cpython/Lib/lib2to3/fixes/fix_urllib.py

181 lines
7.3 KiB
Python

"""Fix changes imports of urllib which are now incompatible.
This is rather similar to fix_imports, but because of the more
complex nature of the fixing for urllib, it has its own fixer.
"""
# Author: Nick Edds
# Local imports
from .fix_imports import alternates, FixImports
from .. import fixer_base
from ..fixer_util import Name, Comma, FromImport, Newline, attr_chain
MAPPING = {'urllib': [
('urllib.request',
['URLOpener', 'FancyURLOpener', 'urlretrieve',
'_urlopener', 'urlopen', 'urlcleanup',
'pathname2url', 'url2pathname']),
('urllib.parse',
['quote', 'quote_plus', 'unquote', 'unquote_plus',
'urlencode', 'splitattr', 'splithost', 'splitnport',
'splitpasswd', 'splitport', 'splitquery', 'splittag',
'splittype', 'splituser', 'splitvalue', ]),
('urllib.error',
['ContentTooShortError'])],
'urllib2' : [
('urllib.request',
['urlopen', 'install_opener', 'build_opener',
'Request', 'OpenerDirector', 'BaseHandler',
'HTTPDefaultErrorHandler', 'HTTPRedirectHandler',
'HTTPCookieProcessor', 'ProxyHandler',
'HTTPPasswordMgr',
'HTTPPasswordMgrWithDefaultRealm',
'AbstractBasicAuthHandler',
'HTTPBasicAuthHandler', 'ProxyBasicAuthHandler',
'AbstractDigestAuthHandler',
'HTTPDigestAuthHandler', 'ProxyDigestAuthHandler',
'HTTPHandler', 'HTTPSHandler', 'FileHandler',
'FTPHandler', 'CacheFTPHandler',
'UnknownHandler']),
('urllib.error',
['URLError', 'HTTPError']),
]
}
# Duplicate the url parsing functions for urllib2.
MAPPING["urllib2"].append(MAPPING["urllib"][1])
def build_pattern():
bare = set()
for old_module, changes in MAPPING.items():
for change in changes:
new_module, members = change
members = alternates(members)
yield """import_name< 'import' (module=%r
| dotted_as_names< any* module=%r any* >) >
""" % (old_module, old_module)
yield """import_from< 'from' mod_member=%r 'import'
( member=%s | import_as_name< member=%s 'as' any > |
import_as_names< members=any* >) >
""" % (old_module, members, members)
yield """import_from< 'from' module_star=%r 'import' star='*' >
""" % old_module
yield """import_name< 'import'
dotted_as_name< module_as=%r 'as' any > >
""" % old_module
# bare_with_attr has a special significance for FixImports.match().
yield """power< bare_with_attr=%r trailer< '.' member=%s > any* >
""" % (old_module, members)
class FixUrllib(FixImports):
def build_pattern(self):
return "|".join(build_pattern())
def transform_import(self, node, results):
"""Transform for the basic import case. Replaces the old
import name with a comma separated list of its
replacements.
"""
import_mod = results.get('module')
pref = import_mod.prefix
names = []
# create a Node list of the replacement modules
for name in MAPPING[import_mod.value][:-1]:
names.extend([Name(name[0], prefix=pref), Comma()])
names.append(Name(MAPPING[import_mod.value][-1][0], prefix=pref))
import_mod.replace(names)
def transform_member(self, node, results):
"""Transform for imports of specific module elements. Replaces
the module to be imported from with the appropriate new
module.
"""
mod_member = results.get('mod_member')
pref = mod_member.prefix
member = results.get('member')
# Simple case with only a single member being imported
if member:
# this may be a list of length one, or just a node
if isinstance(member, list):
member = member[0]
new_name = None
for change in MAPPING[mod_member.value]:
if member.value in change[1]:
new_name = change[0]
break
if new_name:
mod_member.replace(Name(new_name, prefix=pref))
else:
self.cannot_convert(node,
'This is an invalid module element')
# Multiple members being imported
else:
# a dictionary for replacements, order matters
modules = []
mod_dict = {}
members = results.get('members')
for member in members:
member = member.value
# we only care about the actual members
if member != ',':
for change in MAPPING[mod_member.value]:
if member in change[1]:
if change[0] in mod_dict:
mod_dict[change[0]].append(member)
else:
mod_dict[change[0]] = [member]
modules.append(change[0])
new_nodes = []
for module in modules:
elts = mod_dict[module]
names = []
for elt in elts[:-1]:
names.extend([Name(elt, prefix=pref), Comma()])
names.append(Name(elts[-1], prefix=pref))
new_nodes.append(FromImport(module, names))
if new_nodes:
nodes = []
for new_node in new_nodes[:-1]:
nodes.extend([new_node, Newline()])
nodes.append(new_nodes[-1])
node.replace(nodes)
else:
self.cannot_convert(node, 'All module elements are invalid')
def transform_dot(self, node, results):
"""Transform for calls to module members in code."""
module_dot = results.get('bare_with_attr')
member = results.get('member')
new_name = None
if isinstance(member, list):
member = member[0]
for change in MAPPING[module_dot.value]:
if member.value in change[1]:
new_name = change[0]
break
if new_name:
module_dot.replace(Name(new_name,
prefix=module_dot.prefix))
else:
self.cannot_convert(node, 'This is an invalid module element')
def transform(self, node, results):
if results.get('module'):
self.transform_import(node, results)
elif results.get('mod_member'):
self.transform_member(node, results)
elif results.get('bare_with_attr'):
self.transform_dot(node, results)
# Renaming and star imports are not supported for these modules.
elif results.get('module_star'):
self.cannot_convert(node, 'Cannot handle star imports.')
elif results.get('module_as'):
self.cannot_convert(node, 'This module is now multiple modules')