Merge pull request #5376 from asottile/backport_5373

[4.6] Merge pull request #5373 from asottile/revert_all_handling

Author: asottile

changelog/5370.bugfix.rst

@@ -0,0 +1 @@
+Revert unrolling of ``all()`` to fix ``NameError`` on nested comprehensions.

changelog/5371.bugfix.rst

@@ -0,0 +1 @@
+Revert unrolling of ``all()`` to fix incorrect handling of generators with ``if``.

changelog/5372.bugfix.rst

@@ -0,0 +1 @@
+Revert unrolling of ``all()`` to fix incorrect assertion when using ``all()`` in an expression.

src/_pytest/assertion/rewrite.py

@@ -949,22 +949,10 @@ def visit_BinOp(self, binop):
         res = self.assign(ast.BinOp(left_expr, binop.op, right_expr))
         return res, explanation
 
-    @staticmethod
-    def _is_any_call_with_generator_or_list_comprehension(call):
-        """Return True if the Call node is an 'any' call with a generator or list comprehension"""
-        return (
-            isinstance(call.func, ast.Name)
-            and call.func.id == "all"
-            and len(call.args) == 1
-            and isinstance(call.args[0], (ast.GeneratorExp, ast.ListComp))
-        )
-
     def visit_Call_35(self, call):
         """
         visit `ast.Call` nodes on Python3.5 and after
         """
-        if self._is_any_call_with_generator_or_list_comprehension(call):
-            return self._visit_all(call)
         new_func, func_expl = self.visit(call.func)
         arg_expls = []
         new_args = []
@@ -988,25 +976,6 @@ def visit_Call_35(self, call):
         outer_expl = "%s\n{%s = %s\n}" % (res_expl, res_expl, expl)
         return res, outer_expl
 
-    def _visit_all(self, call):
-        """Special rewrite for the builtin all function, see #5062"""
-        gen_exp = call.args[0]
-        assertion_module = ast.Module(
-            body=[ast.Assert(test=gen_exp.elt, lineno=1, msg="", col_offset=1)]
-        )
-        AssertionRewriter(module_path=None, config=None).run(assertion_module)
-        for_loop = ast.For(
-            iter=gen_exp.generators[0].iter,
-            target=gen_exp.generators[0].target,
-            body=assertion_module.body,
-            orelse=[],
-        )
-        self.statements.append(for_loop)
-        return (
-            ast.Num(n=1),
-            "",
-        )  # Return an empty expression, all the asserts are in the for_loop
-
     def visit_Starred(self, starred):
         # From Python 3.5, a Starred node can appear in a function call
         res, expl = self.visit(starred.value)
@@ -1017,8 +986,6 @@ def visit_Call_legacy(self, call):
         """
         visit `ast.Call nodes on 3.4 and below`
         """
-        if self._is_any_call_with_generator_or_list_comprehension(call):
-            return self._visit_all(call)
         new_func, func_expl = self.visit(call.func)
         arg_expls = []
         new_args = []

testing/test_assertrewrite.py

@@ -656,12 +656,6 @@ def __repr__(self):
         else:
             assert lines == ["assert 0 == 1\n +  where 1 = \\n{ \\n~ \\n}.a"]
 
-    def test_unroll_expression(self):
-        def f():
-            assert all(x == 1 for x in range(10))
-
-        assert "0 == 1" in getmsg(f)
-
     def test_custom_repr_non_ascii(self):
         def f():
             class A(object):
@@ -677,78 +671,6 @@ def __repr__(self):
         assert "UnicodeDecodeError" not in msg
         assert "UnicodeEncodeError" not in msg
 
-    def test_unroll_all_generator(self, testdir):
-        testdir.makepyfile(
-            """
-            def check_even(num):
-                if num % 2 == 0:
-                    return True
-                return False
-
-            def test_generator():
-                odd_list = list(range(1,9,2))
-                assert all(check_even(num) for num in odd_list)"""
-        )
-        result = testdir.runpytest()
-        result.stdout.fnmatch_lines(["*assert False*", "*where False = check_even(1)*"])
-
-    def test_unroll_all_list_comprehension(self, testdir):
-        testdir.makepyfile(
-            """
-            def check_even(num):
-                if num % 2 == 0:
-                    return True
-                return False
-
-            def test_list_comprehension():
-                odd_list = list(range(1,9,2))
-                assert all([check_even(num) for num in odd_list])"""
-        )
-        result = testdir.runpytest()
-        result.stdout.fnmatch_lines(["*assert False*", "*where False = check_even(1)*"])
-
-    def test_unroll_all_object(self, testdir):
-        """all() for non generators/non list-comprehensions (#5358)"""
-        testdir.makepyfile(
-            """
-            def test():
-                assert all((1, 0))
-            """
-        )
-        result = testdir.runpytest()
-        result.stdout.fnmatch_lines(["*assert False*", "*where False = all((1, 0))*"])
-
-    def test_unroll_all_starred(self, testdir):
-        """all() for non generators/non list-comprehensions (#5358)"""
-        testdir.makepyfile(
-            """
-            def test():
-                x = ((1, 0),)
-                assert all(*x)
-            """
-        )
-        result = testdir.runpytest()
-        result.stdout.fnmatch_lines(
-            ["*assert False*", "*where False = all(*((1, 0),))*"]
-        )
-
-    def test_for_loop(self, testdir):
-        testdir.makepyfile(
-            """
-            def check_even(num):
-                if num % 2 == 0:
-                    return True
-                return False
-
-            def test_for_loop():
-                odd_list = list(range(1,9,2))
-                for num in odd_list:
-                    assert check_even(num)
-        """
-        )
-        result = testdir.runpytest()
-        result.stdout.fnmatch_lines(["*assert False*", "*where False = check_even(1)*"])
-
 
 class TestRewriteOnImport(object):
     def test_pycache_is_a_file(self, testdir):