Added tests for the new yield support in the parser module.

(Should be merged with descr branch.)

Lib/test/test_parser.py

@@ -26,6 +26,18 @@ class RoundtripLegalSyntaxTestCase(unittest.TestCase):
     def check_suite(self, s):
         self.roundtrip(parser.suite, s)
 
+    def test_yield_statement(self):
+        self.check_suite("from __future__ import generators\n"
+                         "def f(): yield 1")
+        self.check_suite("from __future__ import generators\n"
+                         "def f(): return; yield 1")
+        self.check_suite("from __future__ import generators\n"
+                         "def f(): yield 1; return")
+        self.check_suite("from __future__ import generators\n"
+                         "def f():\n"
+                         "    for x in range(30):\n"
+                         "        yield x\n")
+
     def test_expressions(self):
         self.check_expr("foo(1)")
         self.check_expr("[1, 2, 3]")
@@ -138,8 +150,127 @@ class IllegalSyntaxTestCase(unittest.TestCase):
         # not even remotely valid:
         self.check_bad_tree((1, 2, 3), "<junk>")
 
+    def test_illegal_yield_1(self):
+        """Illegal yield statement: def f(): return 1; yield 1"""
+        tree = \
+        (257,
+         (264,
+          (285,
+           (259,
+            (1, 'def'),
+            (1, 'f'),
+            (260, (7, '('), (8, ')')),
+            (11, ':'),
+            (291,
+             (4, ''),
+             (5, ''),
+             (264,
+              (265,
+               (266,
+                (272,
+                 (275,
+                  (1, 'return'),
+                  (313,
+                   (292,
+                    (293,
+                     (294,
+                      (295,
+                       (297,
+                        (298,
+                         (299,
+                          (300,
+                           (301,
+                            (302, (303, (304, (305, (2, '1')))))))))))))))))),
+               (264,
+                (265,
+                 (266,
+                  (272,
+                   (276,
+                    (1, 'yield'),
+                    (313,
+                     (292,
+                      (293,
+                       (294,
+                        (295,
+                         (297,
+                          (298,
+                           (299,
+                            (300,
+                             (301,
+                              (302,
+                               (303, (304, (305, (2, '1')))))))))))))))))),
+                 (4, ''))),
+               (6, ''))))),
+           (4, ''),
+           (0, ''))))
+        self.check_bad_tree(tree, "def f():\n  return 1\n  yield 1")
+
+    def test_illegal_yield_2(self):
+        """Illegal return in generator: def f(): return 1; yield 1"""
+        tree = \
+        (257,
+         (264,
+          (265,
+           (266,
+            (278,
+             (1, 'from'),
+             (281, (1, '__future__')),
+             (1, 'import'),
+             (279, (1, 'generators')))),
+           (4, ''))),
+         (264,
+          (285,
+           (259,
+            (1, 'def'),
+            (1, 'f'),
+            (260, (7, '('), (8, ')')),
+            (11, ':'),
+            (291,
+             (4, ''),
+             (5, ''),
+             (264,
+              (265,
+               (266,
+                (272,
+                 (275,
+                  (1, 'return'),
+                  (313,
+                   (292,
+                    (293,
+                     (294,
+                      (295,
+                       (297,
+                        (298,
+                         (299,
+                          (300,
+                           (301,
+                            (302, (303, (304, (305, (2, '1')))))))))))))))))),
+               (264,
+                (265,
+                 (266,
+                  (272,
+                   (276,
+                    (1, 'yield'),
+                    (313,
+                     (292,
+                      (293,
+                       (294,
+                        (295,
+                         (297,
+                          (298,
+                           (299,
+                            (300,
+                             (301,
+                              (302,
+                               (303, (304, (305, (2, '1')))))))))))))))))),
+                 (4, ''))),
+               (6, ''))))),
+           (4, ''),
+           (0, ''))))
+        self.check_bad_tree(tree, "def f():\n  return 1\n  yield 1")
+
     def test_print_chevron_comma(self):
-        "Illegal input: print >>fp,"""
+        """Illegal input: print >>fp,"""
         tree = \
         (257,
          (264,