Commit Graph
2737 Commits
Author SHA1 Message Date
Maximilian Bosch 86eddb9e27 libexpr/flake: (opinionated) changes to interactive flake config
So I recently saw it the first time in the wild, I liked that you get
interactively asked about the nix.conf settings from the flake, but
there were a few minor things that I'd like to see changed:

* The `(y/N)` was somewhere in the middle of the line. Moved it to
  the end. At first I assumed it was a bug because another thread into
  my terminal while I was answering the question.

* I had to say no four times for a single flake with two options. So if
  you already know you don't want any of the config for _this_ flake, I
  found a `No to all` switch that ignores the rest of the nix.conf
  settings a little more ergonomic than having to stop the invocation,
  looking up the exact wording of `--no-accept-flake-config` and
  restarting it. Hence, I added it.

* Added a note where the choices which settings to trust are persisted.
  My initial assumption was that this went into `nix.conf` which is not
  writable on NixOS, so I said no there as well.

Change-Id: I0a0d9c403f0662df4707697a77f08e6cd003ec6f
2024-11-07 21:47:26 +01:00
Lulu 4ea8c9d643 Set c++ version to c++23
I followed @pennae's advice and moved the constructor definition of
`AttrName` from the header file `nixexpr.hh` to `nixexpr.cc`.

Change-Id: I733f56c25635b366b11ba332ccec38dd7444e793
2024-10-08 20:05:28 +02:00
Lulu 43e79f4434 Fix gcc warning -Wmissing-field-initializers
The approach that was taken here was to add default values to the type
definitions rather than specify them whenever they are missing.

Now the only remaining warning is '-Wunused-parameter' which @jade said
is usually counterproductive and that we can just disable it:
https://git.lix.systems/lix-project/lix/issues/456#issuecomment-6617

So this change adds the flags '-Wall', '-Wextra' and
'-Wno-unused-parameter', so that all warnings are enabled except for
'-Wunused-parameter'.

Change-Id: Ic223a964d67ab429e8da804c0721ba5e25d53012
2024-10-08 01:44:38 +00:00
Robert HensingandRebecca Turner ee0c195eba Split ignoreException to avoid suppressing CTRL-C
This splits `ignoreException` into `ignoreExceptionExceptInterrupt`
(which ignores all exceptions except `Interrupt`, which indicates a
SIGINT/CTRL-C) and `ignoreExceptionInDestructor` (which ignores all
exceptions, so that destructors do not throw exceptions).

This prevents many cases where Nix ignores CTRL-C entirely.
See: https://github.com/NixOS/nix/issues/7245

Upstream-PR: https://github.com/NixOS/nix/pull/11618
Change-Id: Ie7d2467eedbe840d1b9fa2e88a4e88e4ab26a87b
2024-10-01 15:49:56 -07:00
Maximilian Bosch 04daff94e3 libfetchers/git: restore compat with builtins.fetchGit from 2.3
Since fb38459d6e, each `ref` is appended
with `refs/heads` unless it starts with `refs/` already. This regressed
two use-cases that worked fine before:

* Specifying a commit hash as `ref`: now, if `ref` looks like a commit
  hash it will be directly passed to `git fetch`.

* Specifying a tag without `refs/tags` as prefix: now, the fetcher prepends
  `refs/*` to a ref that doesn't start with `refs/` and doesn't look
  like a commit hash. That way, both a branch and a tag specified in
  `ref` can be fetched.

  The order of preference in git is

  * file in `refs/` (e.g. `HEAD`)
  * file in `refs/tags/`
  * file in `refs/heads` (i.e. a branch)

  After fetching `refs/*`, ref is resolved the same way as git does.

Change-Id: Idd49b97cbdc8c6fdc8faa5a48bef3dec25e4ccc3
2024-09-28 14:52:06 +02:00
Rebecca Turner fc4a160878 repl-overlays: Provide an elaborate example
This is the repl overlay from my dotfiles, which I think provides a
reasonable and ergonomic set of variables. We can iterate on this over
time, or (perhaps?) provide a sentinel value like `repl-overlays =
<DEFAULT>` to include a "suggested default" overlay like this one.

Change-Id: I8eba3934c50fbac8367111103e66c7375b8d134e
2024-09-01 15:30:58 -07:00
Jade LovelaceandRebecca Turner 04f8a14833 tree-wide: shuffle headers around for about 30s compile time
This didn't really feel so worth it afterwards, but I did untangle a
bunch of stuff that should not have been tangled.

The general gist of this change is that variant bullshit was causing a
bunch of compile time, and it seems like the only way to deal with
variant induced compile time is to keep variant types out of headers.
Explicit template instantiation seems to do nothing for them.

I also seem to have gotten some back-end time improvement from
explicitly instantiating regex, but I don't know why. There is no
corresponding front-end time improvement from it: regex is still at the
top of the sinners list.

**** Templates that took longest to instantiate:
 15231 ms: std::basic_regex<char>::_M_compile (28 times, avg 543 ms)
 15066 ms: std::__detail::_Compiler<std::regex_traits<char>>::_Compiler (28 times, avg 538 ms)
 12571 ms: std::__detail::_Compiler<std::regex_traits<char>>::_M_disjunction (28 times, avg 448 ms)
 12454 ms: std::__detail::_Compiler<std::regex_traits<char>>::_M_alternative (28 times, avg 444 ms)
 12225 ms: std::__detail::_Compiler<std::regex_traits<char>>::_M_term (28 times, avg 436 ms)
 11363 ms: nlohmann::basic_json<>::parse<const char *> (21 times, avg 541 ms)
 10628 ms: nlohmann::basic_json<>::basic_json (109 times, avg 97 ms)
 10134 ms: std::__detail::_Compiler<std::regex_traits<char>>::_M_atom (28 times, avg 361 ms)

Back-end time before messing with the regex:
**** Function sets that took longest to compile / optimize:
  8076 ms: void boost::io::detail::put<$>(boost::io::detail::put_holder<$> cons... (177 times, avg 45 ms)
  4382 ms: std::_Rb_tree<$>::_M_erase(std::_Rb_tree_node<$>*) (1247 times, avg 3 ms)
  3137 ms: boost::stacktrace::detail::to_string_impl_base<boost::stacktrace::de... (137 times, avg 22 ms)
  2896 ms: void boost::io::detail::mk_str<$>(std::__cxx11::basic_string<$>&, ch... (177 times, avg 16 ms)
  2304 ms: std::_Rb_tree<$>::_M_get_insert_hint_unique_pos(std::_Rb_tree_const_... (210 times, avg 10 ms)
  2116 ms: bool std::__detail::_Compiler<$>::_M_expression_term<$>(std::__detai... (112 times, avg 18 ms)
  2051 ms: std::_Rb_tree_iterator<$> std::_Rb_tree<$>::_M_emplace_hint_unique<$... (244 times, avg 8 ms)
  2037 ms: toml::result<$> toml::detail::sequence<$>::invoke<$>(toml::detail::l... (93 times, avg 21 ms)
  1928 ms: std::__detail::_Compiler<$>::_M_quantifier() (28 times, avg 68 ms)
  1859 ms: nlohmann::json_abi_v3_11_3::detail::serializer<$>::dump(nlohmann::js... (41 times, avg 45 ms)
  1824 ms: std::_Function_handler<$>::_M_manager(std::_Any_data&, std::_Any_dat... (973 times, avg 1 ms)
  1810 ms: std::__detail::_BracketMatcher<$>::_BracketMatcher(std::__detail::_B... (112 times, avg 16 ms)
  1793 ms: nix::fetchers::GitInputScheme::fetch(nix::ref<$>, nix::fetchers::Inp... (1 times, avg 1793 ms)
  1759 ms: std::_Rb_tree<$>::_M_get_insert_unique_pos(std::__cxx11::basic_strin... (281 times, avg 6 ms)
  1722 ms: bool nlohmann::json_abi_v3_11_3::detail::parser<$>::sax_parse_intern... (19 times, avg 90 ms)
  1677 ms: boost::io::basic_altstringbuf<$>::overflow(int) (194 times, avg 8 ms)
  1674 ms: std::__cxx11::basic_string<$>::_M_mutate(unsigned long, unsigned lon... (249 times, avg 6 ms)
  1660 ms: std::_Rb_tree_node<$>* std::_Rb_tree<$>::_M_copy<$>(std::_Rb_tree_no... (304 times, avg 5 ms)
  1599 ms: bool nlohmann::json_abi_v3_11_3::detail::parser<$>::sax_parse_intern... (19 times, avg 84 ms)
  1568 ms: void std::__detail::_Compiler<$>::_M_insert_bracket_matcher<$>(bool) (112 times, avg 14 ms)
  1541 ms: std::__shared_ptr<$>::~__shared_ptr() (531 times, avg 2 ms)
  1539 ms: nlohmann::json_abi_v3_11_3::detail::serializer<$>::dump_escaped(std:... (41 times, avg 37 ms)
  1471 ms: void std::__detail::_Compiler<$>::_M_insert_character_class_matcher<... (112 times, avg 13 ms)

After messing with the regex (notice std::__detail::_Compiler vanishes
here, but I don't know why):

**** Function sets that took longest to compile / optimize:
  8054 ms: void boost::io::detail::put<$>(boost::io::detail::put_holder<$> cons... (177 times, avg 45 ms)
  4313 ms: std::_Rb_tree<$>::_M_erase(std::_Rb_tree_node<$>*) (1217 times, avg 3 ms)
  3259 ms: boost::stacktrace::detail::to_string_impl_base<boost::stacktrace::de... (137 times, avg 23 ms)
  3045 ms: void boost::io::detail::mk_str<$>(std::__cxx11::basic_string<$>&, ch... (177 times, avg 17 ms)
  2314 ms: std::_Rb_tree<$>::_M_get_insert_hint_unique_pos(std::_Rb_tree_const_... (207 times, avg 11 ms)
  1923 ms: std::_Rb_tree_iterator<$> std::_Rb_tree<$>::_M_emplace_hint_unique<$... (216 times, avg 8 ms)
  1817 ms: bool nlohmann::json_abi_v3_11_3::detail::parser<$>::sax_parse_intern... (18 times, avg 100 ms)
  1816 ms: toml::result<$> toml::detail::sequence<$>::invoke<$>(toml::detail::l... (93 times, avg 19 ms)
  1788 ms: nlohmann::json_abi_v3_11_3::detail::serializer<$>::dump(nlohmann::js... (40 times, avg 44 ms)
  1749 ms: std::_Rb_tree<$>::_M_get_insert_unique_pos(std::__cxx11::basic_strin... (278 times, avg 6 ms)
  1724 ms: std::__cxx11::basic_string<$>::_M_mutate(unsigned long, unsigned lon... (248 times, avg 6 ms)
  1697 ms: boost::io::basic_altstringbuf<$>::overflow(int) (194 times, avg 8 ms)
  1684 ms: nix::fetchers::GitInputScheme::fetch(nix::ref<$>, nix::fetchers::Inp... (1 times, avg 1684 ms)
  1680 ms: std::_Rb_tree_node<$>* std::_Rb_tree<$>::_M_copy<$>(std::_Rb_tree_no... (303 times, avg 5 ms)
  1589 ms: bool nlohmann::json_abi_v3_11_3::detail::parser<$>::sax_parse_intern... (18 times, avg 88 ms)
  1483 ms: non-virtual thunk to boost::wrapexcept<$>::~wrapexcept() (181 times, avg 8 ms)
  1447 ms: nlohmann::json_abi_v3_11_3::detail::serializer<$>::dump_escaped(std:... (40 times, avg 36 ms)
  1441 ms: std::__shared_ptr<$>::~__shared_ptr() (496 times, avg 2 ms)
  1420 ms: boost::stacktrace::basic_stacktrace<$>::init(unsigned long, unsigned... (137 times, avg 10 ms)
  1396 ms: boost::basic_format<$>::~basic_format() (194 times, avg 7 ms)
  1290 ms: std::__cxx11::basic_string<$>::_M_replace_cold(char*, unsigned long,... (231 times, avg 5 ms)
  1258 ms: std::vector<$>::~vector() (354 times, avg 3 ms)
  1222 ms: std::__cxx11::basic_string<$>::_M_replace(unsigned long, unsigned lo... (231 times, avg 5 ms)
  1194 ms: std::_Rb_tree<$>::_M_get_insert_hint_unique_pos(std::_Rb_tree_const_... (49 times, avg 24 ms)
  1186 ms: bool tao::pegtl::internal::sor<$>::match<$>(std::integer_sequence<$>... (1 times, avg 1186 ms)
  1149 ms: std::__detail::_Executor<$>::_M_dfs(std::__detail::_Executor<$>::_Ma... (70 times, avg 16 ms)
  1123 ms: toml::detail::sequence<$>::invoke(toml::detail::location&) (69 times, avg 16 ms)
  1110 ms: nlohmann::json_abi_v3_11_3::basic_json<$>::json_value::destroy(nlohm... (55 times, avg 20 ms)
  1079 ms: std::_Function_handler<$>::_M_manager(std::_Any_data&, std::_Any_dat... (541 times, avg 1 ms)
  1033 ms: nlohmann::json_abi_v3_11_3::detail::lexer<$>::scan_number() (20 times, avg 51 ms)

Change-Id: I10af282bcd4fc39c2d3caae3453e599e4639c70b
2024-08-28 09:55:05 -07:00
Jade LovelaceandRebecca Turner 0cc285f87b treewide: fix a bunch of lints
Fixes:
- Identifiers starting with _ are prohibited
- Some driveby header dependency cleaning which wound up with doing some
  extra fixups.
- Fucking C style casts, man. C++ made these 1000% worse by letting you
  also do memory corruption with them with references.
  - Remove casts to Expr * where ExprBlackHole is an incomplete type by
    introducing an explicitly-cast eBlackHoleAddr as Expr *.
  - An incredibly illegal cast of the text bytes of the StorePath hash
    into a size_t directly. You can't DO THAT.

    Replaced with actually parsing the hash so we get 100% of the bits
    being entropy, then memcpying the start of the hash. If this shows
    up in a profile we should just make the hash parser faster with a
    lookup table or something sensible like that.
  - This horrendous bit of UB which I thankfully slapped a deprecation
    warning on, built, and it didn't trigger anywhere so it was dead
    code and I just deleted it. But holy crap you *cannot* do that.

    inline void mkString(const Symbol & s)
    {
        mkString(((const std::string &) s).c_str());
    }
- Some wrong lints. Lots of wrong macro lints, one wrong
  suspicious-sizeof lint triggered by the template being instantiated
  with only pointers, but the calculation being correct for both
  pointers and not-pointers.
- Exceptions in destructors strike again. I tried to catch the
  exceptions that might actually happen rather than all the exceptions
  imaginable. We can let the runtime hard-kill it on other exceptions
  imo.

Change-Id: I71761620846cba64d66ee7ca231b20c061e69710
2024-08-26 16:13:03 -07:00
Alois Wohlschlager e3c289dbe9 libutil/config: unify path setting types
There have been multiple setting types for paths that are supposed to be
canonicalised, depending on whether zero or one, one, or any number of paths is
to be specified. Naturally, they behaved in slightly different ways in the
code. Simplify things by unifying them and removing special behaviour (mainly
the "multiple paths type can coerce to boolean" thing).

Change-Id: I7c1ce95e9c8e1829a866fb37d679e167811e9705
2024-08-21 17:57:23 +02:00
piegames 0edfea450b libexpr: Soft-deprecate ancient let syntax
Change-Id: I6802b26f038578870ea1fa1ed298f0c4b1f29c4a
2024-08-21 12:59:03 +02:00
piegames 7210ed1b87 libexpr: Soft-deprecate __overrides
Change-Id: I787e69e1dad6edc5ccdb747b74a9ccd6e8e13bb3
2024-08-21 06:55:52 +00:00
Maximilian Bosch 040e783232 flake: don't refetch unmodified inputs by recursive follows
Closes #460

I managed to trigger the issue by having the following inputs (shortened):

    authentik-nix.url = "github:nix-community/authentik-nix";
    authentik-nix.inputs.poetry2nix.inputs.nixpkgs.follows = "nixpkgs";

When evaluating this using

    nix-eval-jobs --flake .#hydraJobs

I got the following error:

    error: cannot update unlocked flake input 'authentik-nix/poetry2nix' in pure mode

The issue we have here is that `authentik-nix/poetry2nix` was written
into the `overrideMap` which caused Nix to assume it's a new input and
tried to refetch it (#460) or errored out in pure mode
(nix-eval-jobs / Hydra).

The testcase unfortunately only involves checking for the output log
and makes sure that something *is* logged on the first fetch so that
the test doesn't rot when the logging changes since I didn't
manage to trigger the error above with the reproducer from #460. In
fact, I only managed to trigger the `cannot update unlocked flake input`
error in this context with `nix-eval-jobs`.

Change-Id: Ifd00091eec9a0067ed4bb3e5765a15d027328807
2024-08-19 19:57:12 +00:00
piegames 278fddc317 libexpr: Deprecate URL literals
Closes #437.

Change-Id: I9f67fc965bb4a7e7fd849e5067ac1cb3bab064cd
2024-08-17 20:31:57 +02:00
piegames 49d61b2e4b libexpr: Introduce Deprecated features
They are like experimental features, but opt-in instead of opt-out. They
will allow us to gracefully remove language features. See #437

Change-Id: I9ca04cc48e6926750c4d622c2b229b25cc142c42
2024-08-17 19:47:51 +02:00
Qyriad 0787dcf5f6 libexpr: move Value implementations out of eval.cc
Change-Id: I2ce8a9713533888b3d109a56947156eb3a5ab492
2024-08-08 22:01:12 -06:00
jadeandGerrit Code Review 757041c3e7 Merge changes I526cceed,Ia4e2f1fa,I22e66972,I9fbd55a9,Ifca22e44 into main
* changes:
  sqlite: add a Use::fromStrNullable
  util: implement charptr_cast
  tree-wide: fix a pile of lints
  refactor: make HashType and Base enum classes for type safety
  build: integrate clang-tidy into CI
2024-08-08 22:43:10 +00:00
Jade Lovelace e34833c025 tree-wide: fix a pile of lints
This:
- Converts a bunch of C style casts into C++ casts.
- Removes some very silly pointer subtraction code (which is no more or
  less busted on i686 than it began)
- Fixes some "technically UB" that never had to be UB in the first
  place.
- Makes finally follow the noexcept status of the inner function. Maybe
  in the future we should ban the function from not being noexcept, but
  that is not today.
- Makes various locally-used exceptions inherit from std::exception.

Change-Id: I22e66972602604989b5e494fd940b93e0e6e9297
2024-08-08 14:53:17 -07:00
Jade Lovelace 370ac940dd refactor: make HashType and Base enum classes for type safety
Change-Id: I9fbd55a9d50464a56fe11cb42a06a206914150d8
2024-08-08 14:53:17 -07:00
piegames 28ae24f3f7 libexpr: Add experimental pipe operator
The |> operator is a reverse function operator with low binding strength
to replace lib.pipe. Implements RFC 148, see the RFC text for more
details. Closes #438.

Change-Id: I21df66e8014e0d4dd9753dd038560a2b0b7fd805
2024-08-08 11:13:53 +02:00
piegames ec7552ff74 libexpr/parser: Test experimental features
Currently, the parser relies on the global experimental feature flags.
In order to properly test conditional language features, we instead need
to pass it around in the parser::State.

This means that the parser cannot cache the result of isEnabled anymore,
which wouldn't necessarily hurt performance if the function didn't
perform a linear search on the list of enabled features on every single
call. While we could simply evaluate once at the start of parsing and
cache the result in the parser state, the more sustainable solution
would be to fix `isEnabled` such that all callers may profit from the
performance improvement.

Change-Id: Ic9b9c5d882b6270e1114988b63e6064d36c25cf2
2024-08-07 13:07:50 +00:00
Maximilian BoschandGerrit Code Review 27a63db710 Merge "fix: warn and document when advanced attributes will have no impact due to __structuredAttrs" into main 2024-08-07 10:38:39 +00:00
alois31andGerrit Code Review 780998f4ea Merge "package: improve support for building without BDW-GC" into main 2024-08-07 07:07:28 +00:00
Jade Lovelace ca9d3e6e00 tree-wide: fix various lint warnings
Change-Id: I0fc80718eb7e02d84cc4b5d5deec4c0f41116134
2024-08-04 20:55:45 -07:00
Tom BereknyeiandMaximilian Bosch 7fc481396c fix: warn and document when advanced attributes will have no impact due to __structuredAttrs
Backport of https://github.com/NixOS/nix/pull/10884.

Change-Id: I82cc2794730ae9f4a9b7df0185ed0aea83efb65a
2024-08-03 13:32:51 +02:00
Alois Wohlschlager 58758c0f87 package: improve support for building without BDW-GC
Expose an option for disabling the BDW-GC build dependency entirely. Fix the
place where one of its headers was included (unnecessarily) without proper
guarding. Finally, use this machinery to exclude BDW-GC from the ASAN builds
entirely (its usage has already been disabled due to compatibility issues
anyway), to ensure this configuration is not regressed again.

Change-Id: I2ebe8094abf67e7d1e99eed971de3e99d071c10b
2024-08-03 06:14:41 +02:00
Maximilian BoschandGerrit Code Review 3bb8c627ae Merge "Reapply "libfetchers: make attribute / URL query handling consistent"" into main 2024-08-02 04:50:25 +00:00
Maximilian BoschandJade Lovelace 87fd1f024c Reapply "libfetchers: make attribute / URL query handling consistent"
The original attempt at this introduced a regression; this commit
reverts the revert and fixes the regression.

This reverts commit 3e151d4d77.

Fix to the regression:

flakeref: fix handling of `?dir=` param for flakes in subdirs

As reported in #419[1], accessing a flake in a subdir of a Git
repository fails with the previous commit[2] applied with the error

    error: unsupported Git input attribute 'dir'

The problem is that the `dir`-param is inserted into the parsed URL if a
flake is fetched from the subdir of a Git repository. However, for the
fetching part this isn't even needed. The fix is to just pass `subdir`
as second argument to `FlakeRef` (which needs a `basedir` that can be
empty) and leave the parsedURL as-is.

Added a regression test to make sure we don't run into this again.

[1] https://git.lix.systems/lix-project/lix/issues/419
[2] e22172aaf6b6a366cecd3c025590e68fa2b91bcc,
    originally 3e151d4d77

Change-Id: I2c72d5a32e406a7ca308e271730bd0af01c5d18b
2024-08-01 15:41:30 -07:00
QyriadandGerrit Code Review 61a93d5308 Merge changes Icc4747ae,Id4717b5b,Ie3ddb3d0,Ic4d93a08,I00d9ff70 into main
* changes:
  remove unused headers in installable-attr-path
  libexpr: include the type of the non-derivation value in the type error
  libexpr: mild cleanup to getDerivations
  libexpr: DrvInfo: remove unused bad-citizen constructor
  cleanup and slightly refactor DrvInfo::queryOutputs
2024-08-01 16:25:43 +00:00
Qyriad 4f6a3d7e9e libexpr: include the type of the non-derivation value in the type error
Change-Id: Id4717b5b0df7c09b0dbf17e642d8713a0a3efbae
2024-08-01 00:37:03 +00:00
Qyriad 5ffed6d06a libexpr: mild cleanup to getDerivations
Shuffled the logic around a bit so the shorter code paths are early
returns, added comments, etc.

Should be NFC.

Change-Id: Ie3ddb3d0eddd614d6f8c37bf9a4d5a50282084ea
2024-08-01 00:36:55 +00:00
Qyriad 6a30ea0cc4 libexpr: DrvInfo: remove unused bad-citizen constructor
DrvInfo's constructor that only takes `EvalState` leaves everything else
empty; a DrvInfo which has no iota of information about the derivation
it represents is not useful, and was not used anywhere.

Change-Id: Ic4d93a08cb2748b8cef9a61e41e70404834b23f9
2024-08-01 00:36:41 +00:00
Qyriad eb18dcb0ea cleanup and slightly refactor DrvInfo::queryOutputs
Change-Id: I00d9ff707fe61995737b86af6d2eaa1e4d8116ff
2024-08-01 00:36:27 +00:00
Qyriadandeldritch horrors ddfca6e81b libexpr: implement actual constructors for nix::Value
Change-Id: Iebc2bb4e4ea5e93045afe47677df756de4ec4d05
2024-07-31 15:38:37 +02:00
Pierre BourdonandGerrit Code Review 73c013a5df Merge "libexpr/gc-alloc: fix compilation with !HAVE_BOEHMGC" into main 2024-07-22 23:14:59 +00:00
Pierre Bourdon e76245f8e9 libexpr/gc-alloc: fix compilation with !HAVE_BOEHMGC
Fixes: 72ee25b402
Change-Id: Ib59386af1415a8ed4b53af24ec22a4ffa5e5877d
2024-07-23 00:50:09 +02:00
eldritch horrors c74eb81356 enable -Werror=suggest-override
*accidentally* overriding a function is almost guaranteed to be an
error. overriding a function without labeling it as such is merely
bad style, but bad style that makes the code harder to understand.

Change-Id: Ic0594f3d1604ab6b3c1a75cb5facc246effe45f0
2024-07-22 16:26:55 +00:00
eldritch horrors 0463cf2aef libexpr: fix -Wunused-const-variable warning
Change-Id: Ib986ece0ab2eff83e7abd7f1f915cd8f761827ad
2024-07-22 16:26:55 +00:00
Qyriad 72ee25b402 libexpr: add a strongly typed version of gcAllocBytes()
This commit adds a new helper template function to gc-alloc.hh (which is
probably where you want to look at first, O great reviewer [custom file
ordering in review diffs when]), which uses a type argument to determine
the size to allocate, rather than making the caller use sizeof().

Change-Id: Ib5d138d91a28bdda304a80db24ea9fb08669ad22
2024-07-20 20:20:01 +00:00
Qyriad e67dac1d74 libexpr: rename confusing makeImmutableString -> gcCopyStringIfNeeded
The purpose of this function has little to do with immutability. Value's
strings are never mutated, and the point of this function is to
singleton empty strings.

Change-Id: Ifd41dd952409d54e4d3de9ab59064e6928b0e480
2024-07-20 20:20:01 +00:00
Qyriad a3361557e3 libexpr: refactor gc-agnostic helpers into one place
Change-Id: Icc4b367e4f670d47256f62a3a002cd248a5c2d3b
2024-07-20 20:20:01 +00:00
jadeandGerrit Code Review 22252825c4 Merge changes Id8b3d289,Ib75ab5b8,I3792eeb3 into main
* changes:
  Fixup a bunch of references to nixos.org manuals
  Add release notes for removing overflow from Nix language
  expr: fix a compiler warning about different signs in comparison
2024-07-19 18:52:46 +00:00
Jade Lovelace 26e56780ca Fixup a bunch of references to nixos.org manuals
(plus one reference to CppNix github)

Change-Id: Id8b3d2897f3b54e286861805cfd421adc4d5de47
2024-07-18 19:27:33 +00:00
Jade Lovelace 50a63f8435 expr: fix a compiler warning about different signs in comparison
We know that variable is >=0, so we can just cast it to unsigned.

Change-Id: I3792eeb3ca43e6a507cc44c1a70584d42b2acd7b
2024-07-18 19:27:33 +00:00
Alois Wohlschlager 40c39aa5d2 libexpr/print: do not show elided nested items when there are none
When the configured maximum depth has been reached, attribute sets and lists
are printed with ellipsis to indicate the elision of nested items. Previously,
this happened even in case the structure being printed is empty, so that such
items do not in fact exist. This is confusing, so stop doing it.

Change-Id: I0016970dad3e42625e085dc896e6f476b21226c9
2024-07-18 18:41:34 +02:00
Alois Wohlschlager b5da823138 libexpr/print: never show empty attrsets or derivations as «repeated»
The repeated value detection logic exists so that the occurrence of large
common substructures does not fill up the screen or the computer's memory.
However, empty attribute sets and derivations (when their detection is enabled)
are always cheap to print, and in practice I have observed them to make up a
significant majority of the cases where I was annoyed by the repeated value
detection kicking in. Furthermore, `nix-instantiate --eval` already disables
this logic for empty attribute sets, and empty lists are already exempted
everywhere. For these reasons, always print empty attribute sets and
derivations as what they are.

Change-Id: I5dac8e7739f9d726b76fd0521ec46f38af94463f
2024-07-18 18:41:34 +02:00
Alois WohlschlagerandRobert Hensing 81a0624d76 libexpr/print: pretty-print idempotently
When pretty-printing is enabled, previously an unforced thunk would trigger
indentation, even when it subsequently does not evaluate to a nested structure.
The resulting output looked inconsistent, and furthermore pretty-printing was
not idempotent (since pretty-printing the same value again, which is now fully
evaluated, will not trigger indentation).
When strict evaluation is enabled, force the item before inspecting its type,
so that it is properly known whether it contains a nested structure.
Furthermore, there is no need to cause indentation for unforced thunks, since
the very next operation will be printing them as `«thunk»`.

This is mostly a port of https://github.com/NixOS/nix/pull/11100 , but we only
force the item when it's going to be forced anyway due to strict
pretty-printing, and a new test was written since the REPL testing framework in
Lix is different.

Co-Authored-By: Robert Hensing <robert@roberthensing.nl>
Change-Id: Ib7560fe531d09e05ca6b2037a523fe21a26d9d58
2024-07-18 18:41:28 +02:00
eldritch horrors ef0de7c79f remove boost coroutine references
we no longer need these since sinkToSource and sourceToSink are gone.

Change-Id: Ibbf440e2cf71bf3e9f3b833af2d78a21fb1b3193
2024-07-16 01:50:16 +00:00
eldritch horrors dfedbc154f remove sourceToSink, sinkToSource, and boehm patch
Change-Id: I1379841299713175d0225b82a67f50660f9eb5e2
2024-07-16 01:50:16 +00:00
NaN 505640baec libexpr/eval.cc: remove unnecessary C string conversion
Change-Id: I5b7c21df84ff8ff64cf6a1e261fc3729a06bd4f6
2024-07-14 02:13:58 +00:00
Jade Lovelace 917c9bdee7 language: cleanly ban integer overflows
This also bans various sneaking of negative numbers from the language
into unsuspecting builtins as was exposed while auditing the
consequences of changing the Nix language integer type to a newtype.

It's unlikely that this change comprehensively ensures correctness when
passing integers out of the Nix language and we should probably add a
checked-narrowing function or something similar, but that's out of scope
for the immediate change.

During the development of this I found a few fun facts about the
language:
- You could overflow integers by converting from unsigned JSON values.
- You could overflow unsigned integers by converting negative numbers
  into them when going into Nix config, into fetchTree, and into flake
  inputs.

  The flake inputs and Nix config cannot actually be tested properly
  since they both ban thunks, however, we put in checks anyway because
  it's possible these could somehow be used to do such shenanigans some
  other way.

Note that Lix has banned Nix language integer overflows since the very
first public beta, but threw a SIGILL about them because we run with
-fsanitize=signed-overflow -fsanitize-undefined-trap-on-error in
production builds. Since the Nix language uses signed integers, overflow
was simply undefined behaviour, and since we defined that to trap, it
did.

Trapping on it was a bad UX, but we didn't even entirely notice
that we had done this at all until it was reported as a bug a couple of
months later (which is, to be fair, that flag working as intended), and
it's got enough production time that, aside from code that is IMHO buggy
(and which is, in any case, not in nixpkgs) such as
https://git.lix.systems/lix-project/lix/issues/445, we don't think
anyone doing anything reasonable actually depends on wrapping overflow.

Even for weird use cases such as doing funny bit crimes, it doesn't make
sense IMO to have wrapping behaviour, since two's complement arithmetic
overflow behaviour is so *aggressively* not what you want for *any* kind
of mathematics/algorithms. The Nix language exists for package
management, a domain where bit crimes are already only dubiously in
scope to begin with, and it makes a lot more sense for that domain for
the integers to never lose precision, either by throwing errors if they
would, or by being arbitrary-precision.

This change will be ported to CppNix as well, to maintain language
consistency.

Fixes: https://git.lix.systems/lix-project/lix/issues/423

Change-Id: I51f253840c4af2ea5422b8a420aa5fafbf8fae75
2024-07-13 00:59:33 +02:00