Commit graph

159 commits

Author SHA1 Message Date
Tuomas Tynkkynen a0e38c16bc libexpr: Recognize newline in more places in lexer
Flex's regexes have an annoying feature: the dot matches everything
except a newline. This causes problems for expressions like:

"${0}\
"

where the backslash-newline combination matches this rule instead of the
intended one mentioned in the comment:

    <STRING>\$|\\|\$\\ {
                    /* This can only occur when we reach EOF, otherwise the above
                    (...|\$[^\{\"\\]|\\.|\$\\.)+ would have triggered.
                    This is technically invalid, but we leave the problem to the
                    parser who fails with exact location. */
                    return STR;
                }
However, the parser actually accepts the resulting token sequence
('"' DOLLAR_CURLY 0 '}' STR '"'), which is a problem because the lexer
rule didn't assign anything to yylval. Ultimately this leads to a crash
when dereferencing a NULL pointer in ExprConcatStrings::bindVars().

The fix does change the syntax of the language in some corner cases
but I think it's only turning previously invalid (or crashing) syntax
to valid syntax. E.g.

"a\
b"

and

''a''\
b''

were previously syntax errors but now both result in "a\nb".

Found by afl-fuzz.
2018-03-02 17:30:48 +02:00
Tuomas Tynkkynen 77e9e1ed91 libexpr: Fix prim_replaceStrings() to work on an empty source string
Otherwise, running e.g.

nix-instantiate --eval -E --strict 'builtins.replaceStrings [""] ["X"] "abc"'

would just hang in an infinite loop.

Found by afl-fuzz.

First attempt of this was reverted in e2d71bd186 because it caused
another infinite loop, which is fixed now and a test added.
2018-02-26 19:49:13 +02:00
Eelco Dolstra e2d71bd186
Revert "libexpr: Fix prim_replaceStrings() to work on an empty source string"
This reverts commit 4ea9707591.

It causes an infinite loop in Nixpkgs evaluation,
e.g. "nix-instantiate -A hello" hung.

PR #1886.
2018-02-21 15:35:28 +01:00
Tuomas Tynkkynen 4ea9707591 libexpr: Fix prim_replaceStrings() to work on an empty source string
Otherwise, running e.g.

nix-instantiate --eval -E --strict 'builtins.replaceStrings [""] ["X"] "abc"'

would just hang in an infinite loop.

Found by afl-fuzz.
2018-02-19 23:20:26 +02:00
Shea Levy b095c06139
Add splitVersion primop.
Fixes #1868.
2018-02-14 09:55:43 -05:00
Shea Levy 48c192ca2d
builtins.path test: Don't rely on shlevy's XDG_RUNTIME_DIR 2018-02-07 10:26:53 -05:00
Shea Levy 69d82e5c58
Add path primop.
builtins.path allows specifying the name of a path (which makes paths
with store-illegal names now addable), allows adding paths with flat
instead of recursive hashes, allows specifying a filter (so is a
generalization of filterSource), and allows specifying an expected
hash (enabling safe path adding in pure mode).
2018-02-06 16:48:08 -05:00
Eelco Dolstra 2c39e4eca0
Revert "Don't parse "x:x" as a URI"
This reverts commit f90f660b24.

This broke Hydra's release.nix, which contained

  preCheck = ''export LOGNAME=${LOGNAME:-foo}'';
2017-11-14 15:10:52 +01:00
Eelco Dolstra f90f660b24
Don't parse "x:x" as a URI
URIs now have to contain "://" or start with "channel:".
2017-10-30 17:58:01 +01:00
Nicolas B. Pierron b8867a0239 Add builtins.string function.
The function 'builtins.split' takes a POSIX extended regular expression
and an arbitrary string. It returns a list of non-matching substring
interleaved by lists of matched groups of the regular expression.

```nix
with builtins;
assert split "(a)b" "abc"      == [ "" [ "a" ] "c" ];
assert split "([ac])" "abc"    == [ "" [ "a" ] "b" [ "c" ] "" ];
assert split "(a)|(c)" "abc"   == [ "" [ "a" null ] "b" [ null "c" ] "" ];
assert split "([[:upper:]]+)" "  FOO   "
                               == [ "  " [ "FOO" ] "   " ];
```
2017-08-15 20:04:11 +00:00
Graham Christensen 364f75e03a Update mailing list. 2017-07-18 08:04:01 -04:00
Eelco Dolstra f134fc4cbe
Document that builtins.match takes a POSIX extended RE 2017-05-17 12:18:18 +02:00
Guillaume Maudoux a474425425 Fix lexer to support $' in multiline strings. 2017-05-01 01:15:40 +02:00
Guillaume Maudoux e4b82af387 Improve error message on trailing path slashes 2016-11-27 17:48:46 +01:00
Guillaume Maudoux a5e761dddb Fix comments parsing
Fixed the parsing of multiline strings ending with an even number of
stars, like /** this **/.
Added test cases for comments.
2016-11-13 17:20:34 +01:00
Eelco Dolstra 26d92017d3 Add builtin function "partition"
The implementation of "partition" in Nixpkgs is O(n^2) (because of the
use of ++), and for some reason was causing stack overflows in
multi-threaded evaluation (not sure why).

This reduces "nix-env -qa --drv-path" runtime by 0.197s and memory
usage by 298 MiB (in non-Boehm mode).
2016-08-29 19:36:54 +02:00
Eelco Dolstra e03d6e0998 Fix broken number parsing in fromJSON
The call to tmp_number.append had its arguments mixed up. Also, JSON
does not allow a trailing "," after array/object members.
2016-02-15 15:01:26 +01:00
Eelco Dolstra eb62e23f14 Fix test broken by #762 2016-02-15 15:01:26 +01:00
Eelco Dolstra b3e8d72770 Merge pull request #762 from ctheune/ctheune-floats
Implement floats
2016-02-12 12:49:59 +01:00
Eelco Dolstra 4f7824c58e Remove tests/lexer.sh
"tests/lang.sh" can handle this.
2016-02-01 18:27:37 +01:00
Christian Theune 5cdcaf5e8e Adapt tests to show that floats work properly. 2016-01-06 10:03:24 +01:00
Eelco Dolstra 6f1743b1a5 Support SHA-512 hashes
Fixes #679.

Note: on x86_64, SHA-512 is considerably faster than SHA-256 (198 MB/s
versus 131 MB/s).
2015-11-04 16:37:49 +01:00
Eelco Dolstra 76cc8e97a2 Add sort primop 2015-07-28 18:39:39 +02:00
Eelco Dolstra 50807f3dd5 Add primop genList
This can be used to implement functions like ‘imap’ (or for that
matter, ‘map’) without the quadratic complexity incurred by calling
‘++’ repeatedly.
2015-07-28 17:28:35 +02:00
Eelco Dolstra d6d5885c15 Add replaceStrings primop
This is a generalisation of replaceChars in Nixpkgs.
2015-07-24 15:32:24 +02:00
Eelco Dolstra 2e8fd4c5cd Add concatStringsSep as a primop
This fixes the quadratic behaviour of concatStrings/concatStringsSep
in Nixpkgs.
2015-07-24 02:38:09 +02:00
Eelco Dolstra 14be783676 Add primops all and any
These are used thousands of times during NixOS evaluation, so it's
useful to speed them up.
2015-07-23 19:23:11 +02:00
Eelco Dolstra 61af14a921 Add foldl' primop 2015-07-23 17:03:02 +02:00
Guillaume Maudoux 467977f203 Fix the parsing of "$"'s in strings. 2015-07-03 14:09:58 +02:00
Shea Levy 73bf32ce94 Merge remote-tracking branch 'shlevy/baseNameOf-no-copy'
baseNameOf: Don't copy paths to the store first
2015-01-29 03:29:09 -05:00
Eelco Dolstra 976df480c9 Add a primop for regular expression pattern matching
The function ‘builtins.match’ takes a POSIX extended regular
expression and an arbitrary string. It returns ‘null’ if the string
does not match the regular expression. Otherwise, it returns a list
containing substring matches corresponding to parenthesis groups in
the regex. The regex must match the entire string (i.e. there is an
implied "^<pat>$" around the regex).  For example:

  match "foo" "foobar" => null
  match "foo" "foo" => []
  match "f(o+)(.*)" "foooobar" => ["oooo" "bar"]
  match "(.*/)?([^/]*)" "/dir/file.nix" => ["/dir/" "file.nix"]
  match "(.*/)?([^/]*)" "file.nix" => [null "file.nix"]

The following example finds all regular files with extension .nix or
.patch underneath the current directory:

  let

    findFiles = pat: dir: concatLists (mapAttrsToList (name: type:
      if type == "directory" then
        findFiles pat (dir + "/" + name)
      else if type == "regular" && match pat name != null then
        [(dir + "/" + name)]
      else []) (readDir dir));

  in findFiles ".*\\.(nix|patch)" (toString ./.)
2014-11-25 11:47:06 +01:00
Shea Levy 997defa166 Add functors (callable attribute sets).
With this, attribute sets with a `__functor` attribute can be applied
just like normal functions. This can be used to attach arbitrary
metadata to a function without callers needing to treat it specially.
2014-11-15 16:12:05 -05:00
Shea Levy c9bd6a1de4 Fix context test 2014-10-18 20:34:48 -04:00
Eelco Dolstra c3f0a489f9 Add primop ‘catAttrs’ 2014-10-04 18:15:03 +02:00
Eelco Dolstra d4fcbe1687 Add primop ‘attrValues’ 2014-10-04 16:41:24 +02:00
Shea Levy 3fd2d2187e Add test for readDir primop 2014-10-03 22:32:11 +02:00
Eelco Dolstra 0cd6596b0e Add ‘deepSeq’ primop
Note that unlike ‘lib.deepSeq’ in Nixpkgs, this handles cycles.
2014-09-22 16:05:00 +02:00
Eelco Dolstra a54c263402 Add ‘seq’ primop 2014-09-22 16:05:00 +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 beaf3e90af Add builtin function ‘fromJSON’
Fixes #294.
2014-07-04 13:34:15 +02:00
Eelco Dolstra ee7fe64c0a == operator: Ignore string context
There really is no case I can think of where taking the context into
account is useful. Mostly it's just very inconvenient.
2014-06-10 14:02:56 +02:00
Eelco Dolstra ceed819284 Fix test 2014-05-29 19:04:27 +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 a8edf185a9 Add constant ‘nixPath’
It contains the Nix expression search path as a list of { prefix, path
} sets, e.g.

  [ { path = "/nix/var/nix/profiles/per-user/root/channels/nixos"; prefix = ""; }
    { path = "/etc/nixos/configuration.nix"; prefix = "nixos-config"; }
    { path = "/home/eelco/Dev/nix/inst/share/nix/corepkgs"; prefix = "nix"; }
  ]
2014-05-26 14:55:47 +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
Shea Levy 908e9ce259 If a dynamic attribute name evaluates to null, remove it from the set 2014-03-10 10:14:50 +01:00
Eelco Dolstra 5ad263c26b Test some more primops 2014-02-26 19:08:44 +01:00
Shea Levy f9913f4422 Allow "bare" dynamic attrs
Now, in addition to a."${b}".c, you can write a.${b}.c (applicable
wherever dynamic attributes are valid).

Signed-off-by: Shea Levy <shea@shealevy.com>
2014-01-14 14:00:15 +01:00
Eelco Dolstra 7a61c88dbb Merge branch 'dynamic-attrs-no-sugar' of github.com:shlevy/nix 2014-01-06 15:46:18 +01:00