1 files changed, 14 insertions, 0 deletions
diff --git a/Lib/test/test_peepholer.py b/Lib/test/test_peepholer.py
index 567e6a1..7913e91 100644
--- a/Lib/test/test_peepholer.py
+++ b/Lib/test/test_peepholer.py
@@ -495,6 +495,20 @@ class TestTranforms(BytecodeTestCase):
             return 6
         self.check_lnotab(f)
 
+    def test_assignment_idiom_in_comprehensions(self):
+        def listcomp():
+            return [y for x in a for y in [f(x)]]
+        self.assertEqual(count_instr_recursively(listcomp, 'FOR_ITER'), 1)
+        def setcomp():
+            return {y for x in a for y in [f(x)]}
+        self.assertEqual(count_instr_recursively(setcomp, 'FOR_ITER'), 1)
+        def dictcomp():
+            return {y: y for x in a for y in [f(x)]}
+        self.assertEqual(count_instr_recursively(dictcomp, 'FOR_ITER'), 1)
+        def genexpr():
+            return (y for x in a for y in [f(x)])
+        self.assertEqual(count_instr_recursively(genexpr, 'FOR_ITER'), 1)
+
 
 class TestBuglets(unittest.TestCase):