teach 2to3 about 'yield from'
diff --git a/Lib/lib2to3/Grammar.txt b/Lib/lib2to3/Grammar.txt
index bc084e9..e667bcd 100644
--- a/Lib/lib2to3/Grammar.txt
+++ b/Lib/lib2to3/Grammar.txt
@@ -155,4 +155,5 @@
# not used in grammar, but may appear in "node" passed from Parser to Compiler
encoding_decl: NAME
-yield_expr: 'yield' [testlist]
+yield_expr: 'yield' [yield_arg]
+yield_arg: 'from' test | testlist
diff --git a/Lib/lib2to3/tests/test_parser.py b/Lib/lib2to3/tests/test_parser.py
index 2e5af45..9c5463a 100644
--- a/Lib/lib2to3/tests/test_parser.py
+++ b/Lib/lib2to3/tests/test_parser.py
@@ -50,6 +50,13 @@
self.validate("a @= b")
+class TestYieldFrom(GrammarTest):
+ def test_matrix_multiplication_operator(self):
+ self.validate("yield from x")
+ self.validate("(yield from x) + y")
+ self.invalid_syntax("yield from")
+
+
class TestRaiseChanges(GrammarTest):
def test_2x_style_1(self):
self.validate("raise")
diff --git a/Misc/NEWS b/Misc/NEWS
index fb06c01..7756e89 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -266,6 +266,8 @@
Tools/Demos
-----------
+- Add support for ``yield from`` to 2to3.
+
- Add support for the PEP 465 matrix multiplication operator to 2to3.
- Issue #19936: Added executable bits or shebang lines to Python scripts which