from lepl.matchers.variables import TraceVariables
from lepl.lexer.matchers import Token
from lepl.support.list import List

# The contents of this file are subject to the Mozilla Public License
# (MPL) Version 1.1 (the "License"); you may not use this file except
# in compliance with the License. You may obtain a copy of the License
# at http://www.mozilla.org/MPL/
#
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# basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
# the License for the specific language governing rights and
# limitations under the License.
#
# The Original Code is LEPL (http://www.acooke.org/lepl)
# The Initial Developer of the Original Code is Andrew Cooke.
# Portions created by the Initial Developer are Copyright (C) 2009-2010
# Andrew Cooke (andrew@acooke.org). All Rights Reserved.
#
# Alternatively, the contents of this file may be used under the terms
# of the LGPL license (the GNU Lesser General Public License,
# http://www.gnu.org/licenses/lgpl.html), in which case the provisions
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'''
Tests for cloning matchers.
'''

from unittest import TestCase
from difflib import Differ

from lepl.matchers.core import Literal, Delayed
from lepl.matchers.derived import Drop, UnsignedReal, Optional
from lepl.core.rewriters import clone_matcher


class CloneTest(TestCase):
    
    def assert_clone_ok(self, matcher):
        copy = clone_matcher(matcher)
        mtree = matcher.tree()
        ctree = copy.tree()
        if mtree != ctree:
            print(mtree)
            print(ctree)
            diff = Differ()
            print('\n'.join(diff.compare(mtree.split('\n'), ctree.split('\n'))))
        assert mtree == ctree
        assert matcher is not copy

    def test_single(self):
        self.assert_clone_ok(Literal('foo'))

    def test_no_loop(self):
        self.assert_clone_ok(Literal('a') | 'b' & Drop('c'))
        
    def test_delayed(self):
        d = Delayed()
        d += Literal('foo')
        self.assert_clone_ok(d)
        self.assert_clone_ok(Literal('bar') & d)
    
    def test_loop(self):
        d = Delayed()
        a = d | 'b'
        d += a
        self.assert_clone_ok(d)
        
    def test_loops(self):
        with TraceVariables():
            value = Token(UnsignedReal())
            symbol = Token('[^0-9a-zA-Z \t\r\n]')
            number = (Optional(symbol('-')) + value) >> float
            group2, group3c = Delayed(), Delayed()
    
            parens = symbol('(') & group3c & symbol(')')
            group1 = parens | number
    
            mul = (group2 & symbol('*') & group2) > List     # changed
            div = (group2 & symbol('/') & group2) > List     # changed
            group2 += (mul | div | group1)
    
            add = (group3c & symbol('+') & group3c) > List   # changed
            sub = (group3c & symbol('-') & group3c) > List   # changed
            group3c += (add | sub | group2)
        self.assert_clone_ok(group3c)