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"""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 lib2to3.fixes.fix_imports import alternates, FixImports
from lib2to3 import fixer_base
from lib2to3.fixer_util import (Name, Comma, FromImport, Newline,
find_indentation, Node, syms)
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["members"]
for member in members:
# we only care about the actual members
if member.type == syms.import_as_name:
as_name = member.children[2].value
member_name = member.children[0].value
else:
member_name = member.value
as_name = None
if member_name != u",":
for change in MAPPING[mod_member.value]:
if member_name in change[1]:
if change[0] not in mod_dict:
modules.append(change[0])
mod_dict.setdefault(change[0], []).append(member)
new_nodes = []
indentation = find_indentation(node)
first = True
def handle_name(name, prefix):
if name.type == syms.import_as_name:
kids = [Name(name.children[0].value, prefix=prefix),
name.children[1].clone(),
name.children[2].clone()]
return [Node(syms.import_as_name, kids)]
return [Name(name.value, prefix=prefix)]
for module in modules:
elts = mod_dict[module]
names = []
for elt in elts[:-1]:
names.extend(handle_name(elt, pref))
names.append(Comma())
names.extend(handle_name(elts[-1], pref))
new = FromImport(module, names)
if not first or node.parent.prefix.endswith(indentation):
new.prefix = indentation
new_nodes.append(new)
first = False
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")
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