Python3.5: Detect yield in coroutines as an error.

nuitka/tree/ReformulationYieldExpressions.py

@@ -22,6 +22,8 @@
 
 """
 
+import ast
+
 from nuitka.nodes.BuiltinIteratorNodes import ExpressionBuiltinIter1
 from nuitka.nodes.ConstantRefNodes import ExpressionConstantRef
 from nuitka.nodes.YieldNodes import ExpressionYield, ExpressionYieldFrom
@@ -39,6 +41,15 @@ def _markAsGenerator(provider, node, source_ref):
             None if Utils.python_version < 300 else node.col_offset
         )
 
+    if provider.isExpressionCoroutineBody():
+        SyntaxErrors.raiseSyntaxError(
+            "'%s' inside async function" % (
+                "yield" if node.__class__ is ast.Yield else "yield from",
+            ),
+            source_ref,
+            node.col_offset+3
+        )
+
     assert provider.isExpressionGeneratorObjectBody(), provider
 
 

tests/syntax/YieldFromInModule.py

@@ -0,0 +1,20 @@
+#     Copyright 2015, Kay Hayen, mailto:[email protected]
+#
+#     Python tests originally created or extracted from other peoples work. The
+#     parts were too small to be protected.
+#
+#     Licensed under the Apache License, Version 2.0 (the "License");
+#     you may not use this file except in compliance with the License.
+#     You may obtain a copy of the License at
+#
+#        http://www.apache.org/licenses/LICENSE-2.0
+#
+#     Unless required by applicable law or agreed to in writing, software
+#     distributed under the License is distributed on an "AS IS" BASIS,
+#     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#     See the License for the specific language governing permissions and
+#     limitations under the License.
+#
+
+x = (i for i in
+(yield from range(7)) if (yield from range(2)))

tests/syntax/YieldInAsync35.py

@@ -0,0 +1,20 @@
+#     Copyright 2015, Kay Hayen, mailto:[email protected]
+#
+#     Python tests originally created or extracted from other peoples work. The
+#     parts were too small to be protected.
+#
+#     Licensed under the Apache License, Version 2.0 (the "License");
+#     you may not use this file except in compliance with the License.
+#     You may obtain a copy of the License at
+#
+#        http://www.apache.org/licenses/LICENSE-2.0
+#
+#     Unless required by applicable law or agreed to in writing, software
+#     distributed under the License is distributed on an "AS IS" BASIS,
+#     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#     See the License for the specific language governing permissions and
+#     limitations under the License.
+#
+async def g():
+   yield from None
+