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| author | Eugene Burmako <xeno.by@gmail.com> | 2013-10-02 17:22:17 +0200 |
|---|---|---|
| committer | Adriaan Moors <adriaan.moors@typesafe.com> | 2013-11-12 18:40:02 -0800 |
| commit | f83296552aa80faf8a9350131c0448bc05b34c96 (patch) | |
| tree | 181a29f647609ba4d9cd8566fcde96c603d61259 | |
| parent | 0d5c2f76ea30c6a45471dac635f035e931075453 (diff) | |
| download | scala-f83296552aa80faf8a9350131c0448bc05b34c96.tar.gz scala-f83296552aa80faf8a9350131c0448bc05b34c96.tar.bz2 scala-f83296552aa80faf8a9350131c0448bc05b34c96.zip | |
blackbox restriction #4: can't customize pattern matching
When an application of a blackbox macro is used as an extractor in a
pattern match, it triggers an unconditional compiler error,
preventing customizations of pattern matching implemented with macros.
8 files changed, 62 insertions, 4 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala b/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala index f69b8a9697..ba135d7d25 100644 --- a/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala @@ -409,9 +409,10 @@ trait PatternTypers { if (fun1.tpe.isErroneous) duplErrTree - else if (unapplyMethod.isMacro && !fun1.isInstanceOf[Apply]) - duplErrorTree(WrongShapeExtractorExpansion(tree)) - else + else if (unapplyMethod.isMacro && !fun1.isInstanceOf[Apply]) { + if (isBlackbox(unapplyMethod)) duplErrorTree(BlackboxExtractorExpansion(tree)) + else duplErrorTree(WrongShapeExtractorExpansion(tree)) + } else makeTypedUnApply() } diff --git a/test/files/neg/macro-blackbox-extractor.check b/test/files/neg/macro-blackbox-extractor.check new file mode 100644 index 0000000000..4c53ff19b8 --- /dev/null +++ b/test/files/neg/macro-blackbox-extractor.check @@ -0,0 +1,4 @@ +Test_2.scala:3: error: extractor macros can only be whitebox + case Extractor(x) => println(x) + ^ +one error found diff --git a/test/files/neg/macro-blackbox-extractor/Macros_1.scala b/test/files/neg/macro-blackbox-extractor/Macros_1.scala new file mode 100644 index 0000000000..5c7748bec9 --- /dev/null +++ b/test/files/neg/macro-blackbox-extractor/Macros_1.scala @@ -0,0 +1,21 @@ +import scala.reflect.macros.BlackboxContext +import language.experimental.macros + +object Extractor { + def unapply(x: Int) = macro Macros.unapplyImpl +} + +object Macros { + def unapplyImpl(c: BlackboxContext)(x: c.Tree) = { + import c.universe._ + q""" + new { + class Match(x: Int) { + def isEmpty = false + def get = x + } + def unapply(x: Int) = new Match(x) + }.unapply($x) + """ + } +} diff --git a/test/files/neg/macro-blackbox-extractor/Test_2.scala b/test/files/neg/macro-blackbox-extractor/Test_2.scala new file mode 100644 index 0000000000..41be6f9767 --- /dev/null +++ b/test/files/neg/macro-blackbox-extractor/Test_2.scala @@ -0,0 +1,5 @@ +object Test extends App { + 42 match { + case Extractor(x) => println(x) + } +} diff --git a/test/files/neg/t5903d.check b/test/files/neg/t5903d.check index 9b8526b7f5..54a91a7ba6 100644 --- a/test/files/neg/t5903d.check +++ b/test/files/neg/t5903d.check @@ -1,4 +1,4 @@ -Test_2.scala:4: error: extractor macros can only expand into extractor calls +Test_2.scala:4: error: extractor macros can only be whitebox case t"$x" => println(x) ^ one error found diff --git a/test/files/run/macro-whitebox-extractor.check b/test/files/run/macro-whitebox-extractor.check new file mode 100644 index 0000000000..d81cc0710e --- /dev/null +++ b/test/files/run/macro-whitebox-extractor.check @@ -0,0 +1 @@ +42 diff --git a/test/files/run/macro-whitebox-extractor/Macros_1.scala b/test/files/run/macro-whitebox-extractor/Macros_1.scala new file mode 100644 index 0000000000..4a1138fc9d --- /dev/null +++ b/test/files/run/macro-whitebox-extractor/Macros_1.scala @@ -0,0 +1,21 @@ +import scala.reflect.macros.WhiteboxContext +import language.experimental.macros + +object Extractor { + def unapply(x: Int) = macro Macros.unapplyImpl +} + +object Macros { + def unapplyImpl(c: WhiteboxContext)(x: c.Tree) = { + import c.universe._ + q""" + new { + class Match(x: Int) { + def isEmpty = false + def get = x + } + def unapply(x: Int) = new Match(x) + }.unapply($x) + """ + } +} diff --git a/test/files/run/macro-whitebox-extractor/Test_2.scala b/test/files/run/macro-whitebox-extractor/Test_2.scala new file mode 100644 index 0000000000..41be6f9767 --- /dev/null +++ b/test/files/run/macro-whitebox-extractor/Test_2.scala @@ -0,0 +1,5 @@ +object Test extends App { + 42 match { + case Extractor(x) => println(x) + } +} |