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| author | Matthew Pickering <matthewtpickering@gmail.com> | 2022-12-01 17:43:40 +0000 |
|---|---|---|
| committer | Zubin Duggal <zubin.duggal@gmail.com> | 2023-02-07 18:47:09 +0530 |
| commit | 52e579b610ba3fe59a56596c88b560f3659bd73f (patch) | |
| tree | 0a7524f22186c259185340729b378f594aa946fd | |
| parent | a090f5c3d4376810617237ff5be589fafc0d96b6 (diff) | |
| download | haskell-52e579b610ba3fe59a56596c88b560f3659bd73f.tar.gz | |
ApplicativeDo: Set pattern location before running exhaustiveness checker
This improves the error messages of the exhaustiveness checker when
checking statements which have been moved around with ApplicativeDo.
Before:
Test.hs:2:3: warning: [GHC-62161] [-Wincomplete-uni-patterns]
Pattern match(es) are non-exhaustive
In a pattern binding:
Patterns of type ‘Maybe ()’ not matched: Nothing
|
2 | let x = ()
| ^^^^^^^^^^
After:
Test.hs:4:3: warning: [GHC-62161] [-Wincomplete-uni-patterns]
Pattern match(es) are non-exhaustive
In a pattern binding:
Patterns of type ‘Maybe ()’ not matched: Nothing
|
4 | ~(Just res1) <- seq x (pure $ Nothing @())
|
Fixes #22483
(cherry picked from commit 74c767df770766d8d52e87b9ff7da10f94620a91)
(cherry picked from commit 51c6051bcc405bc1dbddd450ade949acd70db6b8)
| -rw-r--r-- | compiler/GHC/HsToCore/Expr.hs | 3 | ||||
| -rw-r--r-- | testsuite/tests/ado/T22483.hs | 7 | ||||
| -rw-r--r-- | testsuite/tests/ado/T22483.stderr | 8 | ||||
| -rw-r--r-- | testsuite/tests/ado/all.T | 1 |
4 files changed, 18 insertions, 1 deletions
diff --git a/compiler/GHC/HsToCore/Expr.hs b/compiler/GHC/HsToCore/Expr.hs index 9ce903286d..b6fe849e14 100644 --- a/compiler/GHC/HsToCore/Expr.hs +++ b/compiler/GHC/HsToCore/Expr.hs @@ -984,7 +984,8 @@ dsDo ctx stmts ; body' <- dsLExpr $ noLocA $ HsDo body_ty ctx (noLocA stmts) ; let match_args (pat, fail_op) (vs,body) - = do { var <- selectSimpleMatchVarL Many pat + = putSrcSpanDs (getLocA pat) $ + do { var <- selectSimpleMatchVarL Many pat ; match <- matchSinglePatVar var Nothing (StmtCtxt ctx) pat body_ty (cantFailMatchResult body) ; match_code <- dsHandleMonadicFailure ctx pat match fail_op diff --git a/testsuite/tests/ado/T22483.hs b/testsuite/tests/ado/T22483.hs new file mode 100644 index 0000000000..31d2f72add --- /dev/null +++ b/testsuite/tests/ado/T22483.hs @@ -0,0 +1,7 @@ +main = do + let x = () + res2 <- pure () + ~(Just res1) <- seq x (pure $ Nothing @()) + print res1 + print res2 + pure () diff --git a/testsuite/tests/ado/T22483.stderr b/testsuite/tests/ado/T22483.stderr new file mode 100644 index 0000000000..7aa274a992 --- /dev/null +++ b/testsuite/tests/ado/T22483.stderr @@ -0,0 +1,8 @@ + +T22483.hs:1:1: warning: [-Wmissing-signatures (in -Wall)] + Top-level binding with no type signature: main :: IO () + +T22483.hs:4:3: warning: [-Wincomplete-uni-patterns (in -Wall)] + Pattern match(es) are non-exhaustive + In a pattern binding: + Patterns of type ‘Maybe ()’ not matched: Nothing diff --git a/testsuite/tests/ado/all.T b/testsuite/tests/ado/all.T index 8c07539965..58e8c26a81 100644 --- a/testsuite/tests/ado/all.T +++ b/testsuite/tests/ado/all.T @@ -18,3 +18,4 @@ test('T14163', normal, compile_and_run, ['']) test('T15344', normal, compile_and_run, ['']) test('T16628', normal, compile_fail, ['']) test('T17835', normal, compile, ['']) +test('T22483', normal, compile, ['-Wall']) |