"""pytest configuration

Extends output capture as needed by pybind11: ignore constructors, optional unordered lines.

Adds docstring and exceptions message sanitizers: ignore Python 2 vs 3 differences.

"""

import pytest

import textwrap

import difflib

import re

import sys

import contextlib

import platform

import gc

_unicode_marker = re.compile(r'u(\'[^\']*\')')

_long_marker = re.compile(r'([0-9])L')

_hexadecimal = re.compile(r'0x[0-9a-fA-F]+')

# test_async.py requires support for async and await

collect_ignore = []

if sys.version_info[:2] < (3, 5):

    collect_ignore.append("test_async.py")

def _strip_and_dedent(s):

    """For triple-quote strings"""

    return textwrap.dedent(s.lstrip('\n').rstrip())

def _split_and_sort(s):

    """For output which does not require specific line order"""

    return sorted(_strip_and_dedent(s).splitlines())

def _make_explanation(a, b):

    """Explanation for a failed assert -- the a and b arguments are List[str]"""

    return ["--- actual / +++ expected"] + [line.strip('\n') for line in difflib.ndiff(a, b)]

class Output(object):

    """Basic output post-processing and comparison"""

    def __init__(self, string):

        self.string = string

        self.explanation = []

    def __str__(self):

        return self.string

    def __eq__(self, other):

        # Ignore constructor/destructor output which is prefixed with "###"

        a = [line for line in self.string.strip().splitlines() if not line.startswith("###")]

        b = _strip_and_dedent(other).splitlines()

        if a == b:

            return True

        else:

            self.explanation = _make_explanation(a, b)

            return False

class Unordered(Output):

    """Custom comparison for output without strict line ordering"""

    def __eq__(self, other):

        a = _split_and_sort(self.string)

        b = _split_and_sort(other)

        if a == b:

            return True

        else:

            self.explanation = _make_explanation(a, b)

            return False

class Capture(object):

    def __init__(self, capfd):

        self.capfd = capfd

        self.out = ""

        self.err = ""

    def __enter__(self):

        self.capfd.readouterr()

        return self

    def __exit__(self, *args):

        self.out, self.err = self.capfd.readouterr()

    def __eq__(self, other):

        a = Output(self.out)

        b = other

        if a == b:

            return True

        else:

            self.explanation = a.explanation

            return False

    def __str__(self):

        return self.out

    def __contains__(self, item):

        return item in self.out

    @property

    def unordered(self):

        return Unordered(self.out)

    @property

    def stderr(self):

        return Output(self.err)

@pytest.fixture

def capture(capsys):

    """Extended `capsys` with context manager and custom equality operators"""

    return Capture(capsys)

class SanitizedString(object):

    def __init__(self, sanitizer):

        self.sanitizer = sanitizer

        self.string = ""

        self.explanation = []

    def __call__(self, thing):

        self.string = self.sanitizer(thing)

        return self

    def __eq__(self, other):

        a = self.string

        b = _strip_and_dedent(other)

        if a == b:

            return True

        else:

            self.explanation = _make_explanation(a.splitlines(), b.splitlines())

            return False

def _sanitize_general(s):

    s = s.strip()

    s = s.replace("pybind11_tests.", "m.")

    s = s.replace("unicode", "str")

    s = _long_marker.sub(r"\1", s)

    s = _unicode_marker.sub(r"\1", s)

    return s

def _sanitize_docstring(thing):

    s = thing.__doc__

    s = _sanitize_general(s)

    return s

@pytest.fixture

def doc():

    """Sanitize docstrings and add custom failure explanation"""

    return SanitizedString(_sanitize_docstring)

def _sanitize_message(thing):

    s = str(thing)

    s = _sanitize_general(s)

    s = _hexadecimal.sub("0", s)

    return s

@pytest.fixture

def msg():

    """Sanitize messages and add custom failure explanation"""

    return SanitizedString(_sanitize_message)

# noinspection PyUnusedLocal

def pytest_assertrepr_compare(op, left, right):

    """Hook to insert custom failure explanation"""

    if hasattr(left, 'explanation'):

        return left.explanation

@contextlib.contextmanager

def suppress(exception):

    """Suppress the desired exception"""

    try:

        yield

    except exception:

        pass

def gc_collect():

    ''' Run the garbage collector twice (needed when running

    reference counting tests with PyPy) '''

    gc.collect()

    gc.collect()

def pytest_configure():

    """Add import suppression and test requirements to `pytest` namespace"""

    try:

        import numpy as np

    except ImportError:

        np = None

    try:

        import scipy

    except ImportError:

        scipy = None

    try:

        from pybind11_tests.eigen import have_eigen

    except ImportError:

        have_eigen = False

    pypy = platform.python_implementation() == "PyPy"

    skipif = pytest.mark.skipif

    pytest.suppress = suppress

    pytest.requires_numpy = skipif(not np, reason="numpy is not installed")

    pytest.requires_scipy = skipif(not np, reason="scipy is not installed")

    pytest.requires_eigen_and_numpy = skipif(not have_eigen or not np,

                                             reason="eigen and/or numpy are not installed")

    pytest.requires_eigen_and_scipy = skipif(

        not have_eigen or not scipy, reason="eigen and/or scipy are not installed")

    pytest.unsupported_on_pypy = skipif(pypy, reason="unsupported on PyPy")

    pytest.unsupported_on_py2 = skipif(sys.version_info.major < 3,

                                       reason="unsupported on Python 2.x")

    pytest.gc_collect = gc_collect

def _test_import_pybind11():

    """Early diagnostic for test module initialization errors

    When there is an error during initialization, the first import will report the

    real error while all subsequent imports will report nonsense. This import test

    is done early (in the pytest configuration file, before any tests) in order to

    avoid the noise of having all tests fail with identical error messages.

    Any possible exception is caught here and reported manually *without* the stack

    trace. This further reduces noise since the trace would only show pytest internals

    which are not useful for debugging pybind11 module issues.

    """

    # noinspection PyBroadException

    try:

        import pybind11_tests  # noqa: F401 imported but unused

    except Exception as e:

        print("Failed to import pybind11_tests from pytest:")

        print("  {}: {}".format(type(e).__name__, e))

        sys.exit(1)

_test_import_pybind11()