diff options
| -rw-r--r-- | src/compiler/scala/tools/nsc/settings/Warnings.scala | 13 | ||||
| -rw-r--r-- | src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala | 4 | ||||
| -rw-r--r-- | test/files/neg/t7623.check | 21 | ||||
| -rw-r--r-- | test/files/neg/t7623.flags | 1 | ||||
| -rw-r--r-- | test/files/neg/t7623.scala | 38 |
5 files changed, 71 insertions, 6 deletions
diff --git a/src/compiler/scala/tools/nsc/settings/Warnings.scala b/src/compiler/scala/tools/nsc/settings/Warnings.scala index d174dc86c7..41ce0837cb 100644 --- a/src/compiler/scala/tools/nsc/settings/Warnings.scala +++ b/src/compiler/scala/tools/nsc/settings/Warnings.scala @@ -28,10 +28,11 @@ trait Warnings { val warnUnusedImport = BooleanSetting("-Ywarn-unused-import", "Warn when imports are unused.") // Experimental lint warnings that are turned off, but which could be turned on programmatically. - // These warnings are said to blind those who dare enable them. - // They are not activated by -Xlint and can't be enabled on the command line. - val warnValueOverrides = { // Currently turned off as experimental. Created using constructor (new BS), so not available on the command line. - val flag = new BooleanSetting("value-overrides", "Generated value class method overrides an implementation") + // They are not activated by -Xlint and can't be enabled on the command line because they are not + // created using the standard factory methods. + + val warnValueOverrides = { + val flag = new BooleanSetting("value-overrides", "Generated value class method overrides an implementation.") flag.value = false flag } @@ -53,10 +54,11 @@ trait Warnings { val TypeParameterShadow = LintWarning("type-parameter-shadow", "A local type parameter shadows a type already in scope.") val PolyImplicitOverload = LintWarning("poly-implicit-overload", "Parameterized overloaded implicit methods are not visible as view bounds.") val OptionImplicit = LintWarning("option-implicit", "Option.apply used implicit view.") - val DelayedInitSelect = LintWarning("delayedinit-select", "Selecting member of DelayedInit") + val DelayedInitSelect = LintWarning("delayedinit-select", "Selecting member of DelayedInit.") val ByNameRightAssociative = LintWarning("by-name-right-associative", "By-name parameter of right associative operator.") val PackageObjectClasses = LintWarning("package-object-classes", "Class or object defined in package object.") val UnsoundMatch = LintWarning("unsound-match", "Pattern match may not be typesafe.") + val StarsAlign = LintWarning("stars-align", "Pattern sequence wildcard must align with sequence component.") def allLintWarnings = values.toSeq.asInstanceOf[Seq[LintWarning]] } @@ -77,6 +79,7 @@ trait Warnings { def warnByNameRightAssociative = lint contains ByNameRightAssociative def warnPackageObjectClasses = lint contains PackageObjectClasses def warnUnsoundMatch = lint contains UnsoundMatch + def warnStarsAlign = lint contains StarsAlign // Lint warnings that are currently -Y, but deprecated in that usage @deprecated("Use warnAdaptedArgs", since="2.11.2") diff --git a/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala b/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala index 8924394b72..2753baa51d 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala @@ -110,8 +110,10 @@ trait ScalacPatternExpanders { err("Star pattern must correspond with varargs or unapplySeq") else if (elementArity < 0) arityError("not enough") - else if (elementArity > 0 && !extractor.hasSeq) + else if (elementArity > 0 && !isSeq) arityError("too many") + else if (settings.warnStarsAlign && isSeq && productArity > 0 && (elementArity > 0 || !isStar)) + warn("A repeated case parameter or extracted sequence should be matched only by a sequence wildcard (_*).") aligned } diff --git a/test/files/neg/t7623.check b/test/files/neg/t7623.check new file mode 100644 index 0000000000..db368dd369 --- /dev/null +++ b/test/files/neg/t7623.check @@ -0,0 +1,21 @@ +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 should be matched only by a sequence wildcard (_*). + def g = "" match { case X(s, t) => } + ^ +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: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 @ _*) => } + ^ +error: No warnings can be incurred under -Xfatal-warnings. +6 warnings found +one error found diff --git a/test/files/neg/t7623.flags b/test/files/neg/t7623.flags new file mode 100644 index 0000000000..74c9e38323 --- /dev/null +++ b/test/files/neg/t7623.flags @@ -0,0 +1 @@ +-Xlint:stars-align -Xfatal-warnings diff --git a/test/files/neg/t7623.scala b/test/files/neg/t7623.scala new file mode 100644 index 0000000000..5c40f37bc1 --- /dev/null +++ b/test/files/neg/t7623.scala @@ -0,0 +1,38 @@ + + +case class C(s: String, xs: Int*) + +object X { def unapplySeq(a: Any): Option[(String, Seq[Int])] = Some("", List(1,2,3)) } + +// for case classes with varargs, avoid misaligned patterns +trait Ctest { + def f = C("") match { case C(s) => } + + def g = C("") match { case C(s, t) => } + + def h = C("") match { case C(s, t, u @ _*) => } + + def ok = C("") match { case C(s, u @ _*) => } +} +// for extractors that unapplySeq: Option[(Something, Seq[_])], avoid misaligned patterns +trait Xtest { + def f = "" match { case X(s) => } + + def g = "" match { case X(s, t) => } + + def h = "" match { case X(s, t, u @ _*) => } + + def ok = "" match { case X(s, u @ _*) => } +} +// for extractors that unapplySeq: Option[Seq[_]], anything goes +trait Rtest { + val r = "(a+)".r + + def f = "" match { case r(s) => } + + def g = "" match { case r(s, t) => } + + def h = "" match { case r(s, t, u @ _*) => } + + def whatever = "" match { case r(u @ _*) => } +} |