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author | Jason Zaugg <jzaugg@gmail.com> | 2013-04-17 09:19:21 +0200 |
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committer | Jason Zaugg <jzaugg@gmail.com> | 2013-04-17 13:05:08 +0200 |
commit | 15e9ef8f083e0c0dc75bf51a0784f56df2e2bea8 (patch) | |
tree | 4ace5c078ce2931263b5de50de77377faa3da778 /test/files | |
parent | 4525e9223a2fb7c1ec3014073566b559e5839805 (diff) | |
download | scala-15e9ef8f083e0c0dc75bf51a0784f56df2e2bea8.tar.gz scala-15e9ef8f083e0c0dc75bf51a0784f56df2e2bea8.tar.bz2 scala-15e9ef8f083e0c0dc75bf51a0784f56df2e2bea8.zip |
SI-7377 Fix retypechecking of patterns on case companion alias
Some ancient code in Typers switches from PATTERNmode to
EXPRmode when encountering `stableF(...)`. It just
typechecks `stableF` and discards the arguments.
To the best of Martin's recollection, this has something
to do with the need to typecheck patterns rather late in
the compiler, after `a.b` had been translated to `a.b()`
in `Uncurry`. I'm not able to motivate this with tests
using `-Xoldpatmat`; was there ever an even older pattern
matcher that ran *after* uncurry?
What changed in 2.10.1 to expose this wrinkle? dfbaaa17
fixed `TypeTree.copyAttrs` to copy the original tree.
During the descent of `ResetAttrs`, sub-trees are duplicated
before begin further transformed. Duplicating the `Match`
in 2.10.0 would forget that the original tree of:
pat = (a: Int)Foo(_)
`----------`
`- TypeTree((a: Int)Foo), with original Select(..., "FooAlias")
The retypechecking would operate on the `MethodType`, rather
than the `Select`, which was not considered a stable
application.
For 2.10.x, I've just tightened up the condition to only
hit this if `args` is empty. I'm almost certain that the code
can be removed altogether, and I'll do that when this is merged
to master.
Diffstat (limited to 'test/files')
-rw-r--r-- | test/files/pos/t7377/Client_2.scala | 11 | ||||
-rw-r--r-- | test/files/pos/t7377/Macro_1.scala | 7 | ||||
-rw-r--r-- | test/files/pos/t7377b.flags | 1 | ||||
-rw-r--r-- | test/files/pos/t7377b.scala | 13 |
4 files changed, 32 insertions, 0 deletions
diff --git a/test/files/pos/t7377/Client_2.scala b/test/files/pos/t7377/Client_2.scala new file mode 100644 index 0000000000..5728956cca --- /dev/null +++ b/test/files/pos/t7377/Client_2.scala @@ -0,0 +1,11 @@ +object Test { + M.noop(List(1) match { case Nil => 0; case (x::xs) => x }) + + case class Foo(a: Int) + val FooAlias: Foo.type = Foo + M.noop(Foo(0) match { case FooAlias(_) => 0 }) + + case class Bar() + val BarAlias: Bar.type = Bar + M.noop(Bar() match { case BarAlias() => 0 }) +} diff --git a/test/files/pos/t7377/Macro_1.scala b/test/files/pos/t7377/Macro_1.scala new file mode 100644 index 0000000000..a0ec1d84af --- /dev/null +++ b/test/files/pos/t7377/Macro_1.scala @@ -0,0 +1,7 @@ +import language.experimental._ +import reflect.macros.Context + +object M { + def noopImpl[A](c: Context)(expr: c.Expr[A]): c.Expr[A] = c.Expr(c.typeCheck(c.resetLocalAttrs(expr.tree))) + def noop[A](expr: A): A = macro noopImpl[A] +} diff --git a/test/files/pos/t7377b.flags b/test/files/pos/t7377b.flags new file mode 100644 index 0000000000..cb8324a345 --- /dev/null +++ b/test/files/pos/t7377b.flags @@ -0,0 +1 @@ +-Xoldpatmat
\ No newline at end of file diff --git a/test/files/pos/t7377b.scala b/test/files/pos/t7377b.scala new file mode 100644 index 0000000000..aeee800d57 --- /dev/null +++ b/test/files/pos/t7377b.scala @@ -0,0 +1,13 @@ +object Test { + List(1) match { case Nil => 0; case (x::xs) => x } + + case class Foo(a: Int) + val FooAlias: Foo.type = Foo + Foo(0) match { case FooAlias(_) => 0 } + Foo(0) match { case Foo(_) => 0 } + + case class Bar() + val BarAlias: Bar.type = Bar + Bar() match { case BarAlias() => 0 } + Bar() match { case Bar() => 0 } +} |