From a87d40960bfdb4a683c05d3430a8874cb4dcff36 Mon Sep 17 00:00:00 2001 From: Jason Zaugg Date: Sun, 13 Jan 2013 17:42:48 +0100 Subject: SI-6968 Simple Tuple patterns aren't irrefutable Reverts part of c82ecab. The parser can't assume that a pattern `(a, b)` will match, as results of `.isInstanceOf[Tuple2]` can't be statically known until after the typer. The reopens SI-1336, SI-5589 and SI-4574, in exchange for fixing this regression SI-6968. Keeping all of those fixed will require a better definition of irrefutability, and some acrobatics to ensure safe passage to the ambiguous trees through typechecking. --- test/pending/neg/t5589neg.check | 37 +++++++++++++++++++++++++++++++++++++ test/pending/neg/t5589neg.scala | 6 ++++++ test/pending/neg/t5589neg2.scala | 13 +++++++++++++ test/pending/pos/t1336.scala | 10 ++++++++++ test/pending/pos/t5589.scala | 22 ++++++++++++++++++++++ test/pending/run/t4574.scala | 13 +++++++++++++ 6 files changed, 101 insertions(+) create mode 100644 test/pending/neg/t5589neg.check create mode 100644 test/pending/neg/t5589neg.scala create mode 100644 test/pending/neg/t5589neg2.scala create mode 100644 test/pending/pos/t1336.scala create mode 100644 test/pending/pos/t5589.scala create mode 100644 test/pending/run/t4574.scala (limited to 'test/pending') diff --git a/test/pending/neg/t5589neg.check b/test/pending/neg/t5589neg.check new file mode 100644 index 0000000000..f1dad94df3 --- /dev/null +++ b/test/pending/neg/t5589neg.check @@ -0,0 +1,37 @@ +t5589neg.scala:2: warning: `withFilter' method does not yet exist on scala.util.Either.RightProjection[Int,String], using `filter' method instead + def f5(x: Either[Int, String]) = for ((y1, y2: String) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:2: error: constructor cannot be instantiated to expected type; + found : (T1, T2) + required: String + def f5(x: Either[Int, String]) = for ((y1, y2: String) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:3: warning: `withFilter' method does not yet exist on scala.util.Either.RightProjection[Int,String], using `filter' method instead + def f6(x: Either[Int, String]) = for ((y1, y2: Any) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:3: error: constructor cannot be instantiated to expected type; + found : (T1, T2) + required: String + def f6(x: Either[Int, String]) = for ((y1, y2: Any) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:4: error: constructor cannot be instantiated to expected type; + found : (T1,) + required: (String, Int) + def f7(x: Either[Int, (String, Int)]) = for (y1 @ Tuple1(y2) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:4: error: not found: value y2 + def f7(x: Either[Int, (String, Int)]) = for (y1 @ Tuple1(y2) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:5: error: constructor cannot be instantiated to expected type; + found : (T1, T2, T3) + required: (String, Int) + def f8(x: Either[Int, (String, Int)]) = for ((y1, y2, y3) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:5: error: not found: value y1 + def f8(x: Either[Int, (String, Int)]) = for ((y1, y2, y3) <- x.right) yield ((y1, y2)) + ^ +t5589neg.scala:5: error: not found: value y2 + def f8(x: Either[Int, (String, Int)]) = for ((y1, y2, y3) <- x.right) yield ((y1, y2)) + ^ +two warnings found +7 errors found diff --git a/test/pending/neg/t5589neg.scala b/test/pending/neg/t5589neg.scala new file mode 100644 index 0000000000..31ff2c3693 --- /dev/null +++ b/test/pending/neg/t5589neg.scala @@ -0,0 +1,6 @@ +class A { + def f5(x: Either[Int, String]) = for ((y1, y2: String) <- x.right) yield ((y1, y2)) + def f6(x: Either[Int, String]) = for ((y1, y2: Any) <- x.right) yield ((y1, y2)) + def f7(x: Either[Int, (String, Int)]) = for (y1 @ Tuple1(y2) <- x.right) yield ((y1, y2)) + def f8(x: Either[Int, (String, Int)]) = for ((y1, y2, y3) <- x.right) yield ((y1, y2)) +} diff --git a/test/pending/neg/t5589neg2.scala b/test/pending/neg/t5589neg2.scala new file mode 100644 index 0000000000..b7c7ab7218 --- /dev/null +++ b/test/pending/neg/t5589neg2.scala @@ -0,0 +1,13 @@ +class A { + def f1(x: List[((((Int, (Double, (Float, String))), List[String]), List[Int]), List[Float])]) = { + for (((((a, (b, (c, d))), es), fs), gs) <- x) yield (d :: es).mkString(", ") // ok + } + + def f2(x: List[((((Int, (Double, (Float, String))), List[String]), List[Int]), List[Float])]) = { + for (((((a, (b, (c, (d1, d2)))), es), fs), gs) <- x) yield (d :: es).mkString(", ") // not ok + } + + def f3(x: List[((((Int, (Double, (Float, String))), List[String]), List[Int]), List[Float])]) = { + for (((((a, (b, _)), es), fs), gs) <- x) yield (es ::: fs).mkString(", ") // ok + } +} \ No newline at end of file diff --git a/test/pending/pos/t1336.scala b/test/pending/pos/t1336.scala new file mode 100644 index 0000000000..63967985c7 --- /dev/null +++ b/test/pending/pos/t1336.scala @@ -0,0 +1,10 @@ +object Foo { + def foreach( f : ((Int,Int)) => Unit ) { + println("foreach") + f(1,2) + } + + for( (a,b) <- this ) { + println((a,b)) + } +} diff --git a/test/pending/pos/t5589.scala b/test/pending/pos/t5589.scala new file mode 100644 index 0000000000..69cbb20391 --- /dev/null +++ b/test/pending/pos/t5589.scala @@ -0,0 +1,22 @@ +class A { + // First three compile. + def f1(x: Either[Int, String]) = x.right map (y => y) + def f2(x: Either[Int, String]) = for (y <- x.right) yield y + def f3(x: Either[Int, (String, Int)]) = x.right map { case (y1, y2) => (y1, y2) } + // Last one fails. + def f4(x: Either[Int, (String, Int)]) = for ((y1, y2) <- x.right) yield ((y1, y2)) +/** +./a.scala:5: error: constructor cannot be instantiated to expected type; + found : (T1, T2) + required: Either[Nothing,(String, Int)] + def f4(x: Either[Int, (String, Int)]) = for ((y1, y2) <- x.right) yield ((y1, y2)) + ^ +./a.scala:5: error: not found: value y1 + def f4(x: Either[Int, (String, Int)]) = for ((y1, y2) <- x.right) yield ((y1, y2)) + ^ +./a.scala:5: error: not found: value y2 + def f4(x: Either[Int, (String, Int)]) = for ((y1, y2) <- x.right) yield ((y1, y2)) + ^ +three errors found +**/ +} diff --git a/test/pending/run/t4574.scala b/test/pending/run/t4574.scala new file mode 100644 index 0000000000..1dde496aca --- /dev/null +++ b/test/pending/run/t4574.scala @@ -0,0 +1,13 @@ +object Test { + val xs: List[(Int, Int)] = List((2, 2), null) + + def expectMatchError[T](msg: String)(body: => T) { + try { body ; assert(false, "Should not succeed.") } + catch { case _: MatchError => println(msg) } + } + + def main(args: Array[String]): Unit = { + expectMatchError("I hereby refute null!")( for ((x, y) <- xs) yield x ) + expectMatchError("I denounce null as unListLike!")( (null: Any) match { case List(_*) => true } ) + } +} -- cgit v1.2.3