +1,49 @@
+#include "file-content-address.hh"
+#include "archive.hh"
+
+namespace nix {
+
+void dumpPath(
+    SourceAccessor & accessor, const CanonPath & path,
+    Sink & sink,
+    FileIngestionMethod method,
+    PathFilter & filter)
+{
+    switch (method) {
+    case FileIngestionMethod::Flat:
+        accessor.readFile(path, sink);
+        break;
+    case FileIngestionMethod::Recursive:
+        accessor.dumpPath(path, sink, filter);
+        break;
+    }
+}
+
+
+void restorePath(
+    const Path & path,
+    Source & source,
+    FileIngestionMethod method)
+{
+    switch (method) {
+    case FileIngestionMethod::Flat:
+        writeFile(path, source);
+        break;
+    case FileIngestionMethod::Recursive:
+        restorePath(path, source);
+        break;
+    }
+}
+
+
+HashResult hashPath(
+    SourceAccessor & accessor, const CanonPath & path,
+    FileIngestionMethod method, HashAlgorithm ht,
+    PathFilter & filter)
+{
+    HashSink sink { ht };
+    dumpPath(accessor, path, sink, method, filter);
+    return sink.finish();
+}
+
+}

src/libutil/file-content-address.hh

@@ -0,0 +1,56 @@
+#pragma once
+///@file
+
+#include "source-accessor.hh"
+#include "fs-sink.hh"
+#include "util.hh"
+
+namespace nix {
+
+/**
+ * An enumeration of the main ways we can serialize file system
+ * objects.
+ */
+enum struct FileIngestionMethod : uint8_t {
+    /**
+     * Flat-file hashing. Directly ingest the contents of a single file
+     */
+    Flat = 0,
+    /**
+     * Recursive (or NAR) hashing. Serializes the file-system object in
+     * Nix Archive format and ingest that.
+     */
+    Recursive = 1,
+};
+
+/**
+ * Dump a serialization of the given file system object.
+ */
+void dumpPath(
+    SourceAccessor & accessor, const CanonPath & path,
+    Sink & sink,
+    FileIngestionMethod method,
+    PathFilter & filter = defaultPathFilter);
+
+/**
+ * Restore a serialization of the given file system object.
+ *
+ * @TODO use an arbitrary `ParseSink`.
+ */
+void restorePath(
+    const Path & path,
+    Source & source,
+    FileIngestionMethod method);
+
+/**
+ * Compute the hash of the given file system object according to the
+ * given method.
+ *
+ * The hash is defined as (essentially) hashString(ht, dumpPath(path)).
+ */
+HashResult hashPath(
+    SourceAccessor & accessor, const CanonPath & path,
+    FileIngestionMethod method, HashAlgorithm ht,
+    PathFilter & filter = defaultPathFilter);
+
+}

src/libutil/hash.cc

@@ -367,15 +367,6 @@ HashResult HashSink::currentHash()
 }
 
 
-HashResult hashPath(
-        HashAlgorithm ha, const Path & path, PathFilter & filter)
-{
-    HashSink sink(ha);
-    dumpPath(path, sink, filter);
-    return sink.finish();
-}
-
-
 Hash compressHash(const Hash & hash, unsigned int newSize)
 {
     Hash h(hash.algo);

src/libutil/hash.hh

@@ -168,14 +168,11 @@ Hash hashString(HashAlgorithm ha, std::string_view s);
 Hash hashFile(HashAlgorithm ha, const Path & path);
 
 /**
- * Compute the hash of the given path, serializing as a Nix Archive and
+ * The final hash and the number of bytes digested.
- * then hashing that.
  *
- * The hash is defined as (essentially) hashString(ht, dumpPath(path)).
+ * @todo Convert to proper struct
  */
 typedef std::pair<Hash, uint64_t> HashResult;
-HashResult hashPath(HashAlgorithm ha, const Path & path,
-                    PathFilter & filter = defaultPathFilter);
 
 /**
  * Compress a hash to the specified number of bytes by cyclically

src/libutil/url-parts.hh

@@ -19,13 +19,15 @@ const static std::string userRegex = "(?:(?:" + unreservedRegex + "|" + pctEncod
 const static std::string authorityRegex = "(?:" + userRegex + "@)?" + hostRegex + "(?::[0-9]+)?";
 const static std::string pcharRegex = "(?:" + unreservedRegex + "|" + pctEncoded + "|" + subdelimsRegex + "|[:@])";
 const static std::string queryRegex = "(?:" + pcharRegex + "|[/? \"])*";
+const static std::string fragmentRegex = "(?:" + pcharRegex + "|[/? \"^])*";
 const static std::string segmentRegex = "(?:" + pcharRegex + "*)";
 const static std::string absPathRegex = "(?:(?:/" + segmentRegex + ")*/?)";
 const static std::string pathRegex = "(?:" + segmentRegex + "(?:/" + segmentRegex + ")*/?)";
 
 /// A Git ref (i.e. branch or tag name).
 /// \todo check that this is correct.
-const static std::string refRegexS = "[a-zA-Z0-9@][a-zA-Z0-9_.\\/@-]*";
+/// This regex incomplete. See https://git-scm.com/docs/git-check-ref-format
+const static std::string refRegexS = "[a-zA-Z0-9@][a-zA-Z0-9_.\\/@+-]*";
 extern std::regex refRegex;
 
 /// Instead of defining what a good Git Ref is, we define what a bad Git Ref is

src/libutil/url.cc

@@ -16,7 +16,7 @@ ParsedURL parseURL(const std::string & url)
         "((" + schemeNameRegex + "):"
         + "(?:(?://(" + authorityRegex + ")(" + absPathRegex + "))|(/?" + pathRegex + ")))"
         + "(?:\\?(" + queryRegex + "))?"
-        + "(?:#(" + queryRegex + "))?",
+        + "(?:#(" + fragmentRegex + "))?",
         std::regex::ECMAScript);
 
     std::smatch match;

src/nix-env/user-env.cc

@@ -104,10 +104,15 @@ bool createUserEnv(EvalState & state, DrvInfos & elems,
     /* Also write a copy of the list of user environment elements to
        the store; we need it for future modifications of the
        environment. */
+    auto manifestFile = ({
         std::ostringstream str;
         manifest.print(state.symbols, str, true);
-    auto manifestFile = state.store->addTextToStore("env-manifest.nix",
+        // TODO with C++20 we can use str.view() instead and avoid copy.
-        str.str(), references);
+        std::string str2 = str.str();
+        StringSource source { str2 };
+        state.store->addToStoreFromDump(
+            source, "env-manifest.nix", TextIngestionMethod {}, HashAlgorithm::SHA256, references);
+    });
 
     /* Get the environment builder expression. */
     Value envBuilder;

src/nix-store/nix-store.cc

@@ -13,6 +13,7 @@
 #include "shared.hh"
 #include "graphml.hh"
 #include "legacy.hh"
+#include "posix-source-accessor.hh"
 #include "path-with-outputs.hh"
 #include "posix-fs-canonicalise.hh"
 
@@ -175,8 +176,12 @@ static void opAdd(Strings opFlags, Strings opArgs)
 {
     if (!opFlags.empty()) throw UsageError("unknown flag");
 
+    PosixSourceAccessor accessor;
     for (auto & i : opArgs)
-        cout << fmt("%s\n", store->printStorePath(store->addToStore(std::string(baseNameOf(i)), i)));
+        cout << fmt("%s\n", store->printStorePath(store->addToStore(
+            std::string(baseNameOf(i)),
+            accessor,
+            CanonPath::fromCwd(i))));
 }
 
 
@@ -196,8 +201,14 @@ static void opAddFixed(Strings opFlags, Strings opArgs)
     HashAlgorithm hashAlgo = parseHashAlgo(opArgs.front());
     opArgs.pop_front();
 
+    PosixSourceAccessor accessor;
     for (auto & i : opArgs)
-        std::cout << fmt("%s\n", store->printStorePath(store->addToStoreSlow(baseNameOf(i), i, method, hashAlgo).path));
+        std::cout << fmt("%s\n", store->printStorePath(store->addToStoreSlow(
+            baseNameOf(i),
+            accessor,
+            CanonPath::fromCwd(i),
+            method,
+            hashAlgo).path));
 }
 
 
@@ -541,7 +552,10 @@ static void registerValidity(bool reregister, bool hashGiven, bool canonicalise)
             if (canonicalise)
                 canonicalisePathMetaData(store->printStorePath(info->path), {});
             if (!hashGiven) {
-                HashResult hash = hashPath(HashAlgorithm::SHA256, store->printStorePath(info->path));
+                HashResult hash = hashPath(
+                    *store->getFSAccessor(false), CanonPath { store->printStorePath(info->path) },
+
+                    FileIngestionMethod::Recursive, HashAlgorithm::SHA256);
                 info->narHash = hash.first;
                 info->narSize = hash.second;
             }

src/nix/add-to-store.cc

@@ -2,6 +2,7 @@
 #include "common-args.hh"
 #include "store-api.hh"
 #include "archive.hh"
+#include "posix-source-accessor.hh"
 
 using namespace nix;
 
@@ -20,7 +21,7 @@ struct CmdAddToStore : MixDryRun, StoreCommand
 {
     Path path;
     std::optional<std::string> namePart;
-    FileIngestionMethod ingestionMethod = FileIngestionMethod::Recursive;
+    ContentAddressMethod caMethod = FileIngestionMethod::Recursive;
 
     CmdAddToStore()
     {
@@ -48,7 +49,7 @@ struct CmdAddToStore : MixDryRun, StoreCommand
             )",
             .labels = {"hash-mode"},
             .handler = {[this](std::string s) {
-                this->ingestionMethod = parseIngestionMethod(s);
+                this->caMethod = parseIngestionMethod(s);
             }},
         });
     }
@@ -57,36 +58,17 @@ struct CmdAddToStore : MixDryRun, StoreCommand
     {
         if (!namePart) namePart = baseNameOf(path);
 
-        StringSink sink;
+        PosixSourceAccessor accessor;
-        dumpPath(path, sink);
 
-        auto narHash = hashString(HashAlgorithm::SHA256, sink.s);
+        auto path2 = CanonPath::fromCwd(path);
 
-        Hash hash = narHash;
+        auto storePath = dryRun
-        if (ingestionMethod == FileIngestionMethod::Flat) {
+            ? store->computeStorePath(
-            HashSink hsink(HashAlgorithm::SHA256);
+                *namePart, accessor, path2, caMethod, HashAlgorithm::SHA256, {}).first
-            readFile(path, hsink);
+            : store->addToStoreSlow(
-            hash = hsink.finish().first;
+                *namePart, accessor, path2, caMethod, HashAlgorithm::SHA256, {}).path;
-        }
 
-        ValidPathInfo info {
+        logger->cout("%s", store->printStorePath(storePath));
-            *store,
-            std::move(*namePart),
-            FixedOutputInfo {
-                .method = std::move(ingestionMethod),
-                .hash = std::move(hash),
-                .references = {},
-            },
-            narHash,
-        };
-        info.narSize = sink.s.size();
-
-        if (!dryRun) {
-            auto source = StringSource(sink.s);
-            store->addToStore(info, source);
-        }
-
-        logger->cout("%s", store->printStorePath(info.path));
     }
 };
 
@@ -110,7 +92,7 @@ struct CmdAddFile : CmdAddToStore
 {
     CmdAddFile()
     {
-        ingestionMethod = FileIngestionMethod::Flat;
+        caMethod = FileIngestionMethod::Flat;
     }
 
     std::string description() override

src/nix/develop.cc

@@ -223,7 +223,11 @@ static StorePath getDerivationEnvironment(ref<Store> store, ref<Store> evalStore
     if (builder != "bash")
         throw Error("'nix develop' only works on derivations that use 'bash' as their builder");
 
-    auto getEnvShPath = evalStore->addTextToStore("get-env.sh", getEnvSh, {});
+    auto getEnvShPath = ({
+        StringSource source { getEnvSh };
+        evalStore->addToStoreFromDump(
+            source, "get-env.sh", TextIngestionMethod {}, HashAlgorithm::SHA256, {});
+    });
 
     drv.args = {store->printStorePath(getEnvShPath)};
 

src/nix/hash.cc

@@ -5,6 +5,7 @@
 #include "shared.hh"
 #include "references.hh"
 #include "archive.hh"
+#include "posix-source-accessor.hh"
 
 using namespace nix;
 
@@ -88,14 +89,8 @@ struct CmdHashBase : Command
             else
                 hashSink = std::make_unique<HashSink>(ha);
 
-            switch (mode) {
+            PosixSourceAccessor accessor;
-            case FileIngestionMethod::Flat:
+            dumpPath(accessor, CanonPath::fromCwd(path), *hashSink, mode);
-                readFile(path, *hashSink);
-                break;
-            case FileIngestionMethod::Recursive:
-                dumpPath(path, *hashSink);
-                break;
-            }
 
             Hash h = hashSink->finish().first;
             if (truncate && h.hashSize > 20) h = compressHash(h, 20);

src/nix/prefetch.cc

@@ -9,6 +9,7 @@
 #include "attr-path.hh"
 #include "eval-inline.hh"
 #include "legacy.hh"
+#include "posix-source-accessor.hh"
 
 #include <nlohmann/json.hpp>
 
@@ -122,7 +123,11 @@ std::tuple<StorePath, Hash> prefetchFile(
         Activity act(*logger, lvlChatty, actUnknown,
             fmt("adding '%s' to the store", url));
 
-        auto info = store->addToStoreSlow(*name, tmpFile, ingestionMethod, hashAlgo, expectedHash);
+        PosixSourceAccessor accessor;
+        auto info = store->addToStoreSlow(
+            *name,
+            accessor, CanonPath::fromCwd(tmpFile),
+            ingestionMethod, hashAlgo, {}, expectedHash);
         storePath = info.path;
         assert(info.ca);
         hash = info.ca->hash;

src/nix/profile-list.md

@@ -6,12 +6,14 @@ R""(
 
   ```console
   # nix profile list
+  Name:               gdb
   Index:              0
   Flake attribute:    legacyPackages.x86_64-linux.gdb
   Original flake URL: flake:nixpkgs
   Locked flake URL:   github:NixOS/nixpkgs/7b38b03d76ab71bdc8dc325e3f6338d984cc35ca
   Store paths:        /nix/store/indzcw5wvlhx6vwk7k4iq29q15chvr3d-gdb-11.1
 
+  Name:               blender-bin
   Index:              1
   Flake attribute:    packages.x86_64-linux.default
   Original flake URL: flake:blender-bin
@@ -26,7 +28,7 @@ R""(
   # nix build github:edolstra/nix-warez/91f2ffee657bf834e4475865ae336e2379282d34?dir=blender#packages.x86_64-linux.default
   ```
 
-  will build the package with index 1 shown above.
+  will build the package `blender-bin` shown above.
 
 # Description
 
@@ -34,10 +36,14 @@ This command shows what packages are currently installed in a
 profile. For each installed package, it shows the following
 information:
 
-* `Index`: An integer that can be used to unambiguously identify the
+* `Name`: A unique name used to unambiguously identify the
   package in invocations of `nix profile remove` and `nix profile
   upgrade`.
 
+* `Index`: An integer that can be used to unambiguously identify the
+  package in invocations of `nix profile remove` and `nix profile upgrade`.
+  (*Deprecated, will be removed in a future version in favor of `Name`.*)
+
 * `Flake attribute`: The flake output attribute path that provides the
   package (e.g. `packages.x86_64-linux.hello`).
 

src/nix/profile-remove.md

@@ -2,18 +2,19 @@ R""(
 
 # Examples
 
-* Remove a package by position:
+* Remove a package by name:
+
+  ```console
+  # nix profile remove hello
+  ```
+
+* Remove a package by index
+  *(deprecated, will be removed in a future version)*:
 
   ```console
   # nix profile remove 3
   ```
 
-* Remove a package by attribute path:
-
-  ```console
-  # nix profile remove packages.x86_64-linux.hello
-  ```
-
 * Remove all packages:
 
   ```console

src/nix/profile-upgrade.md

@@ -9,18 +9,16 @@ R""(
   # nix profile upgrade '.*'
   ```
 
-* Upgrade a specific package:
+* Upgrade a specific package by name:
 
   ```console
-  # nix profile upgrade packages.x86_64-linux.hello
+  # nix profile upgrade hello
   ```
 
-* Upgrade a specific profile element by number:
+* Upgrade a specific package by index
+  *(deprecated, will be removed in a future version)*:
 
   ```console
-  # nix profile list
-  0 flake:nixpkgs#legacyPackages.x86_64-linux.spotify …
-
   # nix profile upgrade 0
   ```
 

src/nix/profile.cc

@@ -10,6 +10,8 @@
 #include "../nix-env/user-env.hh"
 #include "profiles.hh"
 #include "names.hh"
+#include "url.hh"
+#include "flake/url-name.hh"
 
 #include <nlohmann/json.hpp>
 #include <regex>
@@ -43,6 +45,7 @@ const int defaultPriority = 5;
 struct ProfileElement
 {
     StorePathSet storePaths;
+    std::string name;
     std::optional<ProfileElementSource> source;
     bool active = true;
     int priority = defaultPriority;
@@ -116,6 +119,8 @@ struct ProfileManifest
 
         if (pathExists(manifestPath)) {
             auto json = nlohmann::json::parse(readFile(manifestPath));
+            /* Keep track of already found names to allow preventing duplicates. */
+            std::set<std::string> foundNames;
 
             auto version = json.value("version", 0);
             std::string sUrl;
@@ -149,6 +154,25 @@ struct ProfileManifest
                         e["outputs"].get<ExtendedOutputsSpec>()
                     };
                 }
+
+                std::string nameCandidate = element.identifier();
+                if (e.contains("name")) {
+                    nameCandidate = e["name"];
+                }
+                else if (element.source) {
+                    auto url = parseURL(element.source->to_string());
+                    auto name = getNameFromURL(url);
+                    if (name)
+                        nameCandidate = *name;
+                }
+
+                auto finalName = nameCandidate;
+                for (int i = 1; foundNames.contains(finalName); ++i) {
+                    finalName = nameCandidate + std::to_string(i);
+                }
+                element.name = finalName;
+                foundNames.insert(element.name);
+
                 elements.emplace_back(std::move(element));
             }
         }
@@ -163,6 +187,7 @@ struct ProfileManifest
             for (auto & drvInfo : drvInfos) {
                 ProfileElement element;
                 element.storePaths = {drvInfo.queryOutPath()};
+                element.name = element.identifier();
                 elements.emplace_back(std::move(element));
             }
         }
@@ -451,15 +476,25 @@ public:
     {
         std::vector<Matcher> res;
 
+        auto anyIndexMatchers = false;
+
         for (auto & s : _matchers) {
-            if (auto n = string2Int<size_t>(s))
+            if (auto n = string2Int<size_t>(s)) {
                 res.push_back(*n);
+                anyIndexMatchers = true;
+            }
             else if (store->isStorePath(s))
                 res.push_back(s);
             else
                 res.push_back(RegexPattern{s,std::regex(s, std::regex::extended | std::regex::icase)});
         }
 
+        if (anyIndexMatchers) {
+            warn("Indices are deprecated and will be removed in a future version!\n"
+                 "         Refer to packages by their `Name` as printed by `nix profile list`.\n"
+                 "         See https://github.com/NixOS/nix/issues/9171 for more information.");
+        }
+
         return res;
     }
 
@@ -471,8 +506,7 @@ public:
             } else if (auto path = std::get_if<Path>(&matcher)) {
                 if (element.storePaths.count(store.parseStorePath(*path))) return true;
             } else if (auto regex = std::get_if<RegexPattern>(&matcher)) {
-                if (element.source
+                if (std::regex_match(element.name, regex->reg))
-                    && std::regex_match(element.source->attrPath, regex->reg))
                     return true;
             }
         }
@@ -556,14 +590,32 @@ struct CmdProfileUpgrade : virtual SourceExprCommand, MixDefaultProfile, MixProf
         Installables installables;
         std::vector<size_t> indices;
 
+        auto matchedCount = 0;
         auto upgradedCount = 0;
 
         for (size_t i = 0; i < manifest.elements.size(); ++i) {
             auto & element(manifest.elements[i]);
-            if (element.source
+            if (!matches(*store, element, i, matchers)) {
-                && !element.source->originalRef.input.isLocked()
+                continue;
-                && matches(*store, element, i, matchers))
+            }
-            {
+
+            matchedCount++;
+
+            if (!element.source) {
+                warn(
+                    "Found package '%s', but it was not installed from a flake, so it can't be checked for upgrades!",
+                    element.identifier()
+                );
+                continue;
+            }
+            if (element.source->originalRef.input.isLocked()) {
+                warn(
+                    "Found package '%s', but it was installed from a locked flake reference so it can't be upgraded!",
+                    element.identifier()
+                );
+                continue;
+            }
+
             upgradedCount++;
 
             Activity act(*logger, lvlChatty, actUnknown,
@@ -601,9 +653,9 @@ struct CmdProfileUpgrade : virtual SourceExprCommand, MixDefaultProfile, MixProf
             installables.push_back(installable);
             indices.push_back(i);
         }
-        }
 
         if (upgradedCount == 0) {
+            if (matchedCount == 0) {
                 for (auto & matcher : matchers) {
                     if (const size_t * index = std::get_if<size_t>(&matcher)){
                         warn("'%d' is not a valid index", *index);
@@ -613,6 +665,9 @@ struct CmdProfileUpgrade : virtual SourceExprCommand, MixDefaultProfile, MixProf
                         warn("'%s' does not match any packages", regex->pattern);
                     }
                 }
+            } else {
+                warn("Found some packages but none of them could be upgraded.");
+            }
             warn ("Use 'nix profile list' to see the current profile.");
         }
 
@@ -657,9 +712,10 @@ struct CmdProfileList : virtual EvalCommand, virtual StoreCommand, MixDefaultPro
             for (size_t i = 0; i < manifest.elements.size(); ++i) {
                 auto & element(manifest.elements[i]);
                 if (i) logger->cout("");
-                logger->cout("Index:              " ANSI_BOLD "%s" ANSI_NORMAL "%s",
+                logger->cout("Name:               " ANSI_BOLD "%s" ANSI_NORMAL "%s",
-                    i,
+                    element.name,
                     element.active ? "" : " " ANSI_RED "(inactive)" ANSI_NORMAL);
+                logger->cout("Index:              %s", i);
                 if (element.source) {
                     logger->cout("Flake attribute:    %s%s", element.source->attrPath, element.source->outputs.to_string());
                     logger->cout("Original flake URL: %s", element.source->originalRef.to_string());

tests/functional/lang/eval-fail-abort.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'abort' builtin
-
          at /pwd/lang/eval-fail-abort.nix:1:14:
-
             1| if true then abort "this should fail" else 1
              |              ^
             2|

tests/functional/lang/eval-fail-addDrvOutputDependencies-empty-context.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'addDrvOutputDependencies' builtin
-
          at /pwd/lang/eval-fail-addDrvOutputDependencies-empty-context.nix:1:1:
-
             1| builtins.addDrvOutputDependencies ""
              | ^
             2|

tests/functional/lang/eval-fail-addDrvOutputDependencies-multi-elem-context.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'addDrvOutputDependencies' builtin
-
          at /pwd/lang/eval-fail-addDrvOutputDependencies-multi-elem-context.nix:18:4:
-
            17|
            18| in builtins.addDrvOutputDependencies combo-path
              |    ^

tests/functional/lang/eval-fail-addDrvOutputDependencies-wrong-element-kind.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'addDrvOutputDependencies' builtin
-
          at /pwd/lang/eval-fail-addDrvOutputDependencies-wrong-element-kind.nix:9:4:
-
             8|
             9| in builtins.addDrvOutputDependencies drv.outPath
              |    ^

tests/functional/lang/eval-fail-assert.err.exp

@@ -1,35 +1,27 @@
 error:
        … while evaluating the attribute 'body'
-
          at /pwd/lang/eval-fail-assert.nix:4:3:
-
             3|
             4|   body = x "x";
              |   ^
             5| }
 
        … from call site
-
          at /pwd/lang/eval-fail-assert.nix:4:10:
-
             3|
             4|   body = x "x";
              |          ^
             5| }
 
        … while calling 'x'
-
          at /pwd/lang/eval-fail-assert.nix:2:7:
-
             1| let {
             2|   x = arg: assert arg == "y"; 123;
              |       ^
             3|
 
        error: assertion '(arg == "y")' failed
-
        at /pwd/lang/eval-fail-assert.nix:2:12:
-
             1| let {
             2|   x = arg: assert arg == "y"; 123;
              |            ^

tests/functional/lang/eval-fail-attr-name-type.err.exp

@@ -1,17 +1,13 @@
 error:
        … while evaluating the attribute 'puppy."${key}"'
-
          at /pwd/lang/eval-fail-attr-name-type.nix:3:5:
-
             2|   attrs = {
             3|     puppy.doggy = {};
              |     ^
             4|   };
 
        … while evaluating an attribute name
-
          at /pwd/lang/eval-fail-attr-name-type.nix:7:17:
-
             6| in
             7|   attrs.puppy.${key}
              |                 ^

tests/functional/lang/eval-fail-bad-string-interpolation-1.err.exp

@@ -1,8 +1,6 @@
 error:
        … while evaluating a path segment
-
          at /pwd/lang/eval-fail-bad-string-interpolation-1.nix:1:2:
-
             1| "${x: x}"
              |  ^
             2|

tests/functional/lang/eval-fail-bad-string-interpolation-3.err.exp

@@ -1,8 +1,6 @@
 error:
        … while evaluating a path segment
-
          at /pwd/lang/eval-fail-bad-string-interpolation-3.nix:1:3:
-
             1| ''${x: x}''
              |   ^
             2|

tests/functional/lang/eval-fail-bad-string-interpolation-4.err.exp

@@ -1,8 +1,6 @@
 error:
        … while evaluating a path segment
-
          at /pwd/lang/eval-fail-bad-string-interpolation-4.nix:9:3:
-
             8| # The error message should not be too long.
             9| ''${pkgs}''
              |   ^

tests/functional/lang/eval-fail-blackhole.err.exp

@@ -1,17 +1,13 @@
 error:
        … while evaluating the attribute 'body'
-
          at /pwd/lang/eval-fail-blackhole.nix:2:3:
-
             1| let {
             2|   body = x;
              |   ^
             3|   x = y;
 
        error: infinite recursion encountered
-
        at /pwd/lang/eval-fail-blackhole.nix:3:7:
-
             2|   body = x;
             3|   x = y;
              |       ^

tests/functional/lang/eval-fail-call-primop.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'length' builtin
-
          at /pwd/lang/eval-fail-call-primop.nix:1:1:
-
             1| builtins.length 1
              | ^
             2|

tests/functional/lang/eval-fail-deepseq.err.exp

@@ -1,24 +1,18 @@
 error:
        … while calling the 'deepSeq' builtin
-
          at /pwd/lang/eval-fail-deepseq.nix:1:1:
-
             1| builtins.deepSeq { x = abort "foo"; } 456
              | ^
             2|
 
        … while evaluating the attribute 'x'
-
          at /pwd/lang/eval-fail-deepseq.nix:1:20:
-
             1| builtins.deepSeq { x = abort "foo"; } 456
              |                    ^
             2|
 
        … while calling the 'abort' builtin
-
          at /pwd/lang/eval-fail-deepseq.nix:1:24:
-
             1| builtins.deepSeq { x = abort "foo"; } 456
              |                        ^
             2|

tests/functional/lang/eval-fail-dup-dynamic-attrs.err.exp

@@ -1,17 +1,13 @@
 error:
        … while evaluating the attribute 'set'
-
          at /pwd/lang/eval-fail-dup-dynamic-attrs.nix:2:3:
-
             1| {
             2|   set = { "${"" + "b"}" = 1; };
              |   ^
             3|   set = { "${"b" + ""}" = 2; };
 
        error: dynamic attribute 'b' already defined at /pwd/lang/eval-fail-dup-dynamic-attrs.nix:2:11
-
        at /pwd/lang/eval-fail-dup-dynamic-attrs.nix:3:11:
-
             2|   set = { "${"" + "b"}" = 1; };
             3|   set = { "${"b" + ""}" = 2; };
              |           ^

tests/functional/lang/eval-fail-foldlStrict-strict-op-application.err.exp

@@ -1,35 +1,27 @@
 error:
        … while calling the 'foldl'' builtin
-
          at /pwd/lang/eval-fail-foldlStrict-strict-op-application.nix:2:1:
-
             1| # Tests that the result of applying op is forced even if the value is never used
             2| builtins.foldl'
              | ^
             3|   (_: f: f null)
 
        … while calling anonymous lambda
-
          at /pwd/lang/eval-fail-foldlStrict-strict-op-application.nix:3:7:
-
             2| builtins.foldl'
             3|   (_: f: f null)
              |       ^
             4|   null
 
        … from call site
-
          at /pwd/lang/eval-fail-foldlStrict-strict-op-application.nix:3:10:
-
             2| builtins.foldl'
             3|   (_: f: f null)
              |          ^
             4|   null
 
        … while calling anonymous lambda
-
          at /pwd/lang/eval-fail-foldlStrict-strict-op-application.nix:5:6:
-
             4|   null
             5|   [ (_: throw "Not the final value, but is still forced!") (_: 23) ]
              |      ^

tests/functional/lang/eval-fail-fromTOML-timestamps.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'fromTOML' builtin
-
          at /pwd/lang/eval-fail-fromTOML-timestamps.nix:1:1:
-
             1| builtins.fromTOML ''
              | ^
             2|   key = "value"

tests/functional/lang/eval-fail-hashfile-missing.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'toString' builtin
-
          at /pwd/lang/eval-fail-hashfile-missing.nix:4:3:
-
             3| in
             4|   toString (builtins.concatLists (map (hash: map (builtins.hashFile hash) paths) ["md5" "sha1" "sha256" "sha512"]))
              |   ^

tests/functional/lang/eval-fail-list.err.exp

@@ -1,8 +1,6 @@
 error:
        … while evaluating one of the elements to concatenate
-
          at /pwd/lang/eval-fail-list.nix:1:2:
-
             1| 8++1
              |  ^
             2|

tests/functional/lang/eval-fail-missing-arg.err.exp

@@ -1,16 +1,12 @@
 error:
        … from call site
-
          at /pwd/lang/eval-fail-missing-arg.nix:1:1:
-
             1| ({x, y, z}: x + y + z) {x = "foo"; z = "bar";}
              | ^
             2|
 
        error: function 'anonymous lambda' called without required argument 'y'
-
        at /pwd/lang/eval-fail-missing-arg.nix:1:2:
-
             1| ({x, y, z}: x + y + z) {x = "foo"; z = "bar";}
              |  ^
             2|

tests/functional/lang/eval-fail-not-throws.err.exp

@@ -1,16 +1,12 @@
 error:
        … in the argument of the not operator
-
          at /pwd/lang/eval-fail-not-throws.nix:1:4:
-
             1| ! (throw "uh oh!")
              |    ^
             2|
 
        … while calling the 'throw' builtin
-
          at /pwd/lang/eval-fail-not-throws.nix:1:4:
-
             1| ! (throw "uh oh!")
              |    ^
             2|

tests/functional/lang/eval-fail-path-slash.err.exp

@@ -1,7 +1,5 @@
 error: path has a trailing slash
-
        at /pwd/lang/eval-fail-path-slash.nix:6:12:
-
             5| # and https://nixos.org/nix-dev/2016-June/020829.html
             6| /nix/store/
              |            ^

tests/functional/lang/eval-fail-recursion.err.exp

@@ -1,16 +1,12 @@
 error:
        … in the right operand of the update (//) operator
-
          at /pwd/lang/eval-fail-recursion.nix:1:12:
-
             1| let a = {} // a; in a.foo
              |            ^
             2|
 
        error: infinite recursion encountered
-
        at /pwd/lang/eval-fail-recursion.nix:1:15:
-
             1| let a = {} // a; in a.foo
              |               ^
             2|

tests/functional/lang/eval-fail-remove.err.exp

@@ -1,17 +1,13 @@
 error:
        … while evaluating the attribute 'body'
-
          at /pwd/lang/eval-fail-remove.nix:4:3:
-
             3|
             4|   body = (removeAttrs attrs ["x"]).x;
              |   ^
             5| }
 
        error: attribute 'x' missing
-
        at /pwd/lang/eval-fail-remove.nix:4:10:
-
             3|
             4|   body = (removeAttrs attrs ["x"]).x;
              |          ^

tests/functional/lang/eval-fail-scope-5.err.exp

@@ -1,35 +1,27 @@
 error:
        … while evaluating the attribute 'body'
-
          at /pwd/lang/eval-fail-scope-5.nix:8:3:
-
             7|
             8|   body = f {};
              |   ^
             9|
 
        … from call site
-
          at /pwd/lang/eval-fail-scope-5.nix:8:10:
-
             7|
             8|   body = f {};
              |          ^
             9|
 
        … while calling 'f'
-
          at /pwd/lang/eval-fail-scope-5.nix:6:7:
-
             5|
             6|   f = {x ? y, y ? x}: x + y;
              |       ^
             7|
 
        error: infinite recursion encountered
-
        at /pwd/lang/eval-fail-scope-5.nix:6:12:
-
             5|
             6|   f = {x ? y, y ? x}: x + y;
              |            ^

tests/functional/lang/eval-fail-seq.err.exp

@@ -1,16 +1,12 @@
 error:
        … while calling the 'seq' builtin
-
          at /pwd/lang/eval-fail-seq.nix:1:1:
-
             1| builtins.seq (abort "foo") 2
              | ^
             2|
 
        … while calling the 'abort' builtin
-
          at /pwd/lang/eval-fail-seq.nix:1:15:
-
             1| builtins.seq (abort "foo") 2
              |               ^
             2|

tests/functional/lang/eval-fail-set.err.exp

@@ -1,7 +1,5 @@
 error: undefined variable 'x'
-
        at /pwd/lang/eval-fail-set.nix:1:3:
-
             1| 8.x
              |   ^
             2|

tests/functional/lang/eval-fail-substring.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'substring' builtin
-
          at /pwd/lang/eval-fail-substring.nix:1:1:
-
             1| builtins.substring (builtins.sub 0 1) 1 "x"
              | ^
             2|

tests/functional/lang/eval-fail-to-path.err.exp

@@ -1,8 +1,6 @@
 error:
        … while calling the 'toPath' builtin
-
          at /pwd/lang/eval-fail-to-path.nix:1:1:
-
             1| builtins.toPath "foo/bar"
              | ^
             2|

tests/functional/lang/eval-fail-toJSON.err.exp

@@ -1,25 +1,19 @@
 error:
        … while calling the 'toJSON' builtin
-
          at /pwd/lang/eval-fail-toJSON.nix:1:1:
-
             1| builtins.toJSON {
              | ^
             2|   a.b = [
 
        … while evaluating attribute 'a'
-
          at /pwd/lang/eval-fail-toJSON.nix:2:3:
-
             1| builtins.toJSON {
             2|   a.b = [
              |   ^
             3|     true
 
        … while evaluating attribute 'b'
-
          at /pwd/lang/eval-fail-toJSON.nix:2:3:
-
             1| builtins.toJSON {
             2|   a.b = [
              |   ^
@@ -28,27 +22,21 @@ error:
        … while evaluating list element at index 3
 
        … while evaluating attribute 'c'
-
          at /pwd/lang/eval-fail-toJSON.nix:7:7:
-
             6|     {
             7|       c.d = throw "hah no";
              |       ^
             8|     }
 
        … while evaluating attribute 'd'
-
          at /pwd/lang/eval-fail-toJSON.nix:7:7:
-
             6|     {
             7|       c.d = throw "hah no";
              |       ^
             8|     }
 
        … while calling the 'throw' builtin
-
          at /pwd/lang/eval-fail-toJSON.nix:7:13:
-
             6|     {
             7|       c.d = throw "hah no";
              |             ^

tests/functional/lang/eval-fail-undeclared-arg.err.exp

@@ -1,16 +1,12 @@
 error:
        … from call site
-
          at /pwd/lang/eval-fail-undeclared-arg.nix:1:1:
-
             1| ({x, z}: x + z) {x = "foo"; y = "bla"; z = "bar";}
              | ^
             2|
 
        error: function 'anonymous lambda' called with unexpected argument 'y'
-
        at /pwd/lang/eval-fail-undeclared-arg.nix:1:2:
-
             1| ({x, z}: x + z) {x = "foo"; y = "bla"; z = "bar";}
              |  ^
             2|

tests/functional/lang/eval-fail-using-set-as-attr-name.err.exp

@@ -1,8 +1,6 @@
 error:
        … while evaluating an attribute name
-
          at /pwd/lang/eval-fail-using-set-as-attr-name.nix:5:10:
-
             4| in
             5|   attr.${key}
              |          ^

tests/functional/lang/parse-fail-dup-attrs-1.err.exp

@@ -1,7 +1,5 @@
 error: attribute 'x' already defined at «stdin»:1:3
-
        at «stdin»:3:3:
-
             2|   y = 456;
             3|   x = 789;
              |   ^