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author | Eugene Burmako <xeno.by@gmail.com> | 2014-01-19 23:00:09 +0300 |
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committer | Eugene Burmako <xeno.by@gmail.com> | 2014-01-20 09:48:12 +0300 |
commit | 936d60a2621088ba463a44c2f2d6450986022169 (patch) | |
tree | 4137839890784150dfc2f18c308ed1ae33a10a42 | |
parent | 6a6b485fe98890f73a03753e3981be5fa580ed02 (diff) | |
download | scala-936d60a2621088ba463a44c2f2d6450986022169.tar.gz scala-936d60a2621088ba463a44c2f2d6450986022169.tar.bz2 scala-936d60a2621088ba463a44c2f2d6450986022169.zip |
SI-8158 compiler hangs printing out fancy types
Apparently, even though the compiler has safeguards against infinite type
printouts, having a depth counter, we didn’t account for the cases when
printouts are both self-referential and self-multiplying.
For one, SI-8158 provides an example of such a type, which is a structural
type that refers to itself twice in return types of its methods. At first,
printing such a type would go deeper and deeper, but then it will hit
the depth limit and start multiply indefinitely.
This commit fixes this particular problem by recognizing self-references
as this.type’s and printing them out as such. The subsequent commit will
introduce a more general facility.
-rw-r--r-- | src/reflect/scala/reflect/internal/Symbols.scala | 13 | ||||
-rw-r--r-- | test/files/neg/t8158.check | 4 | ||||
-rw-r--r-- | test/files/neg/t8158/Macros_1.scala | 34 | ||||
-rw-r--r-- | test/files/neg/t8158/Test_2.scala | 14 | ||||
-rw-r--r-- | test/files/run/t5256h.check | 2 |
5 files changed, 62 insertions, 5 deletions
diff --git a/src/reflect/scala/reflect/internal/Symbols.scala b/src/reflect/scala/reflect/internal/Symbols.scala index c2689fe7e9..54e5b2781e 100644 --- a/src/reflect/scala/reflect/internal/Symbols.scala +++ b/src/reflect/scala/reflect/internal/Symbols.scala @@ -2519,6 +2519,10 @@ trait Symbols extends api.Symbols { self: SymbolTable => if (settings.debug.value) parentsString(tp.parents) else briefParentsString(tp.parents) ) + def isStructuralThisType = ( + // prevents disasters like SI-8158 + owner.isInitialized && owner.isStructuralRefinement && tp == owner.tpe + ) if (isType) typeParamsString(tp) + ( if (isClass) " extends " + parents else if (isAliasType) " = " + tp.resultType @@ -2529,10 +2533,11 @@ trait Symbols extends api.Symbols { self: SymbolTable => ) else if (isModule) "" // avoid "object X of type X.type" else tp match { - case PolyType(tparams, res) => typeParamsString(tp) + infoString(res) - case NullaryMethodType(res) => infoString(res) - case MethodType(params, res) => valueParamsString(tp) + infoString(res) - case _ => ": " + tp + case PolyType(tparams, res) => typeParamsString(tp) + infoString(res) + case NullaryMethodType(res) => infoString(res) + case MethodType(params, res) => valueParamsString(tp) + infoString(res) + case _ if isStructuralThisType => ": this.type" + case _ => ": " + tp } } diff --git a/test/files/neg/t8158.check b/test/files/neg/t8158.check new file mode 100644 index 0000000000..aaa62ddea4 --- /dev/null +++ b/test/files/neg/t8158.check @@ -0,0 +1,4 @@ +Test_2.scala:10: error: not enough patterns for <$anon: AnyRef> offering AnyRef{def isEmpty: Boolean; def get: this.type; def unapply(x: String): this.type}: expected 1, found 0 + case X() => + ^ +one error found diff --git a/test/files/neg/t8158/Macros_1.scala b/test/files/neg/t8158/Macros_1.scala new file mode 100644 index 0000000000..b84e3ed8d3 --- /dev/null +++ b/test/files/neg/t8158/Macros_1.scala @@ -0,0 +1,34 @@ +import scala.language.experimental.macros +import scala.reflect.macros.whitebox.Context + +object Max { + def impl(c: Context)(any: c.Expr[Any]): c.Expr[Any] = { + import c.universe._ + def fail(msg: String) = c.abort(c.enclosingPosition, msg) + val t = c.macroApplication match { + case q"$_.unapply($unargs)" => + /* hangs + */ + q""" + new { + def isEmpty = false + def get = this + def unapply(x: String) = this + }.unapply($unargs) + """ + /* + if get returns Unit or Boolean: + wrong number of patterns for <$anon: AnyRef> offering Unit: expected 1, found 0 + */ + /* straightforward + q""" + new { + def unapply(x: String) = true + }.unapply($unargs) + """ + */ + case _ => fail("bad appl") + } + c.Expr[Any](t) + } +}
\ No newline at end of file diff --git a/test/files/neg/t8158/Test_2.scala b/test/files/neg/t8158/Test_2.scala new file mode 100644 index 0000000000..f5ac6616bb --- /dev/null +++ b/test/files/neg/t8158/Test_2.scala @@ -0,0 +1,14 @@ +import scala.language.experimental.macros + +object X { + def unapply(any: Any): Any = macro Max.impl +} + +class BugTest { + def bug(): Unit = { + "any" match { + case X() => + case _ => ??? + } + } +}
\ No newline at end of file diff --git a/test/files/run/t5256h.check b/test/files/run/t5256h.check index 1a4a92a684..300a40f653 100644 --- a/test/files/run/t5256h.check +++ b/test/files/run/t5256h.check @@ -3,5 +3,5 @@ Test.$anon$1 java.lang.Object { final private val x: Int def x(): Int - def <init>(): java.lang.Object{def x(): Int} + def <init>(): this.type } |