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2489 commits

Author SHA1 Message Date
Sergei Trofimovich
b74962c92b src/libexpr/search-path.cc: avoid out-of-bounds read on string_view
Without the change build with `-D_GLIBCXX_ASSERTIONS` exposes testsuite
assertion:

    $ gdb src/libexpr/tests/libnixexpr-tests
    Reading symbols from src/libexpr/tests/libnixexpr-tests...
    (gdb) break __glibcxx_assert_fail
    (gdb) run
    (gdb) bt
    in std::__glibcxx_assert_fail(char const*, int, char const*, char const*)@plt () from /mnt/archive/big/git/nix/src/libexpr/libnixexpr.so
    in std::basic_string_view<char, std::char_traits<char> >::operator[] (this=0x7fffffff56c0, __pos=4)
        at /nix/store/r74fw2j8rx5idb0w8s1s6ynwwgs0qmh9-gcc-14.0.0/include/c++/14.0.0/string_view:258
    in nix::SearchPath::Prefix::suffixIfPotentialMatch (this=0x7fffffff5780, path=...) at src/libexpr/search-path.cc:15
    in nix::SearchPathElem_suffixIfPotentialMatch_partialPrefix_Test::TestBody (this=0x555555a17540) at src/libexpr/tests/search-path.cc:62

As string sizes are usigned types `(a - b) > 0` effectively means
`a != b`. While the intention should be `a > b`.

The change fixes test suite pass.
2023-08-14 22:07:37 +01:00
John Ericson
44c8d83831 Create outputOf primop.
In the Nix language, given a drv path, we should be able to construct
another string referencing to one of its output. We can do this today
with `(import drvPath).output`, but this only works for derivations we
already have.

With dynamic derivations, however, that doesn't work well because the
`drvPath` isn't yet built: importing it like would need to trigger IFD,
when the whole point of this feature is to do "dynamic build graph"
without IFD!

Instead, what we want to do is create a placeholder value with the right
string context to refer to the output of the as-yet unbuilt derivation.
A new primop in the language, analogous to `builtins.placeholder` can be
used to create one. This will achieve all the right properties. The
placeholder machinery also will match out the `outPath` attribute for CA
derivations works.

In 60b7121d2c we added that type of
placeholder, and the derived path and string holder changes necessary to
support it. Then in the previous commit we cleaned up the code
(inspiration finally hit me!) to deduplicate the code and expose exactly
what we need. Now, we can wire up the primop trivally!

Part of RFC 92: dynamic derivations (tracking issue #6316)

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2023-08-14 09:37:37 -04:00
John Ericson
e7c39ff00b Rework evaluator SingleDerivedPath infra
`EvalState::mkSingleDerivedPathString` previously contained its own
inverse (printing, rather than parsing) in order to validate what was
parsed. Now that is pulled out into its own separate function:
`EvalState::coerceToSingleDerivedPath`.

In additional that pulled out logic is deduplicated with
`EvalState::mkOutputString` via `EvalState::mkOutputStringRaw`, which is
itself deduplicated (and generalized) with
`DownstreamPlaceholder::mkOutputStringRaw`.

All these changes make the unit tests simpler.

(We would ideally write more unit tests for `mkSingleDerivedPathString`
`coerceToSingleDerivedPath` directly, but we cannot yet do that because
the IO in reading the store path won't work when the dummy store cannot
hold anything. Someday we'll have a proper in-memory store which will
work for this.)

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2023-08-14 08:44:50 -04:00
John Ericson
a04720e68c Rename optOutputPath to optStaticOutputPath
This choice of variable name makes it more clear what is going on.

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2023-08-14 08:44:48 -04:00
Robert Hensing
584ff408a4
Merge pull request #8735 from obsidiansystems/defexpr
Factor out `nix-defexpr` path computation
2023-08-11 20:32:03 +02:00
John Ericson
60b7121d2c Make the Derived Path family of types inductive for dynamic derivations
We want to be able to write down `foo.drv^bar.drv^baz`:
`foo.drv^bar.drv` is the dynamic derivation (since it is itself a
derivation output, `bar.drv` from `foo.drv`).

To that end, we create `Single{Derivation,BuiltPath}` types, that are
very similar except instead of having multiple outputs (in a set or
map), they have a single one. This is for everything to the left of the
rightmost `^`.

`NixStringContextElem` has an analogous change, and now can reuse
`SingleDerivedPath` at the top level. In fact, if we ever get rid of
`DrvDeep`, `NixStringContextElem` could be replaced with
`SingleDerivedPath` entirely!

Important note: some JSON formats have changed.

We already can *produce* dynamic derivations, but we can't refer to them
directly. Today, we can merely express building or example at the top
imperatively over time by building `foo.drv^bar.drv`, and then with a
second nix invocation doing `<result-from-first>^baz`, but this is not
declarative. The ethos of Nix of being able to write down the full plan
everything you want to do, and then execute than plan with a single
command, and for that we need the new inductive form of these types.

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
2023-08-10 00:08:32 -04:00
Eelco Dolstra
eb1302670e
Merge pull request #8769 from edolstra/generalize-tarball-urls
Don't require .tar/.zip extension for tarball flakerefs
2023-08-07 17:02:17 +02:00
Théophane Hufschmitt
5df0f1755f
Merge pull request #8692 from obsidiansystems/add-another-xp-check
Feature gate `DownstreamPlaceholder::unknownCaOutput`
2023-08-07 13:11:44 +02:00
John Ericson
9b908fa70a Factor out nix-defexpr path computation
Avoid duplicated code, and also avoid "on the fly" path construction
(which makes it harder to keep track of which paths we use).

The factored out code doesn't create the Nix state dir anymore, but this
is fine because other in nix-env and nix-channel does:

- nix-channel: Line 158 in this commit

- nix-env: Line 1407 in this commit
2023-08-02 12:54:48 -04:00
Eelco Dolstra
d00469ebf9
Merge pull request #8762 from obsidiansystems/split-out-eval-settings
Move evaluator settings (type and global) to separate file/header
2023-08-02 16:54:02 +02:00
Eelco Dolstra
d9e7758f47 Don't require .tar/.zip extension for tarball flakerefs
Special-casing the file name is rather ugly, so we shouldn't do
that. So now any {file,http,https} URL is handled by
TarballInputScheme, except for non-flake inputs (i.e. inputs that have
the attribute `flake = false`).
2023-08-01 16:07:20 +02:00
John Ericson
1570e80219 Move evaluator settings (type and global) to separate file/header 2023-07-31 10:14:15 -04:00
Robert Hensing
33d58a90c2 toJSON: Add attribute path to trace 2023-07-31 13:02:54 +02:00
Alex Ameen
2d1d81114d
Add parseFlakeRef and flakeRefToString builtins (#8670)
Over the last year or so I've run into several use cases where I need to
parse and/or serialize URLs for use by `builtins.fetchTree` or
`builtins.getFlake`, largely in order to produce _lockfile-like_ files
for lang2nix frameworks or tools which use `nix` internally to drive
builds.

I've gone through the painstaking process of emulating
`nix::FlakeRef::fromAttrs` and `nix::parseFlakeRef` several times with
mixed success; but these are difficult to create and even harder to
maintain if I hope to stay aligned with changes to the real
parser/serializer.

I understand why adding new `builtins` isn't something we want to do
flagrantly. I'm recommending this addition simply because I keep
encountering use cases where I need to parse/serialize these URIs in
`nix` expressions, and I want a reliable solution.

Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Co-authored-by: John Ericson <git@JohnEricson.me>
2023-07-25 17:43:33 +00:00
John Ericson
4685c9b55f
Merge pull request #8664 from ncfavier/merge-dynamic-attrs
parser: merge nested dynamic attributes
2023-07-23 11:03:38 -04:00
Naïm Favier
570a1a3ad7
parser: merge nested dynamic attributes
Fixes https://github.com/NixOS/nix/issues/7115
2023-07-21 17:14:03 +02:00
Eelco Dolstra
7ac24d9525
Merge pull request #8650 from obsidiansystems/content-address-simpler
Simplify `ContentAddress`
2023-07-21 13:46:53 +02:00
Valentin Gagarin
0e4f6dfcf7 revert anchor prefix for builtin constants
the original change broke many pre-existing anchor links.

also change formatting of the constants listing slightly:
- the type should not be part of the anchor
- add highlight to the "impure only" note
2023-07-20 10:27:38 +02:00
John Ericson
caabc4f648 Feature gate DownstreamPlaceholder::unknownCaOutput
This is a part of CA derivations that we forgot to put behind the
experimental feature.

This was caught by @fricklerhandwerk in
https://github.com/NixOS/nix/pull/8369#discussion_r1258133719
2023-07-13 07:56:33 -04:00
John Ericson
4a880c3cc0
Merge pull request #8579 from obsidiansystems/findPath-cleanup-2
Further search path cleanups
2023-07-10 09:59:01 -04:00
Eelco Dolstra
fea7d3b1cd
Merge pull request #8681 from inclyc/libexpr/parser-move-noeffect
libexpr: remove std::move() for `basePath` in parser, it has no effect
2023-07-10 13:30:42 +02:00
Yingchi Long
3d74e7b811 libexpr: remove std::move() for basePath in parser, it has no effect 2023-07-10 12:02:29 +08:00
John Ericson
028b26a77f
Merge pull request #8370 from hercules-ci/fetchClosure-input-addressed
`fetchClosure`: input addressed and pure
2023-07-09 23:41:22 -04:00
John Ericson
be518e73ae Clean up SearchPath
- Better types

- Own header / C++ file pair

- Test factored out methods

- Pass parsed thing around more than strings

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2023-07-09 23:22:22 -04:00
John Ericson
87dcd09047 Clean up resolveSearchPathElem
We should use `std::optional<std::string>` not `std::pair<bool,
std::string>` for an optional string.
2023-07-09 23:13:30 -04:00
John Ericson
903700c5e1 Simplify ContentAddress
Whereas `ContentAddressWithReferences` is a sum type complex because different
varieties support different notions of reference, and
`ContentAddressMethod` is a nested enum to support that,
`ContentAddress` can be a simple pair of a method and hash.

`ContentAddress` does not need to be a sum type on the outside because
the choice of method doesn't effect what type of hashes we can use.

Co-Authored-By: Cale Gibbard <cgibbard@gmail.com>
2023-07-07 07:30:01 -04:00
Robert Hensing
b4b02d084f fetchClosure: Interleave the examples in the docs 2023-07-07 11:40:40 +02:00
Robert Hensing
537e8beb77
fetchClosure: Apply suggestions from code review
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
2023-07-07 11:00:40 +02:00
Yingchi Long
3c90340fe6 libexpr: use thread_local to make the parser thread-safe
If we call `adjustLoc`, the global variable `prev_yylloc` is shared
between threads and racy.

Currently, nix itself does not concurrently parsing files, but this is
helpful for libexpr users. (The parser is thread-safe except this.)
2023-07-03 16:05:43 +08:00
Robert Hensing
7b39a388b3
Merge pull request #8566 from inclyc/nixd/value-print-depth
libexpr: extend `Value::print` to allow limited depth
2023-07-01 20:08:52 +02:00
Robert Hensing
40052c7613 fetchClosure: Docs and error message improvements
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
2023-06-30 18:23:42 +02:00
Robert Hensing
50de11d662 doc: Improve fetchClosure documentation 2023-06-30 18:23:24 +02:00
Robert Hensing
dc79636007 fetchClosure: Refactor: replace enableRewriting
A single variable is nice and self-contained.
2023-06-30 18:22:47 +02:00
Robert Hensing
5bdca46117 fetchClosure: Split into three cases 2023-06-30 18:22:47 +02:00
Robert Hensing
55888633dd makeContentAddressed: Add single path helper 2023-06-30 18:22:47 +02:00
Robert Hensing
8dca95386c fetchClosure: Disallow toPath for inputAddressed = true 2023-06-30 18:22:47 +02:00
Robert Hensing
508aa58e67 fetchClosure: Always check that inputAddressed matches the result 2023-06-30 18:22:47 +02:00
Robert Hensing
ea30f152b7 fetchClosure: Allow input addressed paths in pure mode
When explicitly requested by the caller, as suggested in the meeting
(https://github.com/NixOS/nix/pull/8090#issuecomment-1531139324)

> @edolstra: { toPath } vs { fromPath } is too implicit

I've opted for the `inputAddressed = true` requirement, because it
we did not agree on renaming the path attributes.

> @roberth: more explicit
> @edolstra: except for the direction; not immediately clear in which direction the rewriting happens

This is in fact the most explicit syntax and a bit redundant, which is
good, because that redundancy lets us deliver an error message that
reminds expression authors that CA provides a better experience to
their users.
2023-06-30 18:22:43 +02:00
Robert Hensing
7e5b6d2c45 fetchClosure: Refactor: rename toCA -> enableRewriting 2023-06-30 18:19:56 +02:00
Robert Hensing
0f6d596df5 fetchClosure: Factor out attribute hint 2023-06-30 18:19:56 +02:00
Robert Hensing
1632f08ea2
Merge pull request #8600 from inclyc/libexpr/fix-leaking-in-stripIndentation
libexpr: fix leaking `es2` in stripIndentation (parser.y)
2023-06-29 11:31:53 +02:00
Yingchi Long
3468cbaf47 libexpr: fix leaking es2 in stripIndentation (parser.y) 2023-06-28 22:38:44 +08:00
John Ericson
22b278e011 Automatically document builtin constants
This is done in roughly the same way builtin functions are documented.

Also auto-link experimental features for primops, subsuming PR #8371.

Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
2023-06-27 09:37:54 -04:00
John Ericson
e8067daf09 Generialize showType 2023-06-27 09:11:42 -04:00
Eelco Dolstra
8e770dac9f
Merge pull request #8576 from obsidiansystems/findPath-cleanup
Use a struct not `std::pair` for `SearchPathElem`
2023-06-26 12:37:06 +02:00
Théophane Hufschmitt
60f06a1714
Merge pull request #5385 from Enzime/add/dirty-rev
Add `dirtyRev` and `dirtyShortRev` to `fetchGit`
2023-06-24 14:55:31 +02:00
Michael Hoang
a7b49086c7 Add dirtyRev and dirtyShortRev to fetchGit
Fixes #4682
2023-06-24 14:17:25 +10:00
John Ericson
484290a9e0 Use a struct not std::pair for SearchPathElem
I got very confused trying to keep all the `first` and `second` straight
reading the code, *especially* as there is also another `(boolean,
string)` pair type also being used.

Named fields is much better.

There are other cleanups that we can do (for example, the existing
TODO), but we can do them later. Doing them now would just make this
harder to review.
2023-06-23 12:01:10 -04:00
Yingchi Long
9d8c4ac446 libexpr: remove unused token ATTRPATH in token declaration 2023-06-23 13:35:41 +08:00
Yingchi Long
1400fde144 libexpr: extend Value::print to allow limited depth 2023-06-22 18:28:30 +08:00