This adds 4 tests which test the new external commands feature:

* ExternalCommand - Tests the expected usage of external command invoked
  via cabal-install
* ExternalCommandSetup - Tests that the ./Setup interface does not
  support external commands (#9403)
* ExternalCommandEnv - Tests that environment variables are set and
  preserved appropiately  (#9402)
* ExternalCommandHelp - Test that `cabal help <cmd>` is interpreted appropiately (#9404)

cabal-install-solver: fix pkgconf 1.9 --modversion regression

Only move code to Simple/GHC/Build*

Check that the numbers of *versions* output is equal to the number of pkgconf's

fixes #8923

The pkgconf behavior was reverted upstream in 2.0

(this should cover the case too of checking that equal pkgList lines are output also)

Fix assertion failure when combining build-tool-depends and --enable-documentation

The `setDocumentation` function was modifying the elaborated package
after the hash was computed. This led to the assertion failing as the
computed hash was different to what was computed in the initial install
plan.

Therefore in order to fix this we either needed to:

1. Set elabBuildHaddocks = False at the point where the hash is
   initially computed.
2. Verify that elabBuildHaddocks = True will not lead to unexpected
   results.

The latter has been implemented.

The elabBuildHaddocks option is only consulted in
`hasValidHaddockTargets`, at which point documentation building the
executable component is disabled because elabHaddockExecutables is
False.

In the added test we ensure this by checking that we didn't build
documentation for the executable which is built because of
build-tool-depends.

Fixes #6006 #8313

formatting: Add style-commit makefile target

This target allows you to format a range of commits, for example:

```
make style-commit COMMIT=HEAD~1
> Last commit is formatted
make style-commit COMMIT=abcde
> Commits between HEAD and abcde are formatted
```

* Add bootstrap postjob to CI config

Add a new job to the bootstrap.yml GitHub action config.
This job succeeds if, and only if, all the other bootstrap
jobs succeed.

* Do not run bootstrap CI jobs for documentation changes

The approach was already introduced in #9355 for the validate jobs.
This commit introduces the same change also for the bootstrap jobs.

* Also ignore CONTRIBUTING.md and README.md in CI

We do not run the entire CI suite for documentation changes.
Previously, only changes which were restricted to the 'docs/'
subdirectory were considered to be documentation changes.
With this commit we also recognize changes to README.md and
CONTRIBUTING.md as documentation changes.

* Document improved CI for documentation in CONTRIBUTING.md

The CONTRIBUTING.md file now mentions that documentation changes
do not waste expensive CI resources.

* Recognize all README.md in subdirs as documentation

Expensive CI jobs should not run on changes which affect only
README.md files.

Remove debug-conflict-sets flag from solver package

Fixes #8937.

The debug-conflict-sets build flag probably hasn't been used for a long time,
and it isn't currently tested. This commit removes the flag, converts the
ConflictSet type back to a newtype, and removes an unnecessary instance.

Add support for 64-bit SPARC as a separate architecture

Previously, sparc64 was defined as an alias for the 32-bit SPARC
architecture which was true while SPARC mainland was mostly 32
bits. More recently, 64-bit SPARC has become a port of its own,
so it needs to be treated as a separate architecture.

explain `merge+no rebase` in CONTRIBUTING.md

and a few typos while reviewing

Use linker capability detection to improve linker use

The function `comperSupportsGhciLibs` has been renamed to
`linkerSupportsGhciLibs` because its about the linker not the compiler.

The function `comperSupportsGhciLibs` was using the compiler version
as a proxy for whether the linker supports relocatable objects. Now
support for relocatable objects is detected by running the linker.

`ldProgram` gets configured in two places, a seemingly default and
a GHC specific version. The later needs to be updated so that it
first calls the default configuration and then the new GHC version.

Standard GNU `ld` ues `--relocatable` while `ld.gold` uses a `-relocatable`
flag (with a single `-`). Code will now detect both versions.

Fix the platform string for GNU/Hurd

Since version 9.4.7-1, ghc fails to build on the GNU/Hurd port of Debian,
see

https://buildd.debian.org/status/fetch.php?pkg=ghc&arch=hurd-i386&ver=9.4.7-1&stamp=1697717885&raw=0

Error, rule finished running but did not produce file:
  _build/stage0/lib/i386-gnu-ghc-9.4.6/ghc-boot-th-9.4.7/libHSghc-boot-th-9.4.7.a

and indeed, what did get produce was rather
_build/stage0/lib/i386-hurd-ghc-9.4.6/ghc-boot-th-9.4.7/libHSghc-boot-th-9.4.7.a
(i386-hurd instead of i386-gnu).

This is due to confusion between hurd and gnu in various places.  Apparently
previous versions of ghc were using gnu for the GNU/Hurd port, and thus
putting libraries etc. in i386-gnu. So we have to follow the existing
practice.

hurd: Enable using $ORIGIN in RPATH

GNU/Hurd fully supports RPATH and the $ORIGIN development, and we indeed
want to use it for relocatable installations shipped in Debian GNU/Hurd.

testsuite: Be explicit about runtime test dependencies

Issue #8356 reports occasional errors from running the testsuite about
multiple package versions available. This stems from the invokation of
`runghc` not being explicit about all dependencies of the testsuite.

The solution is provide a component in the cabal file which is explicit
about which packages the tests can depend on. This component has a
build-depends section which lists all the dependencies that the tests
require.

It would be better if this component was a library component but we
can't do this with a Custom setup because of limitations to do with
per-component builds.

Then we also enable `-hide-all-packages`, so the dependency will not be
available if it is not explicitly listed as a dependency.

You could also imagine a future where the Setup.hs script found the test
files and compiled a single executable which would run all the tests,
rather than invoking runghc on each one individually.

Fixes #8356

CI: Attempt to enable tests for 9.6.3 windows

There were two failing tests:

1. CCompilerOverride, was attempting to use gcc.exe rather than
   clang.exe without also overriding the C options which led to
   incorrect options being passed to gcc.exe. The fix is to override to
   clang.exe on ghc-9.4 or newer.
2. ForeignLibs exposes a bug in GHC
   (ghc/ghc#24185) and hence is
   skipped for GHCs newer than 9.4 where it was first introduced.

Towards fixing #8451, we just need to fix the shared library issue now.

* Fix Semigroup target instance

When two target names are the same, `mappend`ing them should not
error but just pick the first name.

* Add `desugarBuildToolSimple`

* Reimplement cabal check

* Reorder test output

* Fix autogen modules tests .cabal files

* Add a number of tests

* Add test for #7423

i.e. Do not warn on -O2 if under off-by-default package configuration
flag conditional.

* Add a regression for:

    * Add another -WErrr test
        This is to make sure we do *not* report it if it is under
        a user, off-by-default flag.
    * Add test for non manual user flags.
    * Add “absolute path in extra-lib-dirs” test
    * Add if/else test
    * Add “dircheck on abspath” check
    * Add Package version internal test
    * Add PackageVersionsStraddle test

* Add changelog for #8427

* Integrate various reviews

* Integrate Artem’s review

(review) Clarify `combineNames` documentation

By explaining the way it operates (working if the two names are equal
or one is empty) and renaming the function from `combineName` to
`combineNames`.

(review) Use guards instead of if/then/else

(review) Match inside argument list

(review) Replace “white” with “allow”

(review) Fix typo in comment

(review) Fix typo in Check module documentation

(review) Harmonise indentation for `data` decls

First field goes in a new line than the data constructor, so we
have more space.

(review) Rename `Prim` module to `Types`

(review) Add checkPackageFilesGPD

`checkPackageFiles` — which works on PD — was used to perform IO. We
introduce a function that does the same thing but works on GPD (which
is more principled).

`checkPackageFiles` cannot just be removed, since it is part of the
interface of Distribution.PackageDescription.Check. Deprecation can
be planned once “new check” is up and running.

* Integrate Andreas’ review

(review) Add named section to missing upper bound check

“miss upper bound” checks will now list target type and name (“On
executable 'myexe', these packages miss upper bounds”) for easier
fixing by the user.

(review) remove `cabal gen-bounds` suggestion

Reasonable as `cabal gen-bounds` is stricter than `cabal check`, see
https://github.com/haskell/cabal/pull/8427#issuecomment-1446712486


Once `gen-bounds` behaves in line with `check` we can readd the
suggestion.

(review) Do not warn on shared bounds

When a target which depends on an internal library shares some
dependencies with the latter, do not warn on upper bounds.

An example is clearer

    library
     build-depends: text < 5
    ⁝
     build-depends: myPackage,        ← no warning, internal
                    text,             ← no warning, shared bound
                    monadacme         ← warning!

* Integrate Artem’s review /II

(review) Split Check.hs

Check.hs has been split in multiple file, each une sub 1000 lines:

Check              857 lines
Check.Common       147 lines
Check.Conditional  204 lines
Check.Monad        352 lines
Check.Paths        387 lines
Check.Target       765 lines
Check.Warning      865 lines

Migration guide:
- Check              GPD/PD checks plus work-tree checks.
- Check.Common       common types and functions that are
                     *not* part of monadic checking setup.
- Check.Conditional  checks on CondTree and related matter
                     (variables, duplicate modules).
- Check.Monad        Backbone of the checks, monadic inter-
                     face and related functions.
- Check.Paths        Checks on files, directories, globs.
- Check.Target       Checks on realised targets (libraries,
                     executables, benchmarks, testsuites).
- Check.Warning      Datatypes and strings for warnings
                     and severities.

(review) remove useless section header

(review) Fix typo

(review) Add warnings documentation (list)

For each warning, we document constructor/brief description
in the manual.  This might not be much useful as not but it
will come handy when introducing `--ignore=WARN` and similar
flags.

* (review Andreas) Clarify CheckExplanation comment

Whoever modifies `CheckExplanation` data constructors needs to be
aware that the documentation in  doc/cabal-commands.rst  has to be
updated too.

* Move internal Check modules to `other-modules`

No need to expose Distribution.PackageDescription.Check.*
to the world. API for checking, for cabal-install and other
tools, should be in Distribution.PackageDescription.Check.

* Make fourmolu happy

Cabal codebase has now a formatter/style standard (see #8950).

“Ravioli ravioli, give me the formuoli”

* Do not check for OptO in scripts

See #8963 for reason and clarification requests.

* Remove useless PackageId parameter

It is now in the Reader part of CheckM monad.

* Do not check PVP on internal targets

Internal: testsuite, benchmark.
See #8361.

* Make hlint happy

* Fix #9122

When checking internal version ranges, we need to make sure we
are not mistaking a libraries with the same name but from different
packages. See #9132.

* Fix grammar

neither…nor, completing what done in #9162

* Integrate Brandon’s review: grammar

* Remove unnecessary `-fvia-C` check

Brandon’s review/II.

---------

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

* Add a 'cabal path' command.

* Formatting fix.

* Another formatting fix.

* Categorise "cabal path" as global command.

* Allow individual paths to be printed.

* Less duplication.

* Add config-file to "cabal path".

* Use sum type instead of strings.

* cabal path: support --installdir.

* Add documentation.

* Better text.

* Formatting.

* Add some tests.

* Improve tests.

* Add changelog entry.

* Mention "cabal path" in directory documentation.

---------

Co-authored-by: Artem Pelenitsyn <a.pelenitsyn@gmail.com>

Add test requirement to PR template

Adding test becomes a checkmark instead of “bonus points”.

Document --profiling-detail in setup-commands.

Fixes #9182

* Use PackageInfo for cabal-install version number

* Use Paths_cabal_install instead

* Adjust documentation

---------

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Add dependencies used by `PackageTests` to exe:cabal-tests

Hannes Siebenhandl authored 1 year ago and Mikolaj Konarski committed 1 year ago

The runner allows the tests to use extra dependencies and the custom Prelude
from 'cabal-testsuite'.
However, if the tests use a dependency, say 'directory', and there are two
packages with the same unit id available in the store, the test fails since
it doesn't know which one to pick.
By including an extra dependency to directory, we force the test runner to
use a specific version directory, fixing the test failure.

Require version 3,11 of Cabal to support --semaphore flag