v2-run needs a way to use package directory

[symbiont-sam-halliday]

Describe the bug

v2-run tasty uses the current working directory when invoking the tasty binary, but this breaks multi-package builds (i.e. projects with a cabal.project) that have test data in a specific location relative to the .cabal file.

For example, aeson-golden tests will fail because they expect to be run from the package directory, not the location of the cabal.project file.

To Reproduce
Steps to reproduce the behavior:

$ cd foo
$ cabal v2-run tasty

vs

$ cd ..
$ cabal v2-run foo:tasty

Expected behavior

The tests should run with the CWD set to the directory containing the .cabal file.

System information

• Operating system: N/A
• cabal, ghc versions: all released versions

** Other Context

Not only does this mean that running tests from the root dir vs the package dir produce different results, but stack uses the convention of always running tests from the dir containing the .cabal file and therefore this subtle change in behaviour makes it difficult to migrate from stack to cabal or for developers to have a choice of build tool on their project.

[phadej]

I’m pretty sure tests are run from pkg directory, otherwise `cabal v2-test Cabal:parser-tests` would fail. Which version of cabal-install do you have, is it a regression?

…

On 6 Aug 2019, at 12.46, Sam Halliday ***@***.***> wrote: Describe the bug v2-test uses the current working directory when invoking the test binary, but this breaks multi-package builds (i.e. projects with a cabal.project) that have test data in a specific location relative to the .cabal file. For example, aeson-golden tests will fail because they expect to be run from the package directory, not the location of the cabal.project file. To Reproduce Steps to reproduce the behavior: $ cd my-package $ cabal v2-test vs $ cd .. $ cabal v2-test Please use version-prefixed commands (e.g. v2-build or v1-build) to avoid ambiguity. Expected behavior The tests should run with the CWD set to the directory containing the .cabal file. System information Operating system: N/A cabal, ghc versions: all released versions ** Other Context Not only does this mean that running tests from the root dir vs the package dir produce different results, but stack uses the convention of always running tests from the dir containing the .cabal file and therefore this subtle change in behaviour makes it difficult to migrate from stack to cabal or for developers to have a choice of build tool on their project. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or mute the thread.

[symbiont-sam-halliday]

@phadej apologies, you're right... my reproduction is broken. This is actually a problem with using cabal v2-run foo:tasty to run tests, which is currently required because it is not possible to pass parameters such as -p Pattern to v2-test. I will update the description. (I wrote this bug report from some old notes, I got lazy and should have confirmed!)

An alternative solution to the core problem would be if something like cabal v2-test -O0 -- -p Pattern worked as expected.

[symbiont-sam-halliday]

Closing because I think this is more fundamentally dealt with by fixing #6114 which would allow v2-test to be used to run tests for this usecase.