# These classes implement a doctest runner plugin for nose, a "known failure"
# error class, and a customized TestProgram for NumPy.

# Because this module imports nose directly, it should not
# be used except by nosetester.py to avoid a general NumPy
# dependency on nose.
from __future__ import division, absolute_import, print_function

import os
import doctest
import inspect

import numpy
import pytest
from .utils import KnownFailureException, SkipTest
import _pytest.runner
import _pytest.skipping


class NpyPlugin(object):
    
    def pytest_runtest_makereport(self, call):
        if call.excinfo:
            if call.excinfo.errisinstance(KnownFailureException):
                #let's substitute the excinfo with a pytest.xfail one
                call2 = call.__class__(
                    lambda: _pytest.runner.skip(str(call.excinfo.value)),
                    call.when)
                print()
                print()
                print(call.excinfo._getreprcrash())
                print()
                print(call.excinfo)
                print()
                print(call2.excinfo)
                print()
                call.excinfo = call2.excinfo
            if call.excinfo.errisinstance(SkipTest):
                #let's substitute the excinfo with a pytest.skip one
                call2 = call.__class__(
                    lambda: _pytest.runner.skip(str(call.excinfo.value)),
                    call.when)
                call.excinfo = call2.excinfo


if False:
    from nose.plugins import doctests as npd
    from nose.plugins.errorclass import ErrorClass, ErrorClassPlugin
    from nose.plugins.base import Plugin
    from nose.util import src
    from .nosetester import get_package_name
    # Some of the classes in this module begin with 'Numpy' to clearly distinguish
    # them from the plethora of very similar names from nose/unittest/doctest

    #-----------------------------------------------------------------------------
    # Modified version of the one in the stdlib, that fixes a python bug (doctests
    # not found in extension modules, http://bugs.python.org/issue3158)
    class NumpyDocTestFinder(doctest.DocTestFinder):

        def _from_module(self, module, object):
            """
            Return true if the given object is defined in the given
            module.
            """
            if module is None:
                return True
            elif inspect.isfunction(object):
                return module.__dict__ is object.__globals__
            elif inspect.isbuiltin(object):
                return module.__name__ == object.__module__
            elif inspect.isclass(object):
                return module.__name__ == object.__module__
            elif inspect.ismethod(object):
                # This one may be a bug in cython that fails to correctly set the
                # __module__ attribute of methods, but since the same error is easy
                # to make by extension code writers, having this safety in place
                # isn't such a bad idea
                return module.__name__ == object.__self__.__class__.__module__
            elif inspect.getmodule(object) is not None:
                return module is inspect.getmodule(object)
            elif hasattr(object, '__module__'):
                return module.__name__ == object.__module__
            elif isinstance(object, property):
                return True  # [XX] no way not be sure.
            else:
                raise ValueError("object must be a class or function")

        def _find(self, tests, obj, name, module, source_lines, globs, seen):
            """
            Find tests for the given object and any contained objects, and
            add them to `tests`.
            """

            doctest.DocTestFinder._find(self, tests, obj, name, module,
                                        source_lines, globs, seen)

            # Below we re-run pieces of the above method with manual modifications,
            # because the original code is buggy and fails to correctly identify
            # doctests in extension modules.

            # Local shorthands
            from inspect import (
                isroutine, isclass, ismodule, isfunction, ismethod
                )

            # Look for tests in a module's contained objects.
            if ismodule(obj) and self._recurse:
                for valname, val in obj.__dict__.items():
                    valname1 = '%s.%s' % (name, valname)
                    if ( (isroutine(val) or isclass(val))
                         and self._from_module(module, val)):

                        self._find(tests, val, valname1, module, source_lines,
                                   globs, seen)

            # Look for tests in a class's contained objects.
            if isclass(obj) and self._recurse:
                for valname, val in obj.__dict__.items():
                    # Special handling for staticmethod/classmethod.
                    if isinstance(val, staticmethod):
                        val = getattr(obj, valname)
                    if isinstance(val, classmethod):
                        val = getattr(obj, valname).__func__

                    # Recurse to methods, properties, and nested classes.
                    if ((isfunction(val) or isclass(val) or
                         ismethod(val) or isinstance(val, property)) and
                          self._from_module(module, val)):
                        valname = '%s.%s' % (name, valname)
                        self._find(tests, val, valname, module, source_lines,
                                   globs, seen)


    # second-chance checker; if the default comparison doesn't
    # pass, then see if the expected output string contains flags that
    # tell us to ignore the output
    class NumpyOutputChecker(doctest.OutputChecker):
        def check_output(self, want, got, optionflags):
            ret = doctest.OutputChecker.check_output(self, want, got,
                                                     optionflags)
            if not ret:
                if "#random" in want:
                    return True

                # it would be useful to normalize endianness so that
                # bigendian machines don't fail all the tests (and there are
                # actually some bigendian examples in the doctests). Let's try
                # making them all little endian
                got = got.replace("'>", "'<")
                want = want.replace("'>", "'<")

                # try to normalize out 32 and 64 bit default int sizes
                for sz in [4, 8]:
                    got = got.replace("'<i%d'" % sz, "int")
                    want = want.replace("'<i%d'" % sz, "int")

                ret = doctest.OutputChecker.check_output(self, want,
                        got, optionflags)

            return ret


    # Subclass nose.plugins.doctests.DocTestCase to work around a bug in
    # its constructor that blocks non-default arguments from being passed
    # down into doctest.DocTestCase
    class NumpyDocTestCase(npd.DocTestCase):
        def __init__(self, test, optionflags=0, setUp=None, tearDown=None,
                     checker=None, obj=None, result_var='_'):
            self._result_var = result_var
            self._nose_obj = obj
            doctest.DocTestCase.__init__(self, test,
                                         optionflags=optionflags,
                                         setUp=setUp, tearDown=tearDown,
                                         checker=checker)


    print_state = numpy.get_printoptions()

    class NumpyDoctest(npd.Doctest):
        name = 'numpydoctest'   # call nosetests with --with-numpydoctest
        score = 1000  # load late, after doctest builtin

        # always use whitespace and ellipsis options for doctests
        doctest_optflags = doctest.NORMALIZE_WHITESPACE | doctest.ELLIPSIS

        # files that should be ignored for doctests
        doctest_ignore = ['generate_numpy_api.py',
                          'setup.py']

        # Custom classes; class variables to allow subclassing
        doctest_case_class = NumpyDocTestCase
        out_check_class = NumpyOutputChecker
        test_finder_class = NumpyDocTestFinder

        # Don't use the standard doctest option handler; hard-code the option values
        def options(self, parser, env=os.environ):
            Plugin.options(self, parser, env)
            # Test doctests in 'test' files / directories. Standard plugin default
            # is False
            self.doctest_tests = True
            # Variable name; if defined, doctest results stored in this variable in
            # the top-level namespace.  None is the standard default
            self.doctest_result_var = None

        def configure(self, options, config):
            # parent method sets enabled flag from command line --with-numpydoctest
            Plugin.configure(self, options, config)
            self.finder = self.test_finder_class()
            self.parser = doctest.DocTestParser()
            if self.enabled:
                # Pull standard doctest out of plugin list; there's no reason to run
                # both.  In practice the Unplugger plugin above would cover us when
                # run from a standard numpy.test() call; this is just in case
                # someone wants to run our plugin outside the numpy.test() machinery
                config.plugins.plugins = [p for p in config.plugins.plugins
                                          if p.name != 'doctest']

        def set_test_context(self, test):
            """ Configure `test` object to set test context

            We set the numpy / scipy standard doctest namespace

            Parameters
            ----------
            test : test object
                with ``globs`` dictionary defining namespace

            Returns
            -------
            None

            Notes
            -----
            `test` object modified in place
            """
            # set the namespace for tests
            pkg_name = get_package_name(os.path.dirname(test.filename))

            # Each doctest should execute in an environment equivalent to
            # starting Python and executing "import numpy as np", and,
            # for SciPy packages, an additional import of the local
            # package (so that scipy.linalg.basic.py's doctests have an
            # implicit "from scipy import linalg" as well.
            #
            # Note: __file__ allows the doctest in NoseTester to run
            # without producing an error
            test.globs = {'__builtins__':__builtins__,
                          '__file__':'__main__',
                          '__name__':'__main__',
                          'np':numpy}
            # add appropriate scipy import for SciPy tests
            if 'scipy' in pkg_name:
                p = pkg_name.split('.')
                p2 = p[-1]
                test.globs[p2] = __import__(pkg_name, test.globs, {}, [p2])

        # Override test loading to customize test context (with set_test_context
        # method), set standard docstring options, and install our own test output
        # checker
        def loadTestsFromModule(self, module):
            if not self.matches(module.__name__):
                npd.log.debug("Doctest doesn't want module %s", module)
                return
            try:
                tests = self.finder.find(module)
            except AttributeError:
                # nose allows module.__test__ = False; doctest does not and
                # throws AttributeError
                return
            if not tests:
                return
            tests.sort()
            module_file = src(module.__file__)
            for test in tests:
                if not test.examples:
                    continue
                if not test.filename:
                    test.filename = module_file
                # Set test namespace; test altered in place
                self.set_test_context(test)
                yield self.doctest_case_class(test,
                                              optionflags=self.doctest_optflags,
                                              checker=self.out_check_class(),
                                              result_var=self.doctest_result_var)

        # Add an afterContext method to nose.plugins.doctests.Doctest in order
        # to restore print options to the original state after each doctest
        def afterContext(self):
            numpy.set_printoptions(**print_state)

        # Ignore NumPy-specific build files that shouldn't be searched for tests
        def wantFile(self, file):
            bn = os.path.basename(file)
            if bn in self.doctest_ignore:
                return False
            return npd.Doctest.wantFile(self, file)


    class Unplugger(object):
        """ Nose plugin to remove named plugin late in loading

        By default it removes the "doctest" plugin.
        """
        name = 'unplugger'
        enabled = True  # always enabled
        score = 4000  # load late in order to be after builtins

        def __init__(self, to_unplug='doctest'):
            self.to_unplug = to_unplug

        def options(self, parser, env):
            pass

        def configure(self, options, config):
            # Pull named plugin out of plugins list
            config.plugins.plugins = [p for p in config.plugins.plugins
                                      if p.name != self.to_unplug]



    # Class allows us to save the results of the tests in runTests - see runTests
    # method docstring for details
    class NumpyTestProgram(nose.core.TestProgram):
        def runTests(self):
            """Run Tests. Returns true on success, false on failure, and
            sets self.success to the same value.

            Because nose currently discards the test result object, but we need
            to return it to the user, override TestProgram.runTests to retain
            the result
            """
            if self.testRunner is None:
                self.testRunner = nose.core.TextTestRunner(stream=self.config.stream,
                                                           verbosity=self.config.verbosity,
                                                           config=self.config)
            plug_runner = self.config.plugins.prepareTestRunner(self.testRunner)
            if plug_runner is not None:
                self.testRunner = plug_runner
            self.result = self.testRunner.run(self.test)
            self.success = self.result.wasSuccessful()
            return self.success

