Ticket #77: passthrough-no-warn.patch

Source/BinaryOpExpr.cobra

@@ -882 +882 @@
                     else if leftType inherits NilableType and not rightType inherits NilableType and rightType.isStrictDescendantOf(leftType.nonNil)
                         # ex: someNilableShape inherits Circle
                         pass
+                    else if leftType inherits PassThroughType # rightType passThrough shd be an error
+                        pass
                     else if leftType inherits NilableType and not rightType inherits NilableType and leftType.nonNil.isDescendantOf(rightType)
                         # ex: someNilableCircle inherits Shape
                         .compiler.warning(this, 'The expression will always be of type "[.right.toCobraSource]" when not nil. You can just check for not nil by removing "inherits [.right.toCobraSource]".')

Tests/800-warnings/510-passthrough-no-warning.cobra

@@ +1 @@
+class A
+
+    def main is shared
+        #x as int = 1 to passthrough
+        x as passthrough = A() 
+        s = 'notA'
+        if x inherits A
+            #print 'A'
+            s = 'A'
+        assert s == 'A'