Consider avoiding partial pattern matches in tests #495
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joelburget
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These locations trigger errors on ghc 8.6 for missing `MonadFail` instances. Fixes #495.
joelburget
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These locations trigger errors on ghc 8.6 for missing `MonadFail` instances. Fixes #495.
fosskers
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May 20, 2019
These locations trigger errors on ghc 8.6 for missing `MonadFail` instances. Fixes #495.
sirlensalot
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May 24, 2019
* Massaging upper bounds This allows the library to build (and be depended on) without "breaking open" the build with heavy-hammers like `--allow-newer` when compiling with GHC 8.6. The test suite still does not build, due to some naughty partial pattern matches. * Remove partial pattern matches from hedgehog generators. These locations trigger errors on ghc 8.6 for missing `MonadFail` instances. Fixes #495. * Fix remaining monad pattern matches for ghc 8.6. Tested with `stack test` (all passing). Fixes #494. * [stack] Bump `sbv` pin [skip ci] * [stack] Bump resolver * Fix compile errors * [travis] Modify artefact paths * Fix Analysis pattern match checks. GHC 8.6's pattern match checker seems to have some bugs related to pattern synonyms (eg https://gitlab.haskell.org/ghc/ghc/issues/14253). We remove a few places where the `SObject` pattern synonym erroneously triggered a failure. We can also remove the `-fmax-pmcheck-iterations=5000` option. Tested via: ``` cabal clean; cabal test stack clean; stack test ``` * Remove unneeded sections from `cabal.project`
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GHC 8.6 is more strict that 8.4 regarding its analysis of incomplete pattern matches. I think this helps us more than it hinders us, as it lets us avoid foot-gun in the long term.
In the short term, this strictness causes warnings, and a few compilation errors. In particular, the following 4 locations in the test suites trigger errors involving missing
MonadFailinstances (arising from partial pattern matches):See #494 for a branch where the errors can easily be reproduced.
We can approach a solution in few ways:
hedgehogfixes all four issues (see also this issue for more info)The text was updated successfully, but these errors were encountered: