/Lib/lib2to3/fixes/fix_itertools.py

 1""" Fixer for itertools.(imap|ifilter|izip) --> (map|filter|zip) and
 2    itertools.ifilterfalse --> itertools.filterfalse (bugs 2360-2363)
 3
 4    imports from itertools are fixed in fix_itertools_import.py
 5
 6    If itertools is imported as something else (ie: import itertools as it;
 7    it.izip(spam, eggs)) method calls will not get fixed.
 8    """
 9
10# Local imports
11from .. import fixer_base
12from ..fixer_util import Name
13
14class FixItertools(fixer_base.BaseFix):
15    it_funcs = "('imap'|'ifilter'|'izip'|'ifilterfalse')"
16    PATTERN = """
17              power< it='itertools'
18                  trailer<
19                     dot='.' func=%(it_funcs)s > trailer< '(' [any] ')' > >
20              |
21              power< func=%(it_funcs)s trailer< '(' [any] ')' > >
22              """ %(locals())
23
24    # Needs to be run after fix_(map|zip|filter)
25    run_order = 6
26
27    def transform(self, node, results):
28        prefix = None
29        func = results['func'][0]
30        if 'it' in results and func.value != 'ifilterfalse':
31            dot, it = (results['dot'], results['it'])
32            # Remove the 'itertools'
33            prefix = it.get_prefix()
34            it.remove()
35            # Replace the node wich contains ('.', 'function') with the
36            # function (to be consistant with the second part of the pattern)
37            dot.remove()
38            func.parent.replace(func)
39
40        prefix = prefix or func.get_prefix()
41        func.replace(Name(func.value[1:], prefix=prefix))