The old `std::variant` is bad because we aren't adding a new case to
`FileIngestionMethod` so much as we are defining a separate concept ---
store object content addressing rather than file system object content
addressing. As such, it is more correct to just create a fresh
enumeration.
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
This is not really part of the evaluator: it is just an integration
between Boehm GC and Boost coroutines usable for any purpose. The
evaluator (merely) optionally uses it.
This re-enables support for older bwdgc versions without complicating
the code too much.
Coroutines generally only interfere with GC during source filtering,
so it's not too bad of a regression on older bdwgc.
This seems preferable over conditional compilation to enable the patch
etc; we've already spent a lot of complexity budget on this GC-coroutine
interaction...
Manually tested by printing to stderr in both branches (sp in os
stack, or not), and triggering a GC in a filterSource function,
e.g.:
let
generateTree = n: if n == 0 then "ha" else { left = generateTree (n - 1); right = generateTree (n - 1); };
in
builtins.deepSeq (generateTree 18) ...
Note that the darwin still uses the strategy of disabling GC, despite
having an implementation that compiles. The proper solution will be
enabled and tested later.
... so that we may perhaps later extend the interface.
Note that Nixpkgs' lib.warn already requires a string coercible
argument, so this is reasonable. Also note that string coercible
values aren't all strings, but in practice, for warn, they are.
* docs: mention importNative/exec in allow-unsafe-native-code-during-evaluation
Both of these still needs their own actual documentation, but they are
at least now mentioned that they exist and what they're enabled by.
Co-authored-by: Qyriad <qyriad@qyriad.me>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
In addition:
- Take the opportunity to add a bunch more missing hyperlinks, too.
- Remove some glossary entries that are now subsumed by dedicated pages.
We used to not be able to do this without breaking link fragments, but
now we can, so pick up where we left off.
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
* Document string context
Now what we have enough primops, we can document how string contexts
work.
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: Théophane Hufschmitt <7226587+thufschmitt@users.noreply.github.com>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
Co-authored-by: Felix Uhl <iFreilicht@users.noreply.github.com>
builtins.strictDerivation returns an attribute set with drvPath and
output paths. For some reason, current implementation forbids drv
instead of drvPath.
This was changed in #10611, which caused the derivation paths of
anything using builtin:fetchurl to change (i.e. all of
Nixpkgs). However, impureEnvVars doesn't actually do anything for
builtin:fetchurl, so we can just set it to its historical value.
Different parts of the project honor different sets of proxy environment
variables. With this commit all parts of the project will honor the same
set of proxy environment variables.
---------
Co-authored-by: Your Name <you@example.com>
Co-authored-by: John Ericson <John.Ericson@Obsidian.Systems>
After the removal of the InputAccessor::fetchToStore() method, the
only remaining functionality in InputAccessor was `fingerprint` and
`getLastModified()`, and there is no reason to keep those in a
separate class.
This missing GC root wasn't much of a problem before, because the
heap would end up with a reference to the `baseEnv` pretty soon,
but when unit testing, the construction of `EvalState` doesn't
necessarily happen well before GC runs for the first time.
Found while unit testing the Rust bindings that currently reside
at https://github.com/nixops4/nixops4/tree/main/rust
Add a method to check if a value has been initialized. This helps avoid
segfaults when calling `type()`.
Useful in the context of the new C API.
Closes#10524
At this point many features are stripped out, but this works:
- Can run libnix{util,store,expr} unit tests
- Can run some Nix commands
Co-Authored-By volth <volth@volth.com>
Co-Authored-By Brian McKenna <brian@brianmckenna.org>
Code operating on store objects (including creating them) should, in
general, use `ContentAddressMethod` rather than `FileIngestionMethod`.
See also dfc876531f which included some
similar refactors.
Now that we have a few things identifying content address methods by
name, we should be consistent about it.
Move up the `parseHashAlgoOpt` for tidiness too.
Discussed this change for consistency's sake as part of #8876
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
This was used in only one place, namely builtins.fetchurl with an
expected hash. Since this can cause similar issues as described
in #9814 and #9905 with the "locked" flag for fetchTarball and fetchTree,
let's just remove it.
Note that if an expected hash is given and the hash algorithm is
SHA-256, then we will never do a download anyway if the resulting
store path already exists. So removing the "locked" flag will only
cause potentially unnecessary HTTP requests (subject to the tarball
TTL) for non-SHA-256 hashes.
code blocks, if not surrounded by empty lines, have the language
tags (in these cases, always `nix`) show up in the output of :doc.
for example:
nix-repl> :doc builtins.parseFlakeRef
Synopsis: builtins.parseFlakeRef flake-ref
Parse a flake reference, and return its exploded form.
For example: nix builtins.parseFlakeRef
"github:NixOS/nixpkgs/23.05?dir=lib" evaluates to: nix { dir =
"lib"; owner = "NixOS"; ref = "23.05"; repo = "nixpkgs"; type =
"github"; }
is now instead:
nix-repl> :doc builtins.parseFlakeRef
Synopsis: builtins.parseFlakeRef flake-ref
Parse a flake reference, and return its exploded form.
For example:
| builtins.parseFlakeRef "github:NixOS/nixpkgs/23.05?dir=lib"
evaluates to:
| { dir = "lib"; owner = "NixOS"; ref = "23.05"; repo = "nixpkgs"; type = "github"; }
This was part of approved PR #10021. Unfortunately that one is stalled
on a peculiar Linux test timeout, so trying to get bits of it merged
first to bisect failure.
A possible use of them might have been to figure out the paths
(which can now be retrieved with maybePathsOut), but I have
not found evidence that it was used this way, and it would have
been broken, because non-CA outputs weren't recorded in the map.
Thunks are now overwritten by a helper function
`Value::finishValue(newType, payload)` (where `payload` is the
original anonymous union inside `Value`). This helps to ensure we
never update a value elsewhere, since that would be incompatible with
parallel evaluation (i.e. after a value has transitioned from being a
thunk to being a non-thunk, it should be immutable).
There were two places where this happened: `Value::mkString()` and
`ExprAttrs::eval()`.
This PR also adds a bunch of accessor functions for value contents,
like `Value::integer()` to access the integer field in the union.
Fixes
terminate called after throwing an instance of 'boost::wrapexcept<boost::io::too_few_args>'
what(): boost::too_few_args: format-string referred to more arguments than were passed
Aborted (core dumped)
for type errors in AttrCursor.
Previously, `state.mkList()` would set the type of the value to tList
and allocate the list vector, but it would not initialize the values
in the list. This has two problems:
* If an exception occurs, the list is left in an undefined state.
* More importantly, for multithreaded evaluation, if a value
transitions from thunk to non-thunk, it should be final (i.e. other
threads should be able to access the value safely).
To address this, there now is a `ListBuilder` class (analogous to
`BindingsBuilder`) to build the list vector prior to the call to
`Value::mkList()`. Typical usage:
auto list = state.buildList(size);
for (auto & v : list)
v = ... set value ...;
vRes.mkList(list);
Previously, errors while printing values in `nix repl` would be printed
in `«error: ...»` brackets rather than displayed normally:
```
nix-repl> legacyPackages.aarch64-darwin.pythonPackages.APScheduler
«error: Package ‘python-2.7.18.7’ in /nix/store/6s0m1qc31zw3l3kq0q4wd5cp3lqpkq0q-source/pkgs/development/interpreters/python/cpython/2.7/default.nix:335 is marked as insecure, refusing to evaluate.»
```
Now, errors will be displayed normally if they're emitted at the
top-level of an expression:
```
nix-repl> legacyPackages.aarch64-darwin.pythonPackages.APScheduler
error:
… in the condition of the assert statement
at /nix/store/6s0m1qc31zw3l3kq0q4wd5cp3lqpkq0q-source/lib/customisation.nix:268:17:
267| in commonAttrs // {
268| drvPath = assert condition; drv.drvPath;
| ^
269| outPath = assert condition; drv.outPath;
… in the left operand of the OR (||) operator
at /nix/store/6s0m1qc31zw3l3kq0q4wd5cp3lqpkq0q-source/pkgs/development/interpreters/python/passthrufun.nix:28:45:
27| if lib.isDerivation value then
28| lib.extendDerivation (valid value || throw "${name} should use `buildPythonPackage` or `toPythonModule` if it is to be part of the Python packages set.") {} value
| ^
29| else
(stack trace truncated; use '--show-trace' to show the full trace)
error: Package ‘python-2.7.18.7’ in /nix/store/6s0m1qc31zw3l3kq0q4wd5cp3lqpkq0q-source/pkgs/development/interpreters/python/cpython/2.7/default.nix:335 is marked as insecure, refusing to evaluate.
```
Errors emitted in nested structures (like e.g. when printing `nixpkgs`)
will still be printed in brackets.
