diff --git a/_pytest/assertion/rewrite.py b/_pytest/assertion/rewrite.py index fd4f66cd0..921d17a10 100644 --- a/_pytest/assertion/rewrite.py +++ b/_pytest/assertion/rewrite.py @@ -125,7 +125,7 @@ class AssertionRewritingHook(object): co = _read_pyc(fn_pypath, pyc, state.trace) if co is None: state.trace("rewriting %r" % (fn,)) - source_stat, co = _rewrite_test(state, fn_pypath) + source_stat, co = _rewrite_test(self.config, fn_pypath) if co is None: # Probably a SyntaxError in the test. return None @@ -252,8 +252,9 @@ N = "\n".encode("utf-8") cookie_re = re.compile(r"^[ \t\f]*#.*coding[:=][ \t]*[-\w.]+") BOM_UTF8 = '\xef\xbb\xbf' -def _rewrite_test(state, fn): +def _rewrite_test(config, fn): """Try to read and rewrite *fn* and return the code object.""" + state = config._assertstate try: stat = fn.stat() source = fn.read("rb") @@ -298,7 +299,7 @@ def _rewrite_test(state, fn): # Let this pop up again in the real import. state.trace("failed to parse: %r" % (fn,)) return None, None - rewrite_asserts(tree) + rewrite_asserts(tree, fn, config) try: co = compile(tree, fn.strpath, "exec") except SyntaxError: @@ -354,9 +355,9 @@ def _read_pyc(source, pyc, trace=lambda x: None): return co -def rewrite_asserts(mod): +def rewrite_asserts(mod, module_path=None, config=None): """Rewrite the assert statements in mod.""" - AssertionRewriter().run(mod) + AssertionRewriter(module_path, config).run(mod) def _saferepr(obj): @@ -543,6 +544,11 @@ class AssertionRewriter(ast.NodeVisitor): """ + def __init__(self, module_path, config): + super(AssertionRewriter, self).__init__() + self.module_path = module_path + self.config = config + def run(self, mod): """Find all assert statements in *mod* and rewrite them.""" if not mod.body: @@ -683,6 +689,10 @@ class AssertionRewriter(ast.NodeVisitor): the expression is false. """ + if isinstance(assert_.test, ast.Tuple) and self.config is not None: + fslocation = (self.module_path, assert_.lineno) + self.config.warn('R1', 'assertion is always true, perhaps ' + 'remove parentheses?', fslocation=fslocation) self.statements = [] self.variables = [] self.variable_counter = itertools.count() diff --git a/testing/test_assertion.py b/testing/test_assertion.py index dfa1b9420..4694bb261 100644 --- a/testing/test_assertion.py +++ b/testing/test_assertion.py @@ -640,3 +640,11 @@ def test_diff_newline_at_end(monkeypatch, testdir): * + asdf * ? + """) + +def test_assert_tuple_warning(testdir): + testdir.makepyfile(""" + def test_tuple(): + assert(False, 'you shall not pass') + """) + result = testdir.runpytest('-rw') + result.stdout.fnmatch_lines('WR1*:2 assertion is always true*')