Commit graph

256 commits

Author SHA1 Message Date
Eelco Dolstra
81e7c40264 Optimize primop calls
We now parse function applications as a vector of arguments rather
than as a chain of binary applications, e.g. 'substring 1 2 "foo"' is
parsed as

  ExprCall { .fun = <substring>, .args = [ <1>, <2>, <"foo"> ] }

rather than

  ExprApp (ExprApp (ExprApp <substring> <1>) <2>) <"foo">

This allows primops to be called immediately (if enough arguments are
supplied) without having to allocate intermediate tPrimOpApp values.

On

  $ nix-instantiate --dry-run '<nixpkgs/nixos/release-combined.nix>' -A nixos.tests.simple.x86_64-linux

this gives a substantial performance improvement:

  user CPU time:      median =      0.9209  mean =      0.9218  stddev =      0.0073  min =      0.9086  max =      0.9340  [rejected, p=0.00000, Δ=-0.21433±0.00677]
  elapsed time:       median =      1.0585  mean =      1.0584  stddev =      0.0024  min =      1.0523  max =      1.0623  [rejected, p=0.00000, Δ=-0.20594±0.00236]

because it reduces the number of tPrimOpApp allocations from 551990 to
42534 (i.e. only small minority of primop calls are partially
applied) which in turn reduces time spent in the garbage collector.
2021-11-04 15:03:40 +01:00
Eelco Dolstra
ab35cbd675 StaticEnv: Use std::vector instead of std::map 2021-11-04 15:03:34 +01:00
Eelco Dolstra
5a160171d0 Remove redundant 'warning:' 2021-10-27 18:14:12 +02:00
regnat
af99941279 Make experimental-features a proper type
Rather than having them plain strings scattered through the whole
codebase, create an enum containing all the known experimental features.

This means that
- Nix can now `warn` when an unkwown experimental feature is passed
  (making it much nicer to spot typos and spot deprecated features)
- It’s now easy to remove a feature altogether (once the feature isn’t
  experimental anymore or is dropped) by just removing the field for the
  enum and letting the compiler point us to all the now invalid usages
  of it.
2021-10-26 07:02:31 +02:00
Ben Burdette
fb8377547b more code cleanup 2021-10-22 14:49:58 -06:00
Ben Burdette
e54f17eb46 remove more debug code 2021-10-22 14:27:04 -06:00
Ben Burdette
427fb8d158 comment out debugs 2021-10-11 16:48:10 -06:00
Andreas Rammhold
cae41eebff libexpr: remove matchAttrs boolean from ExprLambda
The boolean is only used to determine if the formals are set to a
non-null pointer in all our cases. We can get rid of that allocation and
instead just compare the pointer value with NULL. Saving up to
sizeof(bool) + platform specific alignment per ExprLambda instace.
Probably not a lot of memory but perhaps a few kilobyte with nixpkgs?

This also gets rid of a potential issue with dereferencing formals based on
the value of the boolean that didn't have to be aligned with the formals
pointer but was in all our cases.
2021-10-06 17:24:06 +02:00
Geoff Reedy
9d67332e4b Better eval error locations for interpolation and +
Previously, type or coercion errors for string interpolation, path
interpolation, and plus expressions were always reported at the
beginning of the outer expression. This leads to confusing evaluation
error messages making it hard to accurately diagnose and then fix the
error.

For example, errors were reported as follows.

```
cannot coerce an integer to a string
1| let foo = 7; in "bar" + foo
 |                 ^

cannot add a string to an integer
1| let foo = "bar"; in 4 + foo
 |                     ^

cannot coerce an integer to a string
1| let foo = 7; in "x${foo}"
 |                  ^
```

This commit changes the ExprConcatStrings expression vector to store a
sequence of expressions *and* their expansion locations so that error
locations can be reported accurately. For interpolation, the error is
reported at the beginning of the entire `${foo}`, not at the beginning
of `foo` because I thought this was slightly clearer. The previous
errors are now reported as:

```
cannot coerce an integer to a string
1| let foo = 7; in "bar" + foo
 |                         ^

cannot add a string to an integer
1| let foo = "bar"; in 4 + foo
 |                         ^

cannot coerce an integer to a string
1| let foo = 7; in "x${foo}"
 |                   ^
```

The error is reported at this kind of precise location even for
multi-line indented strings.

This probably helps with at least some of the cases mentioned in #561
2021-09-22 20:57:34 -06:00
Ben Burdette
c7e3d830c1 more debug stuff 2021-09-22 16:22:53 -06:00
Ben Burdette
cd8c232b55 add cout debugging 2021-09-15 16:16:53 -06:00
Ben Burdette
21071bfdeb shared_ptr for StaticEnv 2021-09-14 10:49:22 -06:00
Taeer Bar-Yam
1ffb9f1970 fix parse of /${foo}. was // + foo
I don't think this changes the way any program would behave, but it's a
cleaner internal representation.
2021-08-31 15:55:55 -04:00
Taeer Bar-Yam
8f9429dcab add antiquotations to paths 2021-08-06 06:46:05 -04:00
Maximilian Bosch
7c76964daa
libexpr: misc improvements for proper error position
When working on some more complex Nix code, there are sometimes rather
unhelpful or misleading error messages, especially if coerce-errors are
thrown.

This patch is a first steps towards improving that. I'm happy to file
more changes after that, but I'd like to gather some feedback first.

To summarize, this patch does the following things:

* Attrsets (a.k.a. `Bindings` in `libexpr`) now have a `Pos`. This is
  helpful e.g. to identify which attribute-set in `listToAttrs` is
  invalid.

* The `Value`-struct has a new method named `determinePos` which tries
  to guess the position of a value and falls back to a default if that's
  not possible.

  This can be used to provide better messages if a coercion fails.

* The new `determinePos`-API is used by `builtins.concatMap` now. With
  that change, Nix shows the exact position in the error where a wrong
  value was returned by the lambda.

  To make sure it's still obvious that `concatMap` is the problem,
  another stack-frame was added.

* The changes described above can be added to every other `primop`, but
  first I'd like to get some feedback about the overall approach.
2021-04-13 23:12:38 +02:00
Eelco Dolstra
8d4268d190 Improve error formatting
Changes:

* The divider lines are gone. These were in practice a bit confusing,
  in particular with --show-trace or --keep-going, since then there
  were multiple lines, suggesting a start/end which wasn't the case.

* Instead, multi-line error messages are now indented to align with
  the prefix (e.g. "error: ").

* The 'description' field is gone since we weren't really using it.

* 'hint' is renamed to 'msg' since it really wasn't a hint.

* The error is now printed *before* the location info.

* The 'name' field is no longer printed since most of the time it
  wasn't very useful since it was just the name of the exception (like
  EvalError). Ideally in the future this would be a unique, easily
  googleable error ID (like rustc).

* "trace:" is now just "…". This assumes error contexts start with
  something like "while doing X".

Example before:

  error: --- AssertionError ---------------------------------------------------------------------------------------- nix
  at: (7:7) in file: /home/eelco/Dev/nixpkgs/pkgs/applications/misc/hello/default.nix

       6|
       7|   x = assert false; 1;
        |       ^
       8|

  assertion 'false' failed
  ----------------------------------------------------- show-trace -----------------------------------------------------
  trace: while evaluating the attribute 'x' of the derivation 'hello-2.10'
  at: (192:11) in file: /home/eelco/Dev/nixpkgs/pkgs/stdenv/generic/make-derivation.nix

     191|         // (lib.optionalAttrs (!(attrs ? name) && attrs ? pname && attrs ? version)) {
     192|           name = "${attrs.pname}-${attrs.version}";
        |           ^
     193|         } // (lib.optionalAttrs (stdenv.hostPlatform != stdenv.buildPlatform && !dontAddHostSuffix && (attrs ? name || (attrs ? pname && attrs ? version)))) {

Example after:

  error: assertion 'false' failed

         at: (7:7) in file: /home/eelco/Dev/nixpkgs/pkgs/applications/misc/hello/default.nix

              6|
              7|   x = assert false; 1;
               |       ^
              8|

         … while evaluating the attribute 'x' of the derivation 'hello-2.10'

         at: (192:11) in file: /home/eelco/Dev/nixpkgs/pkgs/stdenv/generic/make-derivation.nix

            191|         // (lib.optionalAttrs (!(attrs ? name) && attrs ? pname && attrs ? version)) {
            192|           name = "${attrs.pname}-${attrs.version}";
               |           ^
            193|         } // (lib.optionalAttrs (stdenv.hostPlatform != stdenv.buildPlatform && !dontAddHostSuffix && (attrs ? name || (attrs ? pname && attrs ? version)))) {
2021-01-21 11:02:09 +01:00
Eelco Dolstra
75efa42134 Move <nix/fetchurl.nix> into the nix binary
This makes the statically linked nix binary just work, without needing
any additional files.
2020-12-22 14:43:20 +01:00
Eelco Dolstra
5999978a05 Make Headers an optional argument 2020-09-29 13:05:19 +02:00
Gregory Hale
faa5607f54 Merge remote-tracking branch 'origin/master' into github-api-token 2020-09-25 12:10:58 -04:00
Eelco Dolstra
236d9ee7f7 lstat() cleanup 2020-09-23 19:17:28 +02:00
Greg Hale
a303c0b6dc Fetch commits from github/gitlab using Auth header
`nix flake info` calls the github 'commits' API, which requires
authorization when the repository is private. Currently this request
fails with a 404.

This commit adds an authorization header when calling the 'commits' API.
It also changes the way that the 'tarball' API authenticates, moving the
user's token from a query parameter into the Authorization header.

The query parameter method is recently deprecated and will be disallowed
in November 2020. Using them today triggers a warning email.
2020-09-16 13:46:48 -04:00
Eelco Dolstra
54712aaf8a Merge remote-tracking branch 'origin/master' into flakes 2020-07-06 16:40:10 +02:00
Ben Burdette
5ae498872a assert for invalid fileorigin 2020-07-02 07:14:40 -06:00
Ben Burdette
1d43a6e123 use plain errPos instead of nixCode; fix tests 2020-06-23 15:30:13 -06:00
Ben Burdette
e6f93b94fc Merge branch 'master' into caveman-LOCs 2020-06-18 13:07:53 -06:00
Eelco Dolstra
1524752c17 Merge remote-tracking branch 'origin/master' into flakes 2020-06-17 10:26:52 +02:00
Eelco Dolstra
ccfa6b3eee Give better error message about <...> in pure eval mode 2020-06-15 16:12:27 +02:00
Eelco Dolstra
1fb762d11f Get rid of explicit ErrorInfo constructors 2020-06-15 14:06:58 +02:00
Eelco Dolstra
950b46821f Remove TreeInfo
The attributes previously stored in TreeInfo (narHash, revCount,
lastModified) are now stored in Input. This makes it less arbitrary
what attributes are stored where.

As a result, the lock file format has changed. An entry like

    "info": {
      "lastModified": 1585405475,
      "narHash": "sha256-bESW0n4KgPmZ0luxvwJ+UyATrC6iIltVCsGdLiphVeE="
    },
    "locked": {
      "owner": "NixOS",
      "repo": "nixpkgs",
      "rev": "b88ff468e9850410070d4e0ccd68c7011f15b2be",
      "type": "github"
    },

is now stored as

    "locked": {
      "owner": "NixOS",
      "repo": "nixpkgs",
      "rev": "b88ff468e9850410070d4e0ccd68c7011f15b2be",
      "type": "github",
      "lastModified": 1585405475,
      "narHash": "sha256-bESW0n4KgPmZ0luxvwJ+UyATrC6iIltVCsGdLiphVeE="
    },

The 'Input' class is now a dumb set of attributes. All the fetcher
implementations subclass InputScheme, not Input. This simplifies the
API.

Also, fix substitution of flake inputs. This was broken since lazy
flake fetching started using fetchTree internally.
2020-05-30 00:44:11 +02:00
Ben Burdette
b7057fa627 remove error-demo from make; clean up comment 2020-05-21 16:04:18 -06:00
Ben Burdette
6a420d672c print LOC for stdin, string args 2020-05-20 22:18:26 -06:00
Ben Burdette
ef9dd9f9bc formatting and a few minor changes 2020-05-13 15:56:39 -06:00
Ben Burdette
72ecccee57 convert to logWarning format 2020-05-12 12:19:34 -06:00
Ben Burdette
7c3138844c more pos reporting 2020-05-11 17:34:57 -06:00
Ben Burdette
631642c5b4 new format for pos 2020-05-11 16:58:08 -06:00
Ben Burdette
59b1f5c701 Merge branch 'master' into errors-phase-2 2020-05-11 14:35:30 -06:00
Ben Burdette
55eb717148 add pos to errorinfo, remove from hints 2020-05-08 18:18:28 -06:00
Ben Burdette
ab6f0b9641 convert some printError calls to logError 2020-05-03 08:01:25 -06:00
Ben Burdette
e4fb9a3849 remove 'format' from Error constructor calls 2020-04-21 17:07:07 -06:00
Domen Kožar
a693a9fa4b
Attach pos to if expression errors 2020-04-09 09:45:15 +02:00
Nikola Knezevic
7867685dcd after flake rebase 2020-04-08 22:26:57 +02:00
Nikola Knezevic
f5095594e7 datatransfer.{cc,hh} -> filetransfer.{cc,hh} 2020-04-08 22:26:57 +02:00
Nikola Knezevic
c4c1ae0a00 DownloadError -> DataTransferError 2020-04-08 22:26:57 +02:00
Nikola Knezevic
741e9012d3 Rename src/lib/download.* to src/lib/datatransfer.* 2020-04-08 22:26:57 +02:00
Eelco Dolstra
9ed097db7b
Merge pull request #3468 from Infinisil/functionArgsPositions
Make function arguments retain position info
2020-04-08 15:29:39 +02:00
Eelco Dolstra
462421d345 Backport libfetchers from the flakes branch
This provides a pluggable mechanism for defining new fetchers. It adds
a builtin function 'fetchTree' that generalizes existing fetchers like
'fetchGit', 'fetchMercurial' and 'fetchTarball'. 'fetchTree' takes a
set of attributes, e.g.

  fetchTree {
    type = "git";
    url = "https://example.org/repo.git";
    ref = "some-branch";
    rev = "abcdef...";
  }

The existing fetchers are just wrappers around this. Note that the
input attributes to fetchTree are the same as flake input
specifications and flake lock file entries.

All fetchers share a common cache stored in
~/.cache/nix/fetcher-cache-v1.sqlite. This replaces the ad hoc caching
mechanisms in fetchGit and download.cc (e.g. ~/.cache/nix/{tarballs,git-revs*}).

This also adds support for Git worktrees (c169ea5904).
2020-04-07 09:03:14 +02:00
Silvan Mosberger
c34e96f7e0
Make function arguments retain position info
This allows querying the location of function arguments. E.g.

  builtins.unsafeGetAttrPos "x" (builtins.functionArgs ({ x }: null))

  => { column = 57; file = "/home/infinisil/src/nix/inst/test.nix"; line = 1; }
2020-04-02 05:52:52 +02:00
Eelco Dolstra
e02481ded2 parseExprFromString(): Use std::string_view 2020-03-11 16:56:29 +01:00
Eelco Dolstra
acb71aa5c6 Tweak error message 2019-12-15 10:44:53 +01:00
Dima
d89d9958a7 bugfix: Adding depth limit to resolveExprPath
There is no termination condition for evaluation of cyclical
expression paths which can lead to infinite loops. This addresses
one spot in the parser in a similar fashion as utils.cc/canonPath
does.

This issue can be reproduced by something like:

```
ln -s a b
ln -s b a

nix-instantiate -E 'import ./a'
```
2019-12-13 14:51:30 +01:00
Eelco Dolstra
1ec6e6e11e
Add feature to disable URL literals
E.g.

  $ nix-build '<nixpkgs>' -A hello --experimental-features no-url-literals
  error: URL literals are disabled, at /nix/store/vsjamkzh15r3c779q2711az826hqgvzr-nixpkgs-20.03pre194957.bef773ed53f/nixpkgs/pkgs/top-level/all-packages.nix:1236:11

Helps with implementing https://github.com/NixOS/rfcs/pull/45.
2019-11-26 19:48:34 +01:00
Eelco Dolstra
926d3e5bb0
Fix Bison 2.4 warning 2019-10-09 22:57:37 +02:00
Eelco Dolstra
99b73fb507
OCD performance fix: {find,count}+insert => insert 2019-10-09 16:06:29 +02:00
Eelco Dolstra
f8b30338ac
Refactor downloadCached() interface
(cherry picked from commit df3f5a78d5)
2019-06-24 22:12:26 +02:00
Eelco Dolstra
dc29e9fb47
downloadCached: Return ETag
(cherry picked from commit 529add316c)
2019-06-24 21:58:33 +02:00
Eelco Dolstra
22f2744afd
Iterate over references 2019-05-28 23:05:08 +02:00
Eelco Dolstra
9eaebbf575
Merge branch 'attrPaths' of https://github.com/NinjaTrappeur/nix 2019-05-28 22:59:05 +02:00
Eelco Dolstra
f32fbf952d Fix Bison 3.3 warning 2019-03-27 21:09:31 +01:00
volth
deaa6e9a34
parser.y: right-associativity of -> 2018-07-23 07:28:48 +00:00
volth
85fe4a819c
parser.y: fix assoc of -> and < > <= >=
The parser allowed senseless `a > b > c` but disallowed `a -> b -> c` which seems valid
It might be a typo
2018-07-21 15:24:51 +00:00
Eelco Dolstra
f3c85f9eb3
Revert "Throw a specific error for incomplete parse errors."
This reverts commit 6498adb002. We don't
actually use IncompleteParseError in 'nix repl'.
2018-05-11 11:40:50 +02:00
Eelco Dolstra
53ec5ac69f
Fix some random -Wconversion warnings 2018-05-02 13:56:34 +02:00
Félix Baylac-Jacqué
00584bb091
parser: Allow mixed nested and top-level attrpaths
Fixes #2077.
2018-04-18 18:44:38 +02:00
Eelco Dolstra
6cf7c6a6b0
Remove git:// support in NIX_PATH
This didn't support specifying a revision/branch, and was restricted
to git:// URIs (since https:// or ssh:// would be ambiguous).
2017-11-03 13:55:31 +01:00
Eelco Dolstra
72cd52c3cd
builtins.fetchgit: Support importing a working tree
For example, you can write

  src = fetchgit ./.;

and if ./. refers to an unclean working tree, that tree will be copied
to the Nix store. This removes the need for "cleanSource".
2017-10-30 19:59:25 +01:00
Eelco Dolstra
e38382895d
builtins.fetchGit: Return an attrset with revision info
This adds rev, shortRev and revCount attributes, equal to what Hydra
provides. E.g.

  $ nix eval '(fetchGit https://github.com/NixOS/patchelf.git)'
  { outPath = "/nix/store/ghigrkw02l440g8vfxa9wj4c3zpfmw99-source"; rev = "29c085fd9d3fc972f75b3961905d6b4ecce7eb2b"; revCount = 303; shortRev = "29c085f"; }
2017-10-30 11:49:03 +01:00
Jörg Thalheim
2fd8f8bb99 Replace Unicode quotes in user-facing strings by ASCII
Relevant RFC: NixOS/rfcs#4

$ ag -l | xargs sed -i -e "/\"/s/’/'/g;/\"/s/‘/'/g"
2017-07-30 12:32:45 +01:00
Eelco Dolstra
4c9ff89c26
nix-build/nix-shell: Eliminate call to nix-instantiate / nix-store
Note that this removes the need for a derivation symlink, so the
--drv-path and --add-drv-link flags now do nothing.
2017-07-26 17:29:09 +02:00
Eelco Dolstra
465cb68244
Figure out the user's home directory if $HOME is not set 2017-05-05 17:08:23 +02:00
Eelco Dolstra
215b70f51e
Revert "Get rid of unicode quotes (#1140)"
This reverts commit f78126bfd6. There
really is no need for such a massive change...
2016-11-26 00:38:01 +01:00
Guillaume Maudoux
f78126bfd6 Get rid of unicode quotes (#1140) 2016-11-25 15:48:27 +01:00
Eelco Dolstra
c55bf085eb printMsg(lvlError, ...) -> printError(...) etc. 2016-09-21 16:54:53 +02:00
Eelco Dolstra
90ad02bf62 Enable HTTP/2 support
The binary cache store can now use HTTP/2 to do lookups. This is much
more efficient than HTTP/1.1 due to multiplexing: we can issue many
requests in parallel over a single TCP connection. Thus it's no longer
necessary to use a bunch of concurrent TCP connections (25 by
default).

For example, downloading 802 .narinfo files from
https://cache.nixos.org/, using a single TCP connection, takes 11.8s
with HTTP/1.1, but only 0.61s with HTTP/2.

This did require a fairly substantial rewrite of the Downloader class
to use the curl multi interface, because otherwise curl wouldn't be
able to do multiplexing for us. As a bonus, we get connection reuse
even with HTTP/1.1. All downloads are now handled by a single worker
thread. Clients call Downloader::enqueueDownload() to tell the worker
thread to start the download, getting a std::future to the result.
2016-09-14 16:36:02 +02:00
Eelco Dolstra
d8bf0d4859 Support Git repos in the Nix path
E.g.

  $ nix-build -I nixpkgs=git://github.com/NixOS/nixpkgs '<nixpkgs>' -A hello

This is not extremely useful yet because you can't specify a
branch/revision.
2016-04-29 21:07:47 +02:00
Eelco Dolstra
363f37d084 Make the search path lazier with non-fatal errors
Thus, -I / $NIX_PATH entries are now downloaded only when they are
needed for evaluation. An error to download an entry is a non-fatal
warning (just like non-existant paths).

This does change the semantics of builtins.nixPath, which now returns
the original, rather than resulting path. E.g., before we had

  [ { path = "/nix/store/hgm3yxf1lrrwa3z14zpqaj5p9vs0qklk-nixexprs.tar.xz"; prefix = "nixpkgs"; } ... ]

but now

  [ { path = "https://nixos.org/channels/nixos-16.03/nixexprs.tar.xz"; prefix = "nixpkgs"; } ... ]

Fixes #792.
2016-04-14 15:32:24 +02:00
Eelco Dolstra
e9c50064b5 Add an HTTP binary cache store
Allowing stuff like

  NIX_REMOTE=https://cache.nixos.org nix-store -qR /nix/store/x1p1gl3a4kkz5ci0nfbayjqlqmczp1kq-geeqie-1.1

or

  NIX_REMOTE=https://cache.nixos.org nix-store --export /nix/store/x1p1gl3a4kkz5ci0nfbayjqlqmczp1kq-geeqie-1.1 | nix-store --import
2016-02-29 18:15:20 +01:00
Scott Olson
6498adb002 Throw a specific error for incomplete parse errors.
`nix-repl` will use this for deciding whether to keep waiting for input or
error out right away.
2016-02-24 04:32:21 -06:00
Eelco Dolstra
b3e8d72770 Merge pull request #762 from ctheune/ctheune-floats
Implement floats
2016-02-12 12:49:59 +01:00
Eelco Dolstra
c10c61449f Eliminate the "store" global variable
Also, move a few free-standing functions into StoreAPI and Derivation.

Also, introduce a non-nullable smart pointer, ref<T>, which is just a
wrapper around std::shared_ptr ensuring that the pointer is never
null. (For reference-counted values, this is better than passing a
"T&", because the latter doesn't maintain the refcount. Usually, the
caller will have a shared_ptr keeping the value alive, but that's not
always the case, e.g., when passing a reference to a std::thread via
std::bind.)
2016-02-04 14:28:26 +01:00
Christian Theune
14ebde5289 First hit at providing support for floats in the language. 2016-01-05 00:40:40 +01:00
Eelco Dolstra
6bd2c7bb38 OCD: foreach -> C++11 ranged for 2015-07-17 20:13:56 +02:00
Guillaume Maudoux
65e4dcd69b Fix the hack that resets the scanner state. 2015-07-03 13:53:36 +02:00
Eelco Dolstra
6519f06f39 nix-env/nix-instantiate/nix-build: Support URIs
For instance, you can install Firefox from a specific Nixpkgs revision
like this:

  $ nix-env -f 63def04891.tar.gz -iA firefox

Or build a package from the latest nixpkgs-unstable channel:

  $ nix-build https://nixos.org/channels/nixpkgs-unstable/nixexprs.tar.xz -A hello
2015-05-06 14:54:31 +02:00
Eelco Dolstra
9451ef3731 Allow URLs in the Nix search path
E.g. to install "hello" from the latest Nixpkgs:

  $ nix-build '<nixpkgs>' -A hello -I nixpkgs=https://nixos.org/channels/nixpkgs-unstable/nixexprs.tar.xz

Or to install a specific version of NixOS:

  $ nixos-rebuild switch -I nixpkgs=63def04891.tar.gz
2015-05-05 17:09:42 +02:00
Eelco Dolstra
15d2d3c34e Add restricted evaluation mode
If ‘--option restrict-eval true’ is given, the evaluator will throw an
exception if an attempt is made to access any file outside of the Nix
search path. This is primarily intended for Hydra, where we don't want
people doing ‘builtins.readFile ~/.ssh/id_dsa’ or stuff like that.
2015-02-23 15:54:31 +01:00
Eelco Dolstra
c33244d7c1 Merge branch 'tilde-paths' of https://github.com/shlevy/nix 2015-02-19 14:55:06 +01:00
Shea Levy
c4653afbcd tilde paths: The rest of the string has to start with a slash anyway 2015-02-19 08:52:13 -05:00
Shea Levy
e3e38a048e tilde paths: construct the entire path at parse time 2015-02-19 08:51:21 -05:00
Shea Levy
4b7c9f834c tilde paths: get HOME at parse time 2015-02-19 08:49:10 -05:00
Eelco Dolstra
9bedd9b09b Remove obsolete reference to ~ operator 2015-02-19 14:41:22 +01:00
Shea Levy
e0953d53de Allow the leading component of a path to be a ~ 2015-02-19 08:05:16 -05:00
Eelco Dolstra
153a943de7 Show position info for failing <...> lookups 2015-01-07 13:43:55 +01:00
Eelco Dolstra
4e0607369e Pedantry 2014-12-14 01:51:14 +01:00
Eelco Dolstra
b6809608cc Get rid of some unnecessary ExprConcatStrings nodes in dynamic attrs
This gives a ~18% speedup in NixOS evaluation (after converting
most calls to hasAttr/getAttr to dynamic attrs).
2014-10-05 01:04:58 +02:00
Eelco Dolstra
11849a320e Use proper quotes everywhere 2014-08-20 18:03:48 +02:00
Eelco Dolstra
3d221a7bb1 Rename nixPath to __nixPath
The name ‘nixPath’ breaks existing code.
2014-07-30 11:28:39 +02:00
Eelco Dolstra
d8c061e044 Remove ExprBuiltin
It's slower than ExprVar since it doesn't compute a static
displacement. Since we're not using the throw primop in the
implementation of <...> anymore, it's also not really needed.
2014-05-26 17:14:28 +02:00
Eelco Dolstra
62a6eeb1f3 Make the Nix search path declarative
Nix search path lookups like <nixpkgs> are now desugared to ‘findFile
nixPath <nixpkgs>’, where ‘findFile’ is a new primop. Thus you can
override the search path simply by saying

  let
    nixPath = [ { prefix = "nixpkgs"; path = "/my-nixpkgs"; } ];
  in ... <nixpkgs> ...

In conjunction with ‘scopedImport’ (commit
c273c15cb1), the Nix search path can be
propagated across imports, e.g.

  let

    overrides = {
      nixPath = [ ... ] ++ builtins.nixPath;
      import = fn: scopedImport overrides fn;
      scopedImport = attrs: fn: scopedImport (overrides // attrs) fn;
      builtins = builtins // overrides;
    };

  in scopedImport overrides ./nixos
2014-05-26 17:02:22 +02:00
Eelco Dolstra
39d72640c2 Ensure that -I flags get included in nixPath
Also fixes #261.
2014-05-26 16:52:31 +02:00
Eelco Dolstra
c273c15cb1 Add primop ‘scopedImport’
‘scopedImport’ works like ‘import’, except that it takes a set of
attributes to be added to the lexical scope of the expression,
essentially extending or overriding the builtin variables.  For
instance, the expression

  scopedImport { x = 1; } ./foo.nix

where foo.nix contains ‘x’, will evaluate to 1.

This has a few applications:

* It allows getting rid of function argument specifications in package
  expressions. For instance, a package expression like:

    { stdenv, fetchurl, libfoo }:

    stdenv.mkDerivation { ... buildInputs = [ libfoo ]; }

  can now we written as just

    stdenv.mkDerivation { ... buildInputs = [ libfoo ]; }

  and imported in all-packages.nix as:

    bar = scopedImport pkgs ./bar.nix;

  So whereas we once had dependencies listed in three places
  (buildInputs, the function, and the call site), they now only need
  to appear in one place.

* It allows overriding builtin functions. For instance, to trace all
  calls to ‘map’:

  let
    overrides = {
      map = f: xs: builtins.trace "map called!" (map f xs);

      # Ensure that our override gets propagated by calls to
      # import/scopedImport.
      import = fn: scopedImport overrides fn;

      scopedImport = attrs: fn: scopedImport (overrides // attrs) fn;

      # Also update ‘builtins’.
      builtins = builtins // overrides;
    };
  in scopedImport overrides ./bla.nix

* Similarly, it allows extending the set of builtin functions. For
  instance, during Nixpkgs/NixOS evaluation, the Nixpkgs library
  functions could be added to the default scope.

There is a downside: calls to scopedImport are not memoized, unlike
import. So importing a file multiple times leads to multiple parsings
/ evaluations. It would be possible to construct the AST only once,
but that would require careful handling of variables/environments.
2014-05-26 14:26:29 +02:00