SI-6061 adds weakly conformance for number types to resolveOverloaded

This fix changes resolveOverloaded in scala.reflect.internal
so that numeric widening on the actual argument types is also
considered for primitive number types. Needs changes in functions
applicable and mostSpecific.

3 files changed, 35 insertions, 14 deletions

diff --git a/src/reflect/scala/reflect/internal/Symbols.scala b/src/reflect/scala/reflect/internal/Symbols.scala
index 77c27126c5..47e84b4918 100644
--- a/src/reflect/scala/reflect/internal/Symbols.scala
+++ b/src/reflect/scala/reflect/internal/Symbols.scala
@@ -93,6 +93,16 @@ trait Symbols extends api.Symbols { self: SymbolTable =>
 
       // Begin Correlation Helpers
 
+      def weaklyConforms(a: Type, f: Type): Boolean = (a =:= f) || {
+        if(a =:= typeOf[Byte]) weaklyConforms(typeOf[Short], f)
+        else if(a =:= typeOf[Short]) weaklyConforms(typeOf[Int], f)
+        else if(a =:= typeOf[Char]) weaklyConforms(typeOf[Int], f)
+        else if(a =:= typeOf[Int]) weaklyConforms(typeOf[Long], f)
+        else if(a =:= typeOf[Long]) weaklyConforms(typeOf[Float], f)
+        else if(a =:= typeOf[Float]) weaklyConforms(typeOf[Double], f)
+        else false
+      }
+
       def isCompatible(tp: Type, pt: Type): Boolean = {
         def isCompatibleByName(tp: Type, pt: Type): Boolean = pt match {
           case TypeRef(_, ByNameParamClass, List(res)) if !definitions.isByNameParamType(tp) =>
@@ -100,13 +110,13 @@ trait Symbols extends api.Symbols { self: SymbolTable =>
           case _ =>
             false
         }
-        (tp <:< pt) || isCompatibleByName(tp, pt)
+        (tp <:< pt) || weaklyConforms(tp, pt) || isCompatibleByName(tp, pt)
       }
 
       def signatureAsSpecific(method1: MethodSymbol, method2: MethodSymbol): Boolean = {
         (substituteTypeParams(method1), substituteTypeParams(method2)) match {
           case (NullaryMethodType(r1), NullaryMethodType(r2)) =>
-            r1 <:< r2
+            r1 <:< r2 || weaklyConforms(r1, r2)
           case (NullaryMethodType(_), MethodType(_, _)) =>
             true
           case (MethodType(_, _), NullaryMethodType(_)) =>
@@ -298,7 +308,7 @@ trait Symbols extends api.Symbols { self: SymbolTable =>
           else {
             val a = argTypes
             val p = extend(paramTypes, argTypes.length)
-            (a corresponds p)(_ <:< _)
+            (a corresponds p)((a, f) => a <:< f || weaklyConforms(a, f))
           }
         }
       }
diff --git a/test/files/run/reflect-resolveoverload-invalid.scala b/test/files/run/reflect-resolveoverload-invalid.scala
index def28ccbb4..8c5dc9f94b 100644
--- a/test/files/run/reflect-resolveoverload-invalid.scala
+++ b/test/files/run/reflect-resolveoverload-invalid.scala
@@ -27,7 +27,7 @@ object Test extends App {
   val d = t member u.newTermName("d") asTermSymbol
   val e = t member u.newTermName("e") asTermSymbol
 
-  val n1 = a.resolveOverloaded(posVargs = List(u.typeOf[Char]))
+  val n1 = a.resolveOverloaded(posVargs = List(u.typeOf[Long]))
   val n2 = b.resolveOverloaded(posVargs = List(u.typeOf[A]))
   val n3 = c.resolveOverloaded(posVargs = List(u.typeOf[B], u.typeOf[B]))
   val n4 = d.resolveOverloaded(targs = List(u.typeOf[Int]))
diff --git a/test/files/run/reflect-resolveoverload2.scala b/test/files/run/reflect-resolveoverload2.scala
index b5f719814b..a800a3e92c 100644
--- a/test/files/run/reflect-resolveoverload2.scala
+++ b/test/files/run/reflect-resolveoverload2.scala
@@ -2,16 +2,20 @@ class A
 class B extends A
 
 class C {
-   def a(x: Int) = 1
-   def a(x: String) = 2
-   //def b(x: => Int)(s: String) = 1
-   //def b(x: => String)(a: Array[_]) = 2
-   def c(x: A) = 1
-   def c(x: B) = 2
-   //def d(x: => A)(s: String) = 1
-   //def d(x: => B)(a: Array[_]) = 2
-   def e(x: A) = 1
-   def e(x: B = new B) = 2
+  def a(x: Int) = 1
+  def a(x: String) = 2
+  //def b(x: => Int)(s: String) = 1
+  //def b(x: => String)(a: Array[_]) = 2
+  def c(x: A) = 1
+  def c(x: B) = 2
+  //def d(x: => A)(s: String) = 1
+  //def d(x: => B)(a: Array[_]) = 2
+  def e(x: A) = 1
+  def e(x: B = new B) = 2
+  def f(x: Int) = 1
+  def f(x: String) = 2
+  def f(x: Long) = 3
+  def f(x: Double) = 4
 }
 
 object Test extends App {
@@ -29,6 +33,8 @@ object Test extends App {
   }
   assert(c.a(1) == invoke("a", 1, u.typeOf[Int]))
   assert(c.a("a") == invoke("a", "a", u.typeOf[String]))
+  assert(c.a('a') == invoke("a", 'a', u.typeOf[Char]))
+  assert(c.a(3: Byte) == invoke("a", 3: Byte, u.typeOf[Byte]))
   //assert(c.b(1)(null) == invoke("b", 1, u.typeOf[Int]))
   //assert(c.b("a")(null) == invoke("b", "a", u.typeOf[String]))
   assert(c.c(new A) == invoke("c", new A, u.typeOf[A]))
@@ -37,4 +43,9 @@ object Test extends App {
   //assert(c.d(new B)(null) == invoke("d", new B, u.typeOf[B]))
   assert(c.e(new A) == invoke("e", new A, u.typeOf[A]))
   assert(c.e(new B) == invoke("e", new B, u.typeOf[B]))
+  assert(c.f(1: Short) == invoke("f", 1: Short, u.typeOf[Short]))
+  assert(c.f(2) == invoke("f", 2, u.typeOf[Int]))
+  assert(c.f(3L) == invoke("f", 3L, u.typeOf[Long]))
+  assert(c.f(4f) == invoke("f", 4f, u.typeOf[Float]))
+  assert(c.f(5d) == invoke("f", 5d, u.typeOf[Double]))
 }