implement PEP 479

Author: msimacek

graalpython/com.oracle.graal.python.test/src/tests/test_generators.py

@@ -207,18 +207,19 @@ def gen():
         next(g)
         next(g)
         self.assertEqual(next(g), "done")
-        
 
-    def test_stopiteration_warning(self):
+    @unittest.skipIf(sys.version_info.minor < 7, "Requires Python 3.7+")
+    def test_stopiteration_error(self):
         # See also PEP 479.
 
         def gen():
             raise StopIteration
             yield
 
-        with self.assertRaises(StopIteration):
+        with self.assertRaisesRegex(RuntimeError, 'raised StopIteration'):
             next(gen())
 
+    @unittest.skipIf(sys.version_info.minor < 7, "Requires Python 3.7+")
     def test_tutorial_stopiteration(self):
         # Raise StopIteration" stops the generator too:
 
@@ -230,13 +231,9 @@ def f():
         g = f()
         self.assertEqual(next(g), 1)
 
-        with self.assertRaises(StopIteration):
+        with self.assertRaisesRegex(RuntimeError, 'raised StopIteration'):
             next(g)
 
-        with self.assertRaises(StopIteration):
-            # This time StopIteration isn't raised from the generator's body,
-            # hence no warning.
-            next(g)
 
     # def test_return_tuple(self):
     #     def g():

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/generator/GeneratorReturnTargetNode.java

@@ -25,16 +25,20 @@
  */
 package com.oracle.graal.python.nodes.generator;
 
+import static com.oracle.graal.python.runtime.exception.PythonErrorType.RuntimeError;
 import static com.oracle.graal.python.runtime.exception.PythonErrorType.StopIteration;
 
 import com.oracle.graal.python.builtins.objects.PNone;
 import com.oracle.graal.python.nodes.PRaiseNode;
 import com.oracle.graal.python.nodes.expression.ExpressionNode;
+import com.oracle.graal.python.nodes.object.IsBuiltinClassProfile;
 import com.oracle.graal.python.nodes.statement.StatementNode;
+import com.oracle.graal.python.runtime.exception.PException;
 import com.oracle.graal.python.runtime.exception.ReturnException;
 import com.oracle.graal.python.runtime.exception.YieldException;
 import com.oracle.graal.python.runtime.object.PythonObjectFactory;
 import com.oracle.truffle.api.CompilerDirectives;
+import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.frame.VirtualFrame;
 import com.oracle.truffle.api.profiles.BranchProfile;
 
@@ -50,6 +54,7 @@ public final class GeneratorReturnTargetNode extends ExpressionNode implements G
     private final BranchProfile returnProfile = BranchProfile.create();
     private final BranchProfile fallthroughProfile = BranchProfile.create();
     private final BranchProfile yieldProfile = BranchProfile.create();
+    @CompilationFinal private IsBuiltinClassProfile errorProfile;
 
     private final int flagSlot;
 
@@ -68,6 +73,14 @@ public int getFlagSlot() {
         return flagSlot;
     }
 
+    private IsBuiltinClassProfile getErrorProfile() {
+        if (errorProfile == null) {
+            CompilerDirectives.transferToInterpreterAndInvalidate();
+            errorProfile = IsBuiltinClassProfile.create();
+        }
+        return errorProfile;
+    }
+
     @Override
     public Object execute(VirtualFrame frame) {
         if (!gen.isActive(frame, flagSlot)) {
@@ -76,7 +89,14 @@ public Object execute(VirtualFrame frame) {
         }
 
         try {
-            body.executeVoid(frame);
+            try {
+                body.executeVoid(frame);
+            } catch (PException pe) {
+                // PEP 479 - StopIteration raised from generator body needs to be wrapped in
+                // RuntimeError
+                pe.expectStopIteration(getErrorProfile());
+                throw raise.raise(RuntimeError, pe.getExceptionObject(), "generator raised StopIteration");
+            }
             fallthroughProfile.enter();
             throw raise.raise(StopIteration);
         } catch (YieldException eye) {