Stack 3.9.1 has GHC's redundant backtrace, when tests fail

[NorfairKing]

Get rid of this when my test suite fails, please:

nix-ci-leader-gen> Test suite nix-ci-leader-gen-test failed

Error: [S-7282]
       Stack failed to execute the build plan.
       
       While executing the build plan, Stack encountered the error:
       
       Error: [S-1995]
       Test suite failure for package nix-ci-leader-gen-0.0.0
           nix-ci-leader-gen-test:  exited with: ExitFailure 1
       Logs printed to console
       
       HasCallStack backtrace:
         collectBacktraces, called at libraries/ghc-internal/src/GHC/Internal/Exception.hs:169:13 in ghc-internal:GHC.Internal.Exception
         toExceptionWithBacktrace, called at libraries/ghc-internal/src/GHC/Internal/IO.hs:260:11 in ghc-internal:GHC.Internal.IO
         throwIO, called at libraries/ghc-internal/src/GHC/Internal/Control/Exception/Base.hs:195:43 in ghc-internal:GHC.Internal.Control.Exception.Base

Most of my screen is filled up with this useless information.

All I need is:

Test suite nix-ci-leader-gen-test failed for package nix-ci-leader-gen-0.0.0

The call stack is especially egregious. I don't need to know where the code is defined GHC uses to implement the exception mechanism that you use to implement showing me failing tests.

[NorfairKing]

While we're on this subject;
A test suite not passing is not an "error" and definitely not a "failure".

It's a success that occurred during development working as intended.

[NorfairKing]

I don't mean to sound entitled, either. If you point me to the code I can try to fix it myself.

[mpilgrem]

I am stil looking into the history of this behaviour, but I think the 'full fat' message was introduced deliberately in Stack 0.1.1.0 in response to:

• single test suite failure should show entire log #388
• f38b913

GHC may have been less informative, back then.

The code that presents the full information is in Stack.Types.Build.Exception (instance Exception BuildException, displayException (TestSuiteFailure ident codes mlogFile bs)). The exception is thrown in Stack.Build.ExecutePackage.singleTest.

[NorfairKing]

@mpilgrem this is being fixed in GHC instead: https://gitlab.haskell.org/ghc/ghc/-/issues/26762

[mpilgrem]

Adding some further explanation here:

Stack 3.7.1 depends upon GHC 9.8.4 boot packages. So, stack test (for a test that fails) results in a message including (extract):

Error: [S-1995]
Test suite failure for package test6840-0.1.0.0
    test6840-test:  exited with: ExitFailure 1
Logs printed to console

Stack 3.9.1 depends upon GHC 9.10.3 boot packages. So, stack test results in a message (extract):

Error: [S-1995]
Test suite failure for package test6840-0.1.0.0
    test6840-test:  exited with: ExitFailure 1
Logs printed to console

HasCallStack backtrace:
  collectBacktraces, called at libraries\ghc-internal\src\GHC\Internal\Exception.hs:169:13 in ghc-internal:GHC.Internal.Exception
  toExceptionWithBacktrace, called at libraries\ghc-internal\src\GHC\Internal\IO.hs:260:11 in ghc-internal:GHC.Internal.IO
  throwIO, called at libraries\ghc-internal\src\GHC\Internal\Control\Exception\Base.hs:195:43 in ghc-internal:GHC.Internal.Control.Exception.Base

This changed behaviour of GHC is fixed in GHC 9.12.3 (which version is broken) and GHC 9.14.1. The master branch version of Stack can be built with GHC 9.12.3 and GHC 9.14.1. In both cases, stack test results in a message (extract):

Error: [S-1995]
Test suite failure for package test6840-0.1.0.0
    test6840-test:  exited with: ExitFailure 1
Logs printed to console

Stack will move on to a newer version of GHC when it is adopted as a Stackage LTS Haskell snapshot.