cpython/Lib/lib2to3/fixes/fix_next.py
Benjamin Peterson 2c3ac6b875 Merged revisions 73370 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r73370 | benjamin.peterson | 2009-06-11 17:06:46 -0500 (Thu, 11 Jun 2009) | 105 lines

  Merged revisions 72523,72950-72951,72994,73003,73033,73036-73040,73091-73093,73096,73179-73181,73192,73231,73244,73255-73256,73365 via svnmerge from
  svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3

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    r72523 | benjamin.peterson | 2009-05-09 14:42:26 -0500 (Sat, 09 May 2009) | 1 line

    remove parenthesis
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    r72950 | benjamin.peterson | 2009-05-26 18:19:45 -0500 (Tue, 26 May 2009) | 1 line

    remove unused imports
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    r72951 | benjamin.peterson | 2009-05-26 18:27:00 -0500 (Tue, 26 May 2009) | 1 line

    this is no longer executable
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    r72994 | benjamin.peterson | 2009-05-28 15:32:54 -0500 (Thu, 28 May 2009) | 1 line

    fix test_all_fixers on Windows #6134
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    r73003 | benjamin.peterson | 2009-05-28 21:57:28 -0500 (Thu, 28 May 2009) | 4 lines

    make 2to3 test utilities easier to use with other applications (3to2)

    Patch by Joe Amenta
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    r73033 | benjamin.peterson | 2009-05-29 16:58:32 -0500 (Fri, 29 May 2009) | 1 line

    update grammar for multi with statement
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    r73036 | benjamin.peterson | 2009-05-29 17:33:20 -0500 (Fri, 29 May 2009) | 1 line

    simplify fix_unicode
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    r73037 | benjamin.peterson | 2009-05-29 17:53:03 -0500 (Fri, 29 May 2009) | 1 line

    add custom error for pattern syntax errors
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    r73038 | benjamin.peterson | 2009-05-29 17:55:00 -0500 (Fri, 29 May 2009) | 1 line

    complain if details are attached to a token
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    r73039 | benjamin.peterson | 2009-05-29 18:00:28 -0500 (Fri, 29 May 2009) | 1 line

    add a test for whitespace
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    r73040 | benjamin.peterson | 2009-05-29 18:01:17 -0500 (Fri, 29 May 2009) | 1 line

    a fix for emacs highlighting
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    r73091 | benjamin.peterson | 2009-05-31 20:55:25 -0500 (Sun, 31 May 2009) | 1 line

    deprecate set_prefix() and get_prefix() in favor of a prefix property
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    r73092 | benjamin.peterson | 2009-05-31 21:00:51 -0500 (Sun, 31 May 2009) | 1 line

    change hideous java naming scheme
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    r73093 | benjamin.peterson | 2009-05-31 21:01:39 -0500 (Sun, 31 May 2009) | 1 line

    remove dated comment
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    r73096 | benjamin.peterson | 2009-05-31 21:40:53 -0500 (Sun, 31 May 2009) | 1 line

    group tests
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    r73179 | benjamin.peterson | 2009-06-03 13:09:53 -0500 (Wed, 03 Jun 2009) | 1 line

    handle the case where there's multiple trailers #6185
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    r73180 | benjamin.peterson | 2009-06-03 13:18:05 -0500 (Wed, 03 Jun 2009) | 1 line

    scrap __main__ section
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    r73181 | benjamin.peterson | 2009-06-03 13:24:48 -0500 (Wed, 03 Jun 2009) | 1 line

    remove shebang lines and __main__ sections
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    r73192 | benjamin.peterson | 2009-06-03 19:16:30 -0500 (Wed, 03 Jun 2009) | 4 lines

    actually test something here

    Thanks to Joe Amenta for noticing.y
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    r73231 | benjamin.peterson | 2009-06-04 13:38:50 -0500 (Thu, 04 Jun 2009) | 1 line

    remove unused variable
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    r73244 | benjamin.peterson | 2009-06-05 08:39:25 -0500 (Fri, 05 Jun 2009) | 1 line

    allow fixers to give different options in setUp
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    r73255 | benjamin.peterson | 2009-06-06 11:23:46 -0500 (Sat, 06 Jun 2009) | 1 line

    fix the except fixer on one line suites #6222
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    r73256 | benjamin.peterson | 2009-06-06 11:27:40 -0500 (Sat, 06 Jun 2009) | 1 line

    test one-line else and finally clauses
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    r73365 | benjamin.peterson | 2009-06-11 17:01:32 -0500 (Thu, 11 Jun 2009) | 1 line

    normalize whitespace
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2009-06-11 23:47:38 +00:00

102 lines
3.1 KiB
Python

"""Fixer for it.next() -> next(it), per PEP 3114."""
# Author: Collin Winter
# Things that currently aren't covered:
# - listcomp "next" names aren't warned
# - "with" statement targets aren't checked
# Local imports
from ..pgen2 import token
from ..pygram import python_symbols as syms
from .. import fixer_base
from ..fixer_util import Name, Call, find_binding
bind_warning = "Calls to builtin next() possibly shadowed by global binding"
class FixNext(fixer_base.BaseFix):
PATTERN = """
power< base=any+ trailer< '.' attr='next' > trailer< '(' ')' > >
|
power< head=any+ trailer< '.' attr='next' > not trailer< '(' ')' > >
|
classdef< 'class' any+ ':'
suite< any*
funcdef< 'def'
name='next'
parameters< '(' NAME ')' > any+ >
any* > >
|
global=global_stmt< 'global' any* 'next' any* >
"""
order = "pre" # Pre-order tree traversal
def start_tree(self, tree, filename):
super(FixNext, self).start_tree(tree, filename)
n = find_binding('next', tree)
if n:
self.warning(n, bind_warning)
self.shadowed_next = True
else:
self.shadowed_next = False
def transform(self, node, results):
assert results
base = results.get("base")
attr = results.get("attr")
name = results.get("name")
if base:
if self.shadowed_next:
attr.replace(Name("__next__", prefix=attr.prefix))
else:
base = [n.clone() for n in base]
base[0].prefix = ""
node.replace(Call(Name("next", prefix=node.prefix), base))
elif name:
n = Name("__next__", prefix=name.prefix)
name.replace(n)
elif attr:
# We don't do this transformation if we're assigning to "x.next".
# Unfortunately, it doesn't seem possible to do this in PATTERN,
# so it's being done here.
if is_assign_target(node):
head = results["head"]
if "".join([str(n) for n in head]).strip() == '__builtin__':
self.warning(node, bind_warning)
return
attr.replace(Name("__next__"))
elif "global" in results:
self.warning(node, bind_warning)
self.shadowed_next = True
### The following functions help test if node is part of an assignment
### target.
def is_assign_target(node):
assign = find_assign(node)
if assign is None:
return False
for child in assign.children:
if child.type == token.EQUAL:
return False
elif is_subtree(child, node):
return True
return False
def find_assign(node):
if node.type == syms.expr_stmt:
return node
if node.type == syms.simple_stmt or node.parent is None:
return None
return find_assign(node.parent)
def is_subtree(root, node):
if root == node:
return True
return any([is_subtree(c, node) for c in root.children])