diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/test/test_named_expressions.py | 80 |
1 files changed, 78 insertions, 2 deletions
diff --git a/Lib/test/test_named_expressions.py b/Lib/test/test_named_expressions.py index 20ac2e6..7b2fa84 100644 --- a/Lib/test/test_named_expressions.py +++ b/Lib/test/test_named_expressions.py @@ -114,6 +114,69 @@ class NamedExpressionInvalidTest(unittest.TestCase): "assignment expression within a comprehension cannot be used in a class body"): exec(code, {}, {}) + def test_named_expression_valid_rebinding_iteration_variable(self): + # This test covers that we can reassign variables + # that are not directly assigned in the + # iterable part of a comprehension. + cases = [ + # Regression tests from https://github.com/python/cpython/issues/87447 + ("Complex expression: c", + "{0}(c := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: d", + "{0}(d := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: e", + "{0}(e := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: f", + "{0}(f := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: g", + "{0}(g := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: h", + "{0}(h := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: i", + "{0}(i := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: j", + "{0}(j := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ] + for test_case, code in cases: + for lpar, rpar in [('(', ')'), ('[', ']'), ('{', '}')]: + code = code.format(lpar, rpar) + with self.subTest(case=test_case, lpar=lpar, rpar=rpar): + # Names used in snippets are not defined, + # but we are fine with it: just must not be a SyntaxError. + # Names used in snippets are not defined, + # but we are fine with it: just must not be a SyntaxError. + with self.assertRaises(NameError): + exec(code, {}) # Module scope + with self.assertRaises(NameError): + exec(code, {}, {}) # Class scope + exec(f"lambda: {code}", {}) # Function scope + + def test_named_expression_invalid_rebinding_iteration_variable(self): + # This test covers that we cannot reassign variables + # that are directly assigned in the iterable part of a comprehension. + cases = [ + # Regression tests from https://github.com/python/cpython/issues/87447 + ("Complex expression: a", "a", + "{0}(a := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ("Complex expression: b", "b", + "{0}(b := 1) for a, (*b, c[d+e::f(g)], h.i) in j{1}"), + ] + for test_case, target, code in cases: + msg = f"assignment expression cannot rebind comprehension iteration variable '{target}'" + for lpar, rpar in [('(', ')'), ('[', ']'), ('{', '}')]: + code = code.format(lpar, rpar) + with self.subTest(case=test_case, lpar=lpar, rpar=rpar): + # Names used in snippets are not defined, + # but we are fine with it: just must not be a SyntaxError. + # Names used in snippets are not defined, + # but we are fine with it: just must not be a SyntaxError. + with self.assertRaisesRegex(SyntaxError, msg): + exec(code, {}) # Module scope + with self.assertRaisesRegex(SyntaxError, msg): + exec(code, {}, {}) # Class scope + with self.assertRaisesRegex(SyntaxError, msg): + exec(f"lambda: {code}", {}) # Function scope + def test_named_expression_invalid_rebinding_list_comprehension_iteration_variable(self): cases = [ ("Local reuse", 'i', "[i := 0 for i in range(5)]"), @@ -129,7 +192,11 @@ class NamedExpressionInvalidTest(unittest.TestCase): msg = f"assignment expression cannot rebind comprehension iteration variable '{target}'" with self.subTest(case=case): with self.assertRaisesRegex(SyntaxError, msg): - exec(code, {}, {}) + exec(code, {}) # Module scope + with self.assertRaisesRegex(SyntaxError, msg): + exec(code, {}, {}) # Class scope + with self.assertRaisesRegex(SyntaxError, msg): + exec(f"lambda: {code}", {}) # Function scope def test_named_expression_invalid_rebinding_list_comprehension_inner_loop(self): cases = [ @@ -178,12 +245,21 @@ class NamedExpressionInvalidTest(unittest.TestCase): ("Unreachable reuse", 'i', "{False or (i:=0) for i in range(5)}"), ("Unreachable nested reuse", 'i', "{(i, j) for i in range(5) for j in range(5) if True or (i:=10)}"), + # Regression tests from https://github.com/python/cpython/issues/87447 + ("Complex expression: a", "a", + "{(a := 1) for a, (*b, c[d+e::f(g)], h.i) in j}"), + ("Complex expression: b", "b", + "{(b := 1) for a, (*b, c[d+e::f(g)], h.i) in j}"), ] for case, target, code in cases: msg = f"assignment expression cannot rebind comprehension iteration variable '{target}'" with self.subTest(case=case): with self.assertRaisesRegex(SyntaxError, msg): - exec(code, {}, {}) + exec(code, {}) # Module scope + with self.assertRaisesRegex(SyntaxError, msg): + exec(code, {}, {}) # Class scope + with self.assertRaisesRegex(SyntaxError, msg): + exec(f"lambda: {code}", {}) # Function scope def test_named_expression_invalid_rebinding_set_comprehension_inner_loop(self): cases = [ |