pytest_percent_logic.py

from __future__ import unicode_literals


class Explode():
    def __repr__(self):
        return '(1/0)'
explode = Explode()

class Expr(object):
    def __init__(self, percent_expr, logic_op, bool_expr, percent_first, percent_char):
        percent_expr = percent_expr.replace('%', percent_char)

        self.percent_expr = '({} {} {})'.format(*percent_expr)
        self.logic_op = logic_op
        self.bool_expr = bool_expr
        self.percent_first = percent_first
        self.percent_char = percent_char

    def expr(self, explode_per=False):
        percent_expr = self.percent_expr
        if explode_per:
            percent_expr = explode
        if not self.percent_first:
            return '{} {} {}'.format(percent_expr, self.logic_op, self.bool_expr)
        return '{} {} {}'.format(self.bool_expr, self.logic_op, percent_expr)

    def asserts_true(self):
        return bool(eval(self.expr()))

    def percent_is_evaled(self):
        try:
            eval(self.expr(explode_per=True))
        except ZeroDivisionError:
            return True
        else:
            return False

    def function_name(self):
        return (self.expr().replace('-', 'sub')
            .replace(' ', '_') .replace('(', '')
            .replace(')', '') .replace('%', 'mod'))

    def function_docstring(self):
        return 'Asserts: {}. Percent {} evaled'.format(self.asserts_true(),
            '*is*' if self.percent_is_evaled() else 'is *not*')

    def short_cirtuit_expr(self):
        "Trim off unevaled sub-expression"
        if self.percent_is_evaled():
            return self.expr()
        return '({})'.format(self.bool_expr)

    def getmsg(self):
        if self.asserts_true():
            return 'getmsg(f, must_pass=True)'
        if not self.percent_is_evaled():
            return 'assert getmsg(f) == "assert {}"'.format(self.short_cirtuit_expr())
        return """
        try:
            getmsg(f) == "assert {}"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {{!r}}".format(e))
        """.strip().format(self.short_cirtuit_expr())

    def __unicode__(self):
        return """
    def test_{}(self):
        "{}"
        def f():
            assert {}
        {}
        """.strip('\n').format(self.function_name(), self.function_docstring(), self.expr(), self.getmsg())

    def __repr__(self):
        return self.expr()

    @property
    def ordering(self):
        return self.percent_char, self.asserts_true(), self.percent_is_evaled()

    def __cmp__(self, other):
        return cmp(self.ordering, other.ordering)

    def __hash__(self):
        return hash(self.expr())


def generate_all_cases():
    for logic_op in ('and', 'or'):
        for percent_first in (True, False):
            for bool_expr in ('True', 'False'):
                # eval as 1 and 0
                for percent_expr in ('3%2', '1%1'):
                    # repeat all with '-' to check that expressions are correct,
                    # once the ValueError is fixed.
                    for percent_char in ('%', '-'):
                        yield Expr(percent_expr, logic_op, bool_expr, percent_first, percent_char)

def main():
    new_tests = '\n'.join(map(unicode,
        sorted(generate_all_cases())
    ))
    print new_tests

    test_source_in_fn = "pytest-git-remote-2/testing/test_assertrewrite_input.py"
    test_source_out_fn = "pytest-git-remote-2/testing/test_assertrewrite_output.py"

    test_source = open(test_source_in_fn).read()
    test_source = test_source.replace('# percent test here', new_tests)
    open(test_source_out_fn, 'w').write(test_source)


def test_unique_cases():
    cases = list(generate_all_cases())
    assert len(cases) == len(set(cases))

if __name__ == '__main__':
    import pytest
    fails = pytest.main(__file__)
    assert not fails
    main()

rewritten_test.py

"""
# generate rewritten code using `meta`, the ast reverse parsing tool:
# https://srossross.github.io/Meta/html/api/asttools.html#meta.asttools.python_source

# edit rewrite in testing/test_assertrewrite.py
def rewrite(src):
    tree = ast.parse(src)
    rewrite_asserts(tree)

    # insert these 2 lines:
    import meta
    meta.asttools.python_source(tree) # remove '@'s to enable running

    return tree

# The test being rewritten here:

class TestAssertionRewriteCompoundAssertWithPercent:
    def test_and_or_percent(self):
        # issue 615 - ValueError on compound assert with percent
        def f():
            assert 3 % 2 and False
        assert getmsg(f) == "assert ((3 % 2) and False)"

See inline comments below showing how ValueError arises:
"""

import __builtin__ as py_builtins
import _pytest.assertion.rewrite as pytest_ar
def f():
    py_assert1 = []
    py_assert2 = 3
    py_assert4 = 2
    py_assert6 = (py_assert2 % py_assert4)
    py_assert0 = py_assert6
    if py_assert6:
        py_assert0 = False

    if (not py_assert0):
        # as expected py_format7 recieves a `%` here (the `%%` becomes a single `%` after formatting)
        py_format7 = ('(%(py3)s %% %(py5)s)' % {'py3':pytest_ar._saferepr(py_assert2), 'py5':pytest_ar._saferepr(py_assert4)})
        # py_assert1 here gains the item with the `%`:
        py_assert1.append(py_format7)
        if py_assert6:
            py_format9 = ('%(py8)s' % {'py8':pytest_ar._saferepr(False) if (('False' in py_builtins.locals()) or pytest_ar._should_repr_global_name(False)) else 'False'})
            py_assert1.append(py_format9)
        # Here pytest_ar._format_boolop(py_assert1, 0) allows the `%` to pass through unescaped
        # then ValueErrors when used as a percent format string, which in this case
        # should contain no unescaped percents, as an empty formatting dict is supplied.
        py_format10 = (pytest_ar._format_boolop(py_assert1, 0) % {})
        py_format12 = ('assert %(py11)s' % {'py11':py_format10})
        raise AssertionError(pytest_ar._format_explanation(py_format12))
    py_assert0 = py_assert1 = py_assert2 = py_assert4 = py_assert6 = None

test_assertrewrite_input.py

import pytest

from test_assertrewrite import getmsg


class TestAssertionRewriteCompoundAssertWithPercent:

# start inserted code
# percent test here
# end inserted code

test_assertrewrite_output.py

import pytest

from test_assertrewrite import getmsg


class TestAssertionRewriteCompoundAssertWithPercent:

# start inserted code
    def test_False_and_3_mod_2(self):
        "Asserts: False. Percent is *not* evaled"
        def f():
            assert False and (3 % 2)
        assert getmsg(f) == "assert (False)"
        
    def test_False_and_1_mod_1(self):
        "Asserts: False. Percent is *not* evaled"
        def f():
            assert False and (1 % 1)
        assert getmsg(f) == "assert (False)"
        
    def test_True_and_1_mod_1(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert True and (1 % 1)
        try:
            getmsg(f) == "assert True and (1 % 1)"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_1_mod_1_and_True(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (1 % 1) and True
        try:
            getmsg(f) == "assert (1 % 1) and True"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_3_mod_2_and_False(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (3 % 2) and False
        try:
            getmsg(f) == "assert (3 % 2) and False"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_1_mod_1_and_False(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (1 % 1) and False
        try:
            getmsg(f) == "assert (1 % 1) and False"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_False_or_1_mod_1(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert False or (1 % 1)
        try:
            getmsg(f) == "assert False or (1 % 1)"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_1_mod_1_or_False(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (1 % 1) or False
        try:
            getmsg(f) == "assert (1 % 1) or False"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_True_or_3_mod_2(self):
        "Asserts: True. Percent is *not* evaled"
        def f():
            assert True or (3 % 2)
        getmsg(f, must_pass=True)
        
    def test_True_or_1_mod_1(self):
        "Asserts: True. Percent is *not* evaled"
        def f():
            assert True or (1 % 1)
        getmsg(f, must_pass=True)
        
    def test_True_and_3_mod_2(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert True and (3 % 2)
        getmsg(f, must_pass=True)
        
    def test_3_mod_2_and_True(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (3 % 2) and True
        getmsg(f, must_pass=True)
        
    def test_False_or_3_mod_2(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert False or (3 % 2)
        getmsg(f, must_pass=True)
        
    def test_3_mod_2_or_True(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (3 % 2) or True
        getmsg(f, must_pass=True)
        
    def test_1_mod_1_or_True(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (1 % 1) or True
        getmsg(f, must_pass=True)
        
    def test_3_mod_2_or_False(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (3 % 2) or False
        getmsg(f, must_pass=True)
        
    def test_False_and_3_sub_2(self):
        "Asserts: False. Percent is *not* evaled"
        def f():
            assert False and (3 - 2)
        assert getmsg(f) == "assert (False)"
        
    def test_False_and_1_sub_1(self):
        "Asserts: False. Percent is *not* evaled"
        def f():
            assert False and (1 - 1)
        assert getmsg(f) == "assert (False)"
        
    def test_True_and_1_sub_1(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert True and (1 - 1)
        try:
            getmsg(f) == "assert True and (1 - 1)"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_1_sub_1_and_True(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (1 - 1) and True
        try:
            getmsg(f) == "assert (1 - 1) and True"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_3_sub_2_and_False(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (3 - 2) and False
        try:
            getmsg(f) == "assert (3 - 2) and False"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_1_sub_1_and_False(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (1 - 1) and False
        try:
            getmsg(f) == "assert (1 - 1) and False"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_False_or_1_sub_1(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert False or (1 - 1)
        try:
            getmsg(f) == "assert False or (1 - 1)"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_1_sub_1_or_False(self):
        "Asserts: False. Percent *is* evaled"
        def f():
            assert (1 - 1) or False
        try:
            getmsg(f) == "assert (1 - 1) or False"
        except ValueError as e:
            pytest.xfail("issue 615 - ValueError on compound assert with percent: {!r}".format(e))
        
    def test_True_or_3_sub_2(self):
        "Asserts: True. Percent is *not* evaled"
        def f():
            assert True or (3 - 2)
        getmsg(f, must_pass=True)
        
    def test_True_or_1_sub_1(self):
        "Asserts: True. Percent is *not* evaled"
        def f():
            assert True or (1 - 1)
        getmsg(f, must_pass=True)
        
    def test_True_and_3_sub_2(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert True and (3 - 2)
        getmsg(f, must_pass=True)
        
    def test_3_sub_2_and_True(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (3 - 2) and True
        getmsg(f, must_pass=True)
        
    def test_False_or_3_sub_2(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert False or (3 - 2)
        getmsg(f, must_pass=True)
        
    def test_3_sub_2_or_True(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (3 - 2) or True
        getmsg(f, must_pass=True)
        
    def test_1_sub_1_or_True(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (1 - 1) or True
        getmsg(f, must_pass=True)
        
    def test_3_sub_2_or_False(self):
        "Asserts: True. Percent *is* evaled"
        def f():
            assert (3 - 2) or False
        getmsg(f, must_pass=True)
        
# end inserted code

tox-output.txt

$ tox -e py27 -- testing/test_assertrewrite_output.py -k TestAssertionRewriteCompoundAssertWithPercent -v
GLOB sdist-make: setup.py
py27 inst-nodeps: .tox/dist/pytest-2.7.0.dev1.zip
py27 runtests: PYTHONHASHSEED='2078814091'
py27 runtests: commands[0] | py.test --lsof -rfsxX --junitxml=.tox/py27/log/junit-py27.xml test_assertrewrite_output.py -k TestAssertionRewriteCompoundAssertWithPercent -v
===================================================================== test session starts =====================================================================
platform linux2 -- Python 2.7.6 -- py-1.4.26 -- pytest-2.7.0.dev1 -- .tox/py27/bin/python2.7
collected 32 items 

test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_and_3_mod_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_and_1_mod_1 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_and_1_mod_1 xfail
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_mod_1_and_True xfail
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_mod_2_and_False xfail
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_mod_1_and_False xfail
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_or_1_mod_1 xfail
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_mod_1_or_False xfail
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_or_3_mod_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_or_1_mod_1 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_and_3_mod_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_mod_2_and_True PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_or_3_mod_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_mod_2_or_True PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_mod_1_or_True PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_mod_2_or_False PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_and_3_sub_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_and_1_sub_1 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_and_1_sub_1 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_sub_1_and_True PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_sub_2_and_False PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_sub_1_and_False PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_or_1_sub_1 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_sub_1_or_False PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_or_3_sub_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_or_1_sub_1 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_True_and_3_sub_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_sub_2_and_True PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_False_or_3_sub_2 PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_sub_2_or_True PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_1_sub_1_or_True PASSED
test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::test_3_sub_2_or_False PASSED

-------------------- generated xml file: .tox/py27/log/junit-py27.xml ---------------------
=================================================================== short test summary info ===================================================================
XFAIL test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::()::test_True_and_1_mod_1
  reason: issue 615 - ValueError on compound assert with percent: ValueError("unsupported format character ')' (0x29) at index 16",)
XFAIL test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::()::test_1_mod_1_and_True
  reason: issue 615 - ValueError on compound assert with percent: ValueError("unsupported format character ')' (0x29) at index 7",)
XFAIL test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::()::test_3_mod_2_and_False
  reason: issue 615 - ValueError on compound assert with percent: ValueError("unsupported format character ')' (0x29) at index 7",)
XFAIL test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::()::test_1_mod_1_and_False
  reason: issue 615 - ValueError on compound assert with percent: ValueError("unsupported format character ')' (0x29) at index 7",)
XFAIL test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::()::test_False_or_1_mod_1
  reason: issue 615 - ValueError on compound assert with percent: ValueError("unsupported format character ')' (0x29) at index 16",)
XFAIL test_assertrewrite_output.py::TestAssertionRewriteCompoundAssertWithPercent::()::test_1_mod_1_or_False
  reason: issue 615 - ValueError on compound assert with percent: ValueError("unsupported format character ')' (0x29) at index 7",)
============================================================ 26 passed, 6 xfailed in 0.74 seconds =============================================================
___________________________________________________________________________ summary ___________________________________________________________________________
  py27: commands succeeded
  congratulations :)