179 lines
6.1 KiB
Python
179 lines
6.1 KiB
Python
# Copyright 2006 Google, Inc. All Rights Reserved.
|
|
# Licensed to PSF under a Contributor Agreement.
|
|
|
|
"""Base class for fixers (optional, but recommended)."""
|
|
|
|
# Python imports
|
|
import logging
|
|
import itertools
|
|
|
|
# Local imports
|
|
from .patcomp import PatternCompiler
|
|
from . import pygram
|
|
from .fixer_util import does_tree_import
|
|
|
|
class BaseFix(object):
|
|
|
|
"""Optional base class for fixers.
|
|
|
|
The subclass name must be FixFooBar where FooBar is the result of
|
|
removing underscores and capitalizing the words of the fix name.
|
|
For example, the class name for a fixer named 'has_key' should be
|
|
FixHasKey.
|
|
"""
|
|
|
|
PATTERN = None # Most subclasses should override with a string literal
|
|
pattern = None # Compiled pattern, set by compile_pattern()
|
|
options = None # Options object passed to initializer
|
|
filename = None # The filename (set by set_filename)
|
|
logger = None # A logger (set by set_filename)
|
|
numbers = itertools.count(1) # For new_name()
|
|
used_names = set() # A set of all used NAMEs
|
|
order = "post" # Does the fixer prefer pre- or post-order traversal
|
|
explicit = False # Is this ignored by refactor.py -f all?
|
|
run_order = 5 # Fixers will be sorted by run order before execution
|
|
# Lower numbers will be run first.
|
|
|
|
# Shortcut for access to Python grammar symbols
|
|
syms = pygram.python_symbols
|
|
|
|
def __init__(self, options, log):
|
|
"""Initializer. Subclass may override.
|
|
|
|
Args:
|
|
options: an dict containing the options passed to RefactoringTool
|
|
that could be used to customize the fixer through the command line.
|
|
log: a list to append warnings and other messages to.
|
|
"""
|
|
self.options = options
|
|
self.log = log
|
|
self.compile_pattern()
|
|
|
|
def compile_pattern(self):
|
|
"""Compiles self.PATTERN into self.pattern.
|
|
|
|
Subclass may override if it doesn't want to use
|
|
self.{pattern,PATTERN} in .match().
|
|
"""
|
|
if self.PATTERN is not None:
|
|
self.pattern = PatternCompiler().compile_pattern(self.PATTERN)
|
|
|
|
def set_filename(self, filename):
|
|
"""Set the filename, and a logger derived from it.
|
|
|
|
The main refactoring tool should call this.
|
|
"""
|
|
self.filename = filename
|
|
self.logger = logging.getLogger(filename)
|
|
|
|
def match(self, node):
|
|
"""Returns match for a given parse tree node.
|
|
|
|
Should return a true or false object (not necessarily a bool).
|
|
It may return a non-empty dict of matching sub-nodes as
|
|
returned by a matching pattern.
|
|
|
|
Subclass may override.
|
|
"""
|
|
results = {"node": node}
|
|
return self.pattern.match(node, results) and results
|
|
|
|
def transform(self, node, results):
|
|
"""Returns the transformation for a given parse tree node.
|
|
|
|
Args:
|
|
node: the root of the parse tree that matched the fixer.
|
|
results: a dict mapping symbolic names to part of the match.
|
|
|
|
Returns:
|
|
None, or a node that is a modified copy of the
|
|
argument node. The node argument may also be modified in-place to
|
|
effect the same change.
|
|
|
|
Subclass *must* override.
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
def new_name(self, template=u"xxx_todo_changeme"):
|
|
"""Return a string suitable for use as an identifier
|
|
|
|
The new name is guaranteed not to conflict with other identifiers.
|
|
"""
|
|
name = template
|
|
while name in self.used_names:
|
|
name = template + unicode(self.numbers.next())
|
|
self.used_names.add(name)
|
|
return name
|
|
|
|
def log_message(self, message):
|
|
if self.first_log:
|
|
self.first_log = False
|
|
self.log.append("### In file %s ###" % self.filename)
|
|
self.log.append(message)
|
|
|
|
def cannot_convert(self, node, reason=None):
|
|
"""Warn the user that a given chunk of code is not valid Python 3,
|
|
but that it cannot be converted automatically.
|
|
|
|
First argument is the top-level node for the code in question.
|
|
Optional second argument is why it can't be converted.
|
|
"""
|
|
lineno = node.get_lineno()
|
|
for_output = node.clone()
|
|
for_output.set_prefix(u"")
|
|
msg = "Line %d: could not convert: %s"
|
|
self.log_message(msg % (lineno, for_output))
|
|
if reason:
|
|
self.log_message(reason)
|
|
|
|
def warning(self, node, reason):
|
|
"""Used for warning the user about possible uncertainty in the
|
|
translation.
|
|
|
|
First argument is the top-level node for the code in question.
|
|
Optional second argument is why it can't be converted.
|
|
"""
|
|
lineno = node.get_lineno()
|
|
self.log_message("Line %d: %s" % (lineno, reason))
|
|
|
|
def start_tree(self, tree, filename):
|
|
"""Some fixers need to maintain tree-wide state.
|
|
This method is called once, at the start of tree fix-up.
|
|
|
|
tree - the root node of the tree to be processed.
|
|
filename - the name of the file the tree came from.
|
|
"""
|
|
self.used_names = tree.used_names
|
|
self.set_filename(filename)
|
|
self.numbers = itertools.count(1)
|
|
self.first_log = True
|
|
|
|
def finish_tree(self, tree, filename):
|
|
"""Some fixers need to maintain tree-wide state.
|
|
This method is called once, at the conclusion of tree fix-up.
|
|
|
|
tree - the root node of the tree to be processed.
|
|
filename - the name of the file the tree came from.
|
|
"""
|
|
pass
|
|
|
|
|
|
class ConditionalFix(BaseFix):
|
|
""" Base class for fixers which not execute if an import is found. """
|
|
|
|
# This is the name of the import which, if found, will cause the test to be skipped
|
|
skip_on = None
|
|
|
|
def start_tree(self, *args):
|
|
super(ConditionalFix, self).start_tree(*args)
|
|
self._should_skip = None
|
|
|
|
def should_skip(self, node):
|
|
if self._should_skip is not None:
|
|
return self._should_skip
|
|
pkg = self.skip_on.split(".")
|
|
name = pkg[-1]
|
|
pkg = ".".join(pkg[:-1])
|
|
self._should_skip = does_tree_import(pkg, name, node)
|
|
return self._should_skip
|