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Diffstat (limited to 'src')
-rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/SyntheticMethods.scala | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/SyntheticMethods.scala b/src/compiler/scala/tools/nsc/typechecker/SyntheticMethods.scala index 17e67e6429..a907ab6c66 100644 --- a/src/compiler/scala/tools/nsc/typechecker/SyntheticMethods.scala +++ b/src/compiler/scala/tools/nsc/typechecker/SyntheticMethods.scala @@ -157,11 +157,23 @@ trait SyntheticMethods extends ast.TreeDSL { Ident(m.firstParam) IS_OBJ classExistentialType(clazz)) } - /** (that.isInstanceOf[this.C]) - * where that is the given methods first parameter. + /** that match { case _: this.C => true ; case _ => false } + * where `that` is the given method's first parameter. + * + * An isInstanceOf test is insufficient because it has weaker + * requirements than a pattern match. Given an inner class Foo and + * two different instantiations of the container, an x.Foo and and a y.Foo + * are both .isInstanceOf[Foo], but the one does not match as the other. */ - def thatTest(eqmeth: Symbol): Tree = - gen.mkIsInstanceOf(Ident(eqmeth.firstParam), classExistentialType(clazz), true, false) + def thatTest(eqmeth: Symbol): Tree = { + Match( + Ident(eqmeth.firstParam), + List( + CaseDef(Typed(Ident(nme.WILDCARD), TypeTree(clazz.tpe)), EmptyTree, TRUE), + CaseDef(WILD.empty, EmptyTree, FALSE) + ) + ) + } /** (that.asInstanceOf[this.C]) * where that is the given methods first parameter. |