From 79436caa98ba46de644841a67ea9ff103831e574 Mon Sep 17 00:00:00 2001 From: Som Snytt Date: Wed, 3 Jun 2015 16:36:43 -0700 Subject: SI-9343 Xlint less strict on pattern sequences -Xlint:stars-align warns only if elementarity > 0, that is, if an extracted sequence is not matched entirely by a pattern sequence, that is, in SLS 8.1.9 on pattern sequences, n = 1 and that pattern is a pattern sequence. This is still only triggered if productarity > 0, that is, a non-pattern-sequence pattern is required for the match. This is a sensitive area because it borders on exhaustiveness checking: it would be preferable to verify just that the match is exhaustive, and to emit this warning only if it is not. --- test/files/neg/t7623.check | 24 +++++++++--------------- test/files/neg/t7623.scala | 8 ++++---- 2 files changed, 13 insertions(+), 19 deletions(-) (limited to 'test/files') diff --git a/test/files/neg/t7623.check b/test/files/neg/t7623.check index db368dd369..de35023664 100644 --- a/test/files/neg/t7623.check +++ b/test/files/neg/t7623.check @@ -1,21 +1,15 @@ -t7623.scala:19: warning: A repeated case parameter or extracted sequence should be matched only by a sequence wildcard (_*). - def f = "" match { case X(s) => } +t7623.scala:21: warning: A repeated case parameter or extracted sequence is not matched by a sequence wildcard (_*), and may fail at runtime. + def g = "" match { case X(s, t) => } // warn ^ -t7623.scala:21: warning: A repeated case parameter or extracted sequence should be matched only by a sequence wildcard (_*). - def g = "" match { case X(s, t) => } +t7623.scala:23: warning: Sequence wildcard (_*) does not align with repeated case parameter or extracted sequence; the result may be unexpected. + def h = "" match { case X(s, t, u @ _*) => } // warn ^ -t7623.scala:23: warning: A repeated case parameter or extracted sequence should be matched only by a sequence wildcard (_*). - def h = "" match { case X(s, t, u @ _*) => } - ^ -t7623.scala:9: warning: A repeated case parameter or extracted sequence should be matched only by a sequence wildcard (_*). - def f = C("") match { case C(s) => } - ^ -t7623.scala:11: warning: A repeated case parameter or extracted sequence should be matched only by a sequence wildcard (_*). - def g = C("") match { case C(s, t) => } +t7623.scala:11: warning: A repeated case parameter or extracted sequence is not matched by a sequence wildcard (_*), and may fail at runtime. + def g = C("") match { case C(s, t) => } // warn ^ -t7623.scala:13: warning: A repeated case parameter or extracted sequence should be matched only by a sequence wildcard (_*). - def h = C("") match { case C(s, t, u @ _*) => } +t7623.scala:13: warning: Sequence wildcard (_*) does not align with repeated case parameter or extracted sequence; the result may be unexpected. + def h = C("") match { case C(s, t, u @ _*) => } // warn ^ error: No warnings can be incurred under -Xfatal-warnings. -6 warnings found +four warnings found one error found diff --git a/test/files/neg/t7623.scala b/test/files/neg/t7623.scala index 5c40f37bc1..5334cc5f69 100644 --- a/test/files/neg/t7623.scala +++ b/test/files/neg/t7623.scala @@ -8,9 +8,9 @@ object X { def unapplySeq(a: Any): Option[(String, Seq[Int])] = Some("", List(1, trait Ctest { def f = C("") match { case C(s) => } - def g = C("") match { case C(s, t) => } + def g = C("") match { case C(s, t) => } // warn - def h = C("") match { case C(s, t, u @ _*) => } + def h = C("") match { case C(s, t, u @ _*) => } // warn def ok = C("") match { case C(s, u @ _*) => } } @@ -18,9 +18,9 @@ trait Ctest { trait Xtest { def f = "" match { case X(s) => } - def g = "" match { case X(s, t) => } + def g = "" match { case X(s, t) => } // warn - def h = "" match { case X(s, t, u @ _*) => } + def h = "" match { case X(s, t, u @ _*) => } // warn def ok = "" match { case X(s, u @ _*) => } } -- cgit v1.2.3