Add tests

Author: odersky

compiler/src/dotty/tools/dotc/ast/Desugar.scala

@@ -203,13 +203,7 @@ object desugar {
    *      def f$default$1[T] = 1
    *      def f$default$2[T](x: Int) = x + "m"
    *
-   *  3. Convert <: T to : T in specializing inline methods. E.g.
-   *
-   *      inline def f(x: Boolean) <: Any = if (x) 1 else ""
-   *  ==>
-   *      inline def f(x: Boolean): Any = if (x) 1 else ""
-   *
-   *  4. Upcast non-specializing inline methods. E.g.
+   *  3. Upcast non-specializing inline methods. E.g.
    *
    *      inline def f(x: Boolean): Any = if (x) 1 else ""
    *  ==>

tests/neg/specializing-inline.scala

@@ -2,7 +2,7 @@ object Test {
 
   inline def h(x: Boolean) = if (x) 1 else ""
   val z = h(true)
-  val zc: Int = z
+  val zc: Int = z // error
 
   inline def g <: Any = 1
   val y = g

tests/neg/transparent-inline.scala

@@ -0,0 +1,37 @@
+transparent def bar: Any = 2  // error: transparent can be used only with inline
+
+object test1:
+
+  def x: Int = baz(true) // error: type mismatch
+  inline def baz(x: Boolean): Any =
+    if x then 1 else ""
+  inline def bam(x: Boolean): Any =
+    if x then 1 else ""
+  def y: Int = bam(true) // error: type mismatch
+
+object test2:
+
+  def x: 1 = baz(true) // OK
+  transparent inline def baz(x: Boolean) =
+    if x then 1 else ""
+  transparent inline def bam(x: Boolean) =
+    if x then 1 else ""
+  def y: 1 = bam(true) // OK
+
+object test3:
+
+  def x: Int = baz(true) // error: type mismatch
+  inline def baz(x: Boolean) =
+    if x then 1 else ""
+  inline def bam(x: Boolean) =
+    if x then 1 else ""
+  def y: Int = bam(true) // error: type mismatch
+
+object test4:
+
+  def x: 1 = baz(true) // OK
+  transparent inline def baz(x: Boolean): Any =
+    if x then 1 else ""
+  transparent inline def bam(x: Boolean): Any =
+    if x then 1 else ""
+  def y: 1 = bam(true) // OK

tests/pos/transparent-inline.scala

@@ -0,0 +1,4 @@
+inline def foo: Any = 1
+inline transparent def bar: Any = 2
+val x: 2 = bar
+