"""Test suite for 2to3's parser and grammar files.

This is the place to add tests for changes to 2to3's grammar, such as those
merging the grammars for Python 2 and 3. In addition to specific tests for
parts of the grammar we've changed, we also make sure we can parse the
test_grammar.py files from both Python 2 and Python 3.
"""

from __future__ import with_statement

# Testing imports
from . import support
from .support import driver, test_dir
from test import test_support


# Python imports
import binascii
import operator
import os
import pickle
import shutil
import subprocess
import sys
import tempfile
import types
import unittest

# Local imports
from lib2to3.pgen2 import driver as pgen2_driver
from lib2to3.pgen2 import tokenize
from ..pgen2.parse import ParseError
from lib2to3.pygram import python_symbols as syms


class TestDriver(support.TestCase):

    def test_formfeed(self):
        s = """print 1\n\x0Cprint 2\n"""
        t = driver.parse_string(s)
        self.assertEqual(t.children[0].children[0].type, syms.print_stmt)
        self.assertEqual(t.children[1].children[0].type, syms.print_stmt)


class TestPgen2Caching(support.TestCase):
    def test_load_grammar_from_txt_file(self):
        pgen2_driver.load_grammar(support.grammar_path, save=False, force=True)

    @unittest.skipIf(test_support.is_jython, "Not a valid test for Jython")
    def test_load_grammar_from_pickle(self):
        # Make a copy of the grammar file in a temp directory we are
        # guaranteed to be able to write to.
        tmpdir = tempfile.mkdtemp()
        try:
            grammar_copy = os.path.join(
                    tmpdir, os.path.basename(support.grammar_path))
            shutil.copy(support.grammar_path, grammar_copy)
            pickle_name = pgen2_driver._generate_pickle_name(grammar_copy)

            pgen2_driver.load_grammar(grammar_copy, save=True, force=True)
            self.assertTrue(os.path.exists(pickle_name))

            os.unlink(grammar_copy)  # Only the pickle remains...
            pgen2_driver.load_grammar(grammar_copy, save=False, force=False)
        finally:
            shutil.rmtree(tmpdir)

    @unittest.skipIf(test_support.is_jython, "Not a valid test for Jython")
    @unittest.skipIf(sys.executable is None, 'sys.executable required')
    def test_load_grammar_from_subprocess(self):
        tmpdir = tempfile.mkdtemp()
        tmpsubdir = os.path.join(tmpdir, 'subdir')
        try:
            os.mkdir(tmpsubdir)
            grammar_base = os.path.basename(support.grammar_path)
            grammar_copy = os.path.join(tmpdir, grammar_base)
            grammar_sub_copy = os.path.join(tmpsubdir, grammar_base)
            shutil.copy(support.grammar_path, grammar_copy)
            shutil.copy(support.grammar_path, grammar_sub_copy)
            pickle_name = pgen2_driver._generate_pickle_name(grammar_copy)
            pickle_sub_name = pgen2_driver._generate_pickle_name(
                     grammar_sub_copy)
            self.assertNotEqual(pickle_name, pickle_sub_name)

            # Generate a pickle file from this process.
            pgen2_driver.load_grammar(grammar_copy, save=True, force=True)
            self.assertTrue(os.path.exists(pickle_name))

            # Generate a new pickle file in a subprocess with a most likely
            # different hash randomization seed.
            sub_env = dict(os.environ)
            sub_env['PYTHONHASHSEED'] = 'random'
            subprocess.check_call(
                    [sys.executable, '-c', """
from lib2to3.pgen2 import driver as pgen2_driver
pgen2_driver.load_grammar(%r, save=True, force=True)
                    """ % (grammar_sub_copy,)],
                    env=sub_env)
            self.assertTrue(os.path.exists(pickle_sub_name))

            with open(pickle_name, 'rb') as pickle_f_1, \
                    open(pickle_sub_name, 'rb') as pickle_f_2:
                self.assertEqual(
                    pickle_f_1.read(), pickle_f_2.read(),
                    msg='Grammar caches generated using different hash seeds'
                    ' were not identical.')
        finally:
            shutil.rmtree(tmpdir)

    @unittest.skipIf(test_support.is_jython, "Not a valid test for Jython")
    def test_load_packaged_grammar(self):
        modname = __name__ + '.load_test'
        class MyLoader:
            def get_data(self, where):
                return pickle.dumps({'elephant': 19})
        class MyModule(types.ModuleType):
            __file__ = 'parsertestmodule'
            __loader__ = MyLoader()
        sys.modules[modname] = MyModule(modname)
        self.addCleanup(operator.delitem, sys.modules, modname)
        g = pgen2_driver.load_packaged_grammar(modname, 'Grammar.txt')
        self.assertEqual(g.elephant, 19)


class GrammarTest(support.TestCase):
    def validate(self, code):
        support.parse_string(code)

    def invalid_syntax(self, code):
        try:
            self.validate(code)
        except ParseError:
            pass
        else:
            raise AssertionError("Syntax shouldn't have been valid")


class TestMatrixMultiplication(GrammarTest):
    @unittest.skipIf(test_support.is_jython, "Not supported yet")
    def test_matrix_multiplication_operator(self):
        self.validate("a @ b")
        self.validate("a @= b")


class TestYieldFrom(GrammarTest):
    @unittest.skipIf(test_support.is_jython, "Not supported yet")
    def test_matrix_multiplication_operator(self):
        self.validate("yield from x")
        self.validate("(yield from x) + y")
        self.invalid_syntax("yield from")


class TestRaiseChanges(GrammarTest):
    def test_2x_style_1(self):
        self.validate("raise")

    def test_2x_style_2(self):
        self.validate("raise E, V")

    def test_2x_style_3(self):
        self.validate("raise E, V, T")

    def test_2x_style_invalid_1(self):
        self.invalid_syntax("raise E, V, T, Z")

    def test_3x_style(self):
        self.validate("raise E1 from E2")

    def test_3x_style_invalid_1(self):
        self.invalid_syntax("raise E, V from E1")

    def test_3x_style_invalid_2(self):
        self.invalid_syntax("raise E from E1, E2")

    def test_3x_style_invalid_3(self):
        self.invalid_syntax("raise from E1, E2")

    def test_3x_style_invalid_4(self):
        self.invalid_syntax("raise E from")

# Modelled after Lib/test/test_grammar.py:TokenTests.test_funcdef issue2292
# and Lib/test/text_parser.py test_list_displays, test_set_displays,
# test_dict_displays, test_argument_unpacking, ... changes.
class TestUnpackingGeneralizations(GrammarTest):
    def test_mid_positional_star(self):
        self.validate("""func(1, *(2, 3), 4)""")

    def test_double_star_dict_literal(self):
        self.validate("""func(**{'eggs':'scrambled', 'spam':'fried'})""")

    def test_double_star_dict_literal_after_keywords(self):
        self.validate("""func(spam='fried', **{'eggs':'scrambled'})""")

    def test_list_display(self):
        self.validate("""[*{2}, 3, *[4]]""")

    @unittest.skipIf(test_support.is_jython, "No Jython support yet")
    def test_set_display(self):
        self.validate("""{*{2}, 3, *[4]}""")

    @unittest.skipIf(test_support.is_jython, "No Jython support yet")
    def test_dict_display_1(self):
        self.validate("""{**{}}""")

    @unittest.skipIf(test_support.is_jython, "No Jython support yet")
    def test_dict_display_2(self):
        self.validate("""{**{}, 3:4, **{5:6, 7:8}}""")

    @unittest.skipIf(test_support.is_jython, "No Jython support yet")
    def test_argument_unpacking_1(self):
        self.validate("""f(a, *b, *c, d)""")

    @unittest.skipIf(test_support.is_jython, "No Jython support yet")
    def test_argument_unpacking_2(self):
        self.validate("""f(**a, **b)""")

    @unittest.skipIf(test_support.is_jython, "No Jython support yet")
    def test_argument_unpacking_3(self):
        self.validate("""f(2, *a, *b, **b, **c, **d)""")


# Adaptated from Python 3's Lib/test/test_grammar.py:GrammarTests.testFuncdef
class TestFunctionAnnotations(GrammarTest):
    def test_1(self):
        self.validate("""def f(x) -> list: pass""")

    def test_2(self):
        self.validate("""def f(x:int): pass""")

    def test_3(self):
        self.validate("""def f(*x:str): pass""")

    def test_4(self):
        self.validate("""def f(**x:float): pass""")

    def test_5(self):
        self.validate("""def f(x, y:1+2): pass""")

    def test_6(self):
        self.validate("""def f(a, (b:1, c:2, d)): pass""")

    def test_7(self):
        self.validate("""def f(a, (b:1, c:2, d), e:3=4, f=5, *g:6): pass""")

    def test_8(self):
        s = """def f(a, (b:1, c:2, d), e:3=4, f=5,
                        *g:6, h:7, i=8, j:9=10, **k:11) -> 12: pass"""
        self.validate(s)


class TestExcept(GrammarTest):
    def test_new(self):
        s = """
            try:
                x
            except E as N:
                y"""
        self.validate(s)

    def test_old(self):
        s = """
            try:
                x
            except E, N:
                y"""
        self.validate(s)


# Adapted from Python 3's Lib/test/test_grammar.py:GrammarTests.testAtoms
class TestSetLiteral(GrammarTest):
    def test_1(self):
        self.validate("""x = {'one'}""")

    def test_2(self):
        self.validate("""x = {'one', 1,}""")

    def test_3(self):
        self.validate("""x = {'one', 'two', 'three'}""")

    def test_4(self):
        self.validate("""x = {2, 3, 4,}""")


class TestNumericLiterals(GrammarTest):
    def test_new_octal_notation(self):
        self.validate("""0o7777777777777""")
        self.invalid_syntax("""0o7324528887""")

    def test_new_binary_notation(self):
        self.validate("""0b101010""")
        self.invalid_syntax("""0b0101021""")


class TestClassDef(GrammarTest):
    def test_new_syntax(self):
        self.validate("class B(t=7): pass")
        self.validate("class B(t, *args): pass")
        self.validate("class B(t, **kwargs): pass")
        self.validate("class B(t, *args, **kwargs): pass")
        self.validate("class B(t, y=9, *args, **kwargs): pass")


class TestParserIdempotency(support.TestCase):

    """A cut-down version of pytree_idempotency.py."""

    def test_all_project_files(self):
        for filepath in support.all_project_files():
            with open(filepath, "rb") as fp:
                encoding = tokenize.detect_encoding(fp.readline)[0]
            self.assertIsNotNone(encoding,
                                 "can't detect encoding for %s" % filepath)
            with open(filepath, "r") as fp:
                source = fp.read()
                source = source.decode(encoding)
            tree = driver.parse_string(source)
            new = unicode(tree)
            diffResult = diff(filepath, new, encoding)
            if diffResult:
                self.fail("Idempotency failed: {} using {} encoding\n{}".
                        format(filepath,encoding,diffResult) )

    def test_extended_unpacking(self):
        driver.parse_string("a, *b, c = x\n")
        driver.parse_string("[*a, b] = x\n")
        driver.parse_string("(z, *y, w) = m\n")
        driver.parse_string("for *z, m in d: pass\n")


class TestLiterals(GrammarTest):

    def validate(self, s):
        driver.parse_string(support.dedent(s) + "\n\n")

    def test_multiline_bytes_literals(self):
        s = """
            md5test(b"\xaa" * 80,
                    (b"Test Using Larger Than Block-Size Key "
                     b"and Larger Than One Block-Size Data"),
                    "6f630fad67cda0ee1fb1f562db3aa53e")
            """
        self.validate(s)

    def test_multiline_bytes_tripquote_literals(self):
        s = '''
            b"""
            <?xml version="1.0" encoding="UTF-8"?>
            <!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN">
            """
            '''
        self.validate(s)

    def test_multiline_str_literals(self):
        s = """
            md5test("\xaa" * 80,
                    ("Test Using Larger Than Block-Size Key "
                     "and Larger Than One Block-Size Data"),
                    "6f630fad67cda0ee1fb1f562db3aa53e")
            """
        self.validate(s)



def diff(fn, result, encoding):
    """Diff the result and original file content independent of OS. This 
    implementation is in Jython only. CPython 2.x calls out to the shell diff
    command. CPython 3.x str equality behaviour is simpler and should allow
    this test file to be replaced wholesale in Jython 3.x."""
    r = iter(result.encode(encoding).splitlines(True))
    lineNumber = 0
    with open(fn, "rbU") as f:
        for line in f:
            lineNumber += 1
            rline = next(r)
            if rline != line:
                return "original line {}:\n{}\n differs from:\n{}\n{}". \
                       format(lineNumber, line, rline, diffLine(line, rline) )
    return False

def diffLine(orig,result):
    charNumber = 0
    for c in orig:
        if c != result[charNumber]:
            return "Lines differ at char {}: {} vs {} (of {} vs {})".format(
                    charNumber,
                    binascii.hexlify(c),
                    binascii.hexlify(result[charNumber]),
                    len(orig),
                    len(result) )
        charNumber += 1


