test_ok2/testing/test_assertrewrite.py

251 lines
7.2 KiB
Python

import sys
import py
import pytest
ast = pytest.importorskip("ast")
from _pytest.assertion import util
from _pytest.assertion.rewrite import rewrite_asserts
def setup_module(mod):
mod._old_reprcompare = util._reprcompare
py.code._reprcompare = None
def teardown_module(mod):
util._reprcompare = mod._old_reprcompare
del mod._old_reprcompare
def rewrite(src):
tree = ast.parse(src)
rewrite_asserts(tree)
return tree
def getmsg(f, extra_ns=None, must_pass=False):
"""Rewrite the assertions in f, run it, and get the failure message."""
src = '\n'.join(py.code.Code(f).source().lines)
mod = rewrite(src)
code = compile(mod, "<test>", "exec")
ns = {}
if extra_ns is not None:
ns.update(extra_ns)
py.builtin.exec_(code, ns)
func = ns[f.__name__]
try:
func()
except AssertionError:
if must_pass:
pytest.fail("shouldn't have raised")
s = str(sys.exc_info()[1])
if not s.startswith("assert"):
return "AssertionError: " + s
return s
else:
if not must_pass:
pytest.fail("function didn't raise at all")
class TestAssertionRewrite:
def test_place_initial_imports(self):
s = """'Doc string'\nother = stuff"""
m = rewrite(s)
assert isinstance(m.body[0], ast.Expr)
assert isinstance(m.body[0].value, ast.Str)
for imp in m.body[1:3]:
assert isinstance(imp, ast.Import)
assert imp.lineno == 2
assert imp.col_offset == 0
assert isinstance(m.body[3], ast.Assign)
s = """from __future__ import with_statement\nother_stuff"""
m = rewrite(s)
assert isinstance(m.body[0], ast.ImportFrom)
for imp in m.body[1:3]:
assert isinstance(imp, ast.Import)
assert imp.lineno == 2
assert imp.col_offset == 0
assert isinstance(m.body[3], ast.Expr)
s = """'doc string'\nfrom __future__ import with_statement\nother"""
m = rewrite(s)
assert isinstance(m.body[0], ast.Expr)
assert isinstance(m.body[0].value, ast.Str)
assert isinstance(m.body[1], ast.ImportFrom)
for imp in m.body[2:4]:
assert isinstance(imp, ast.Import)
assert imp.lineno == 3
assert imp.col_offset == 0
assert isinstance(m.body[4], ast.Expr)
def test_dont_rewrite(self):
s = """'PYTEST_DONT_REWRITE'\nassert 14"""
m = rewrite(s)
assert len(m.body) == 2
assert isinstance(m.body[0].value, ast.Str)
assert isinstance(m.body[1], ast.Assert)
assert m.body[1].msg is None
def test_name(self):
def f():
assert False
assert getmsg(f) == "assert False"
def f():
f = False
assert f
assert getmsg(f) == "assert False"
def f():
assert a_global
assert getmsg(f, {"a_global" : False}) == "assert a_global"
def test_assert_already_has_message(self):
def f():
assert False, "something bad!"
assert getmsg(f) == "AssertionError: something bad!"
def test_boolop(self):
def f():
f = g = False
assert f and g
assert getmsg(f) == "assert (False)"
def f():
f = True
g = False
assert f and g
assert getmsg(f) == "assert (True and False)"
def f():
f = False
g = True
assert f and g
assert getmsg(f) == "assert (False)"
def f():
f = g = False
assert f or g
assert getmsg(f) == "assert (False or False)"
def f():
f = True
g = False
assert f or g
getmsg(f, must_pass=True)
def test_short_circut_evaluation(self):
pytest.xfail("complicated fix; I'm not sure if it's important")
def f():
assert True or explode
getmsg(f, must_pass=True)
def test_unary_op(self):
def f():
x = True
assert not x
assert getmsg(f) == "assert not True"
def f():
x = 0
assert ~x + 1
assert getmsg(f) == "assert (~0 + 1)"
def f():
x = 3
assert -x + x
assert getmsg(f) == "assert (-3 + 3)"
def f():
x = 0
assert +x + x
assert getmsg(f) == "assert (+0 + 0)"
def test_binary_op(self):
def f():
x = 1
y = -1
assert x + y
assert getmsg(f) == "assert (1 + -1)"
def test_call(self):
def g(a=42, *args, **kwargs):
return False
ns = {"g" : g}
def f():
assert g()
assert getmsg(f, ns) == """assert g()"""
def f():
assert g(1)
assert getmsg(f, ns) == """assert g(1)"""
def f():
assert g(1, 2)
assert getmsg(f, ns) == """assert g(1, 2)"""
def f():
assert g(1, g=42)
assert getmsg(f, ns) == """assert g(1, g=42)"""
def f():
assert g(1, 3, g=23)
assert getmsg(f, ns) == """assert g(1, 3, g=23)"""
def test_attribute(self):
class X(object):
g = 3
ns = {"X" : X, "x" : X()}
def f():
assert not x.g
assert getmsg(f, ns) == """assert not 3
+ where 3 = x.g"""
def f():
x.a = False
assert x.a
assert getmsg(f, ns) == """assert x.a"""
def test_comparisons(self):
def f():
a, b = range(2)
assert b < a
assert getmsg(f) == """assert 1 < 0"""
def f():
a, b, c = range(3)
assert a > b > c
assert getmsg(f) == """assert 0 > 1"""
def f():
a, b, c = range(3)
assert a < b > c
assert getmsg(f) == """assert 1 > 2"""
def f():
a, b, c = range(3)
assert a < b <= c
getmsg(f, must_pass=True)
def f():
a, b, c = range(3)
assert a < b
assert b < c
getmsg(f, must_pass=True)
def test_len(self):
def f():
l = list(range(10))
assert len(l) == 11
assert getmsg(f).startswith("""assert 10 == 11
+ where 10 = len([""")
def test_custom_reprcompare(self, monkeypatch):
def my_reprcompare(op, left, right):
return "42"
monkeypatch.setattr(util, "_reprcompare", my_reprcompare)
def f():
assert 42 < 3
assert getmsg(f) == "assert 42"
def my_reprcompare(op, left, right):
return "%s %s %s" % (left, op, right)
monkeypatch.setattr(util, "_reprcompare", my_reprcompare)
def f():
assert 1 < 3 < 5 <= 4 < 7
assert getmsg(f) == "assert 5 <= 4"
def test_assert_raising_nonzero_in_comparison(self):
def f():
class A(object):
def __nonzero__(self):
raise ValueError(42)
def __lt__(self, other):
return A()
def __repr__(self):
return "<MY42 object>"
def myany(x):
return False
assert myany(A() < 0)
assert "<MY42 object> < 0" in getmsg(f)