Add testing support on ghc >= 9.4

[jimbob88]

Then, shall we drop support for 9.0 and 9.2 and proceed with 9.4 if the cost of support is low? I’m also thinking of adding CI settings for 9.6 and later.

This pull request adds testing on 9.6, 9.8, 9.12 and drops support for testing on 9.2 and 9.0. I also removed 9.0 and 9.2 from the supported versions in the cabal package.

(If the output changes in 9.12, it seems like preparing a new ghc.output specifically for 9.12 would be a good approach.)
I was incorrect with my original assessment. It changes for all of ghc 9 it seems. I have updated the test to work in a different way. The new output for ghc >= 9 looks as follows:

example: Uncaught exception ghc-internal:GHC.Internal.Exception.ErrorCall:

fError

HasCallStack backtrace:
  error, called at example/Main.hs:47:10 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  fError, called at example/Main.hs:43:11 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f10, called at example/Main.hs:40:6 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f9, called at example/Main.hs:37:11 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f8, called at example/Main.hs:33:16 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f7, called at example/Main.hs:29:11 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f6, called at example/Main.hs:25:15 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f5, called at example/Main.hs:21:8 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f4, called at example/Main.hs:17:6 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f3, called at example/Main.hs:13:6 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f2, called at example/Main.hs:10:6 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  f1, called at example/Main.hs:7:14 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main
  main, called at example/Main.hs:7:1 in haskell-stack-trace-plugin-0.1.3.0-inplace-example:Main

However, when being run in the tests, it also adds the current commit hash as follows (see here):

example: Uncaught exception ghc-internal:GHC.Internal.Exception.ErrorCall:
                 
                 fError
                 
                 HasCallStack backtrace:
                   error, called at example/Main.hs:47:10 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   fError, called at example/Main.hs:43:11 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f10, called at example/Main.hs:40:6 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f9, called at example/Main.hs:37:11 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f8, called at example/Main.hs:33:16 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f7, called at example/Main.hs:29:11 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f6, called at example/Main.hs:25:15 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f5, called at example/Main.hs:21:8 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f4, called at example/Main.hs:17:6 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f3, called at example/Main.hs:13:6 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f2, called at example/Main.hs:10:6 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   f1, called at example/Main.hs:7:14 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main
                   main, called at example/Main.hs:7:1 in haskell-stack-trace-plugin-0.1.3.0-e-example-2c146cc2a526fda8afc7cbecc1799d00a2e300df7bab1279aacb0d6bf26e10db:Main

Due to this change, I updated the tests to use a regex and extract each function that appears in the call stack. It then checks that every function that should appear in the stack trace, appears in that order.

-- | Extracts the function names of all functions that appear in a stack trace
extractStackTraceFunctions :: String -> [String]
extractStackTraceFunctions input = map extractFunctionName matches
 where
  regex = [r|[ ]*([A-Za-z0-9]+), called at example/Main.hs:[0-9]+:[0-9]+ in [^:]+:Main|] :: String
  matches = (input =~ regex) :: [[String]]
  extractFunctionName :: [String] -> String
  extractFunctionName (_ : name : _) = name
  extractFunctionName _ = error "Regex match failed"

spec :: Spec
spec = do
  output <- runIO exe
  let outputStr = BS.unpack output
  let extractedFunctions = extractStackTraceFunctions outputStr

  -- each of these exceptions should appear in the stack trace
  let expectedFunctions = ["error", "fError", "f10", "f9", "f8", "f7", "f6", "f5", "f4", "f3", "f2", "f1", "main"] :: [String]

  it "integration test" $ extractedFunctions `shouldBe` expectedFunctions

Thank you. Are you currently working on the support for ghc-9.4?

This pull request fixes the tests on 9.4 (the code worked but the tests couldn't run due to a version constraint).

[waddlaw]

LGTM

[waddlaw]

I'd like to add support for 9.10 as well, but I think it would be better to handle it in a separate PR.

[jimbob88]

I have tested locally and 9.10.1 works on my computer. Haven't tried running the tests in CI or locally though.

[waddlaw]

@jimbob88 Thank you for your contribution! 👍