[Python-checkins] r56146 - in sandbox/trunk/2to3: example.py fixes/fix_filter.py fixes/fix_map.py fixes/util.py tests/test_fixers.py
guido.van.rossum
python-checkins at python.org
Mon Jul 2 15:20:43 CEST 2007
Author: guido.van.rossum
Date: Mon Jul 2 15:20:43 2007
New Revision: 56146
Added:
sandbox/trunk/2to3/fixes/fix_filter.py (contents, props changed)
sandbox/trunk/2to3/fixes/fix_map.py (contents, props changed)
Modified:
sandbox/trunk/2to3/example.py
sandbox/trunk/2to3/fixes/util.py
sandbox/trunk/2to3/tests/test_fixers.py
Log:
Add fixers for map and filter. Not perfect, but a start.
Modified: sandbox/trunk/2to3/example.py
==============================================================================
--- sandbox/trunk/2to3/example.py (original)
+++ sandbox/trunk/2to3/example.py Mon Jul 2 15:20:43 2007
@@ -344,4 +344,17 @@
a = raw_input()
b = raw_input(a.rstrip())
+def filter_examples():
+ filter(os.unlink, filenames)
+ filter(None, "whatever")
+ filter(lambda x: not x, range(4))
+
+def map_examples():
+ map(None, foo.bar)
+ map(None, foo.bar,)
+ map(None, foo, bar)
+ map(f, foo.bar)
+ map(lambda x: x+1, range(10))
+
+
# This is the last line.
Added: sandbox/trunk/2to3/fixes/fix_filter.py
==============================================================================
--- (empty file)
+++ sandbox/trunk/2to3/fixes/fix_filter.py Mon Jul 2 15:20:43 2007
@@ -0,0 +1,107 @@
+# Copyright 2007 Google, Inc. All Rights Reserved.
+# Licensed to PSF under a Contributor Agreement.
+
+"""Fixer that changes filter(F, X) into list(filter(F, X)).
+
+We avoid the transformation if the filter() call is directly contained
+in iter(<>), list(<>), tuple(<>), sorted(<>), ...join(<>), or
+for V in <>:.
+
+NOTE: This is still not correct if the original code was depending on
+filter(F, X) to return a string if X is a string and a tuple if X is a
+tuple. That would require type inference, which we don't do. Let
+Python 2.6 figure it out.
+"""
+
+# Local imports
+import pytree
+import patcomp
+from pgen2 import token
+from fixes import basefix
+from fixes.util import Name, Call, ListComp
+
+class FixFilter(basefix.BaseFix):
+
+ PATTERN = """
+ filter_lambda=power<
+ 'filter'
+ trailer<
+ '('
+ arglist<
+ lambdef< 'lambda' fp=NAME ':' xp=any >
+ ','
+ it=any
+ >
+ ')'
+ >
+ >
+ |
+ power<
+ 'filter'
+ args=trailer< '(' [any] ')' >
+ >
+ """
+
+ def transform(self, node):
+ results = self.match(node)
+ if "filter_lambda" in results:
+ new = ListComp(results.get("fp").clone(),
+ results.get("fp").clone(),
+ results.get("it").clone(),
+ results.get("xp").clone())
+ else:
+ if self.in_special_context(node):
+ return None
+ new = node.clone()
+ new.set_prefix("")
+ new = Call(Name("list"), [new])
+ new.set_prefix(node.get_prefix())
+ return new
+
+ P0 = """for_stmt< 'for' any 'in' node=any ':' any* >
+ | list_for< 'for' any 'in' node=any any* >
+ | gen_for< 'for' any 'in' node=any any* >
+ """
+ p0 = patcomp.PatternCompiler().compile_pattern(P0)
+
+ P1 = """
+ power<
+ NAME< 'iter' | 'list' | 'tuple' | 'sorted' >
+ trailer< '(' node=any ')' >
+ any*
+ >
+ """
+ p1 = patcomp.PatternCompiler().compile_pattern(P1)
+
+ P2 = """
+ power<
+ 'sorted'
+ trailer< '(' arglist<node=any any*> ')' >
+ any*
+ >
+ """
+ p2 = patcomp.PatternCompiler().compile_pattern(P2)
+
+ def in_special_context(self, node):
+ p = node.parent
+ if p is None:
+ return False
+ results = {}
+ if self.p0.match(p, results) and results["node"] is node:
+ return True
+
+ pp = p.parent
+ if pp is None:
+ return False
+ results = {}
+ if self.p1.match(pp, results) and results["node"] is node:
+ return True
+
+ ppp = pp.parent
+ if ppp is None:
+ return False
+ results = {}
+ if self.p2.match(ppp, results) and results["node"] is node:
+ return True
+
+ return False
Added: sandbox/trunk/2to3/fixes/fix_map.py
==============================================================================
--- (empty file)
+++ sandbox/trunk/2to3/fixes/fix_map.py Mon Jul 2 15:20:43 2007
@@ -0,0 +1,119 @@
+# Copyright 2007 Google, Inc. All Rights Reserved.
+# Licensed to PSF under a Contributor Agreement.
+
+"""Fixer that changes map(F, ...) into list(map(F, ...)).
+
+As a special case, map(None, X) is changed into list(X). (This is
+necessary because the semantics are changed in this case -- the new
+map(None, X) is equivalent to [(x,) for x in X].)
+
+We avoid the transformation (except for the special case mentioned
+above) if the map() call is directly contained in iter(<>), list(<>),
+tuple(<>), sorted(<>), ...join(<>), or for V in <>:.
+
+NOTE: This is still not correct if the original code was depending on
+map(F, X, Y, ...) to go on until the longest argument is exhausted,
+substituting None for missing values -- like zip(), it now stops as
+soon as the shortest argument is exhausted.
+"""
+
+# Local imports
+import pytree
+import patcomp
+from pgen2 import token
+from fixes import basefix
+from fixes.util import Name, Call, ListComp
+from pygram import python_symbols as syms
+
+class FixMap(basefix.BaseFix):
+
+ PATTERN = """
+ map_none=power<
+ 'map'
+ trailer< '(' arglist< 'None' ',' arg=any [','] > ')' >
+ >
+ |
+ map_lambda=power<
+ 'map'
+ trailer<
+ '('
+ arglist<
+ lambdef< 'lambda' fp=NAME ':' xp=any >
+ ','
+ it=any
+ >
+ ')'
+ >
+ >
+ |
+ power<
+ 'map'
+ args=trailer< '(' [any] ')' >
+ >
+ """
+
+ def transform(self, node):
+ results = self.match(node)
+ if "map_lambda" in results:
+ new = ListComp(results.get("xp").clone(),
+ results.get("fp").clone(),
+ results.get("it").clone())
+ else:
+ if "map_none" in results:
+ new = results["arg"].clone()
+ else:
+ if self.in_special_context(node):
+ return None
+ new = node.clone()
+ new.set_prefix("")
+ new = Call(Name("list"), [new])
+ new.set_prefix(node.get_prefix())
+ return new
+
+ P0 = """for_stmt< 'for' any 'in' node=any ':' any* >
+ | list_for< 'for' any 'in' node=any any* >
+ | gen_for< 'for' any 'in' node=any any* >
+ """
+ p0 = patcomp.PatternCompiler().compile_pattern(P0)
+
+ P1 = """
+ power<
+ NAME< 'iter' | 'list' | 'tuple' | 'sorted' >
+ trailer< '(' node=any ')' >
+ any*
+ >
+ """
+ p1 = patcomp.PatternCompiler().compile_pattern(P1)
+
+ P2 = """
+ power<
+ 'sorted'
+ trailer< '(' arglist<node=any any*> ')' >
+ any*
+ >
+ """
+ p2 = patcomp.PatternCompiler().compile_pattern(P2)
+
+ def in_special_context(self, node):
+ p = node.parent
+ if p is None:
+ return False
+ results = {}
+ if self.p0.match(p, results) and results["node"] is node:
+ return True
+
+ pp = p.parent
+ if pp is None:
+ return False
+ results = {}
+ if self.p1.match(pp, results) and results["node"] is node:
+ return True
+
+ ppp = pp.parent
+ if ppp is None:
+ return False
+ results = {}
+ if self.p2.match(ppp, results) and results["node"] is node:
+ return True
+
+ return False
Modified: sandbox/trunk/2to3/fixes/util.py
==============================================================================
--- sandbox/trunk/2to3/fixes/util.py (original)
+++ sandbox/trunk/2to3/fixes/util.py Mon Jul 2 15:20:43 2007
@@ -76,6 +76,30 @@
"""A string leaf"""
return Leaf(token.STRING, string, prefix=prefix)
+def ListComp(xp, fp, it, test=None):
+ """A list comprehension of the form [xp for fp in it if test].
+
+ If test is None, the "if test" part is omitted.
+ """
+ xp.set_prefix("")
+ fp.set_prefix(" ")
+ it.set_prefix(" ")
+ for_leaf = Leaf(token.NAME, "for")
+ for_leaf.set_prefix(" ")
+ in_leaf = Leaf(token.NAME, "in")
+ in_leaf.set_prefix(" ")
+ inner_args = [for_leaf, fp, in_leaf, it]
+ if test:
+ test.set_prefix(" ")
+ if_leaf = Leaf(token.NAME, "if")
+ if_leaf.set_prefix(" ")
+ inner_args.append(Node(syms.list_if, [if_leaf, test]))
+ inner = Node(syms.listmaker, [xp, Node(syms.list_for, inner_args)])
+ return Node(syms.atom,
+ [Leaf(token.LBRACE, "["),
+ inner,
+ Leaf(token.RBRACE, "]")])
+
###########################################################
### Determine whether a node represents a given literal
###########################################################
Modified: sandbox/trunk/2to3/tests/test_fixers.py
==============================================================================
--- sandbox/trunk/2to3/tests/test_fixers.py (original)
+++ sandbox/trunk/2to3/tests/test_fixers.py Mon Jul 2 15:20:43 2007
@@ -1858,6 +1858,100 @@
a = """callable(x, kw=y)"""
self.check(a, a)
+class Test_filter(FixerTestCase):
+ fixer = "filter"
+
+ def test_filter_basic(self):
+ b = """x = filter(None, 'abc')"""
+ a = """x = list(filter(None, 'abc'))"""
+ self.check(b, a)
+
+ b = """x = filter(f, 'abc')"""
+ a = """x = list(filter(f, 'abc'))"""
+ self.check(b, a)
+
+ b = """x = filter(lambda x: x%2 == 0, range(10))"""
+ a = """x = [x for x in range(10) if x%2 == 0]"""
+ self.check(b, a)
+
+ # XXX This (rare) case is not supported
+## b = """x = filter(f, 'abc')[0]"""
+## a = """x = list(filter(f, 'abc'))[0]"""
+## self.check(b, a)
+
+ def test_filter_nochange(self):
+ a = """iter(filter(f, 'abc'))"""
+ self.check(a, a)
+ a = """list(filter(f, 'abc'))"""
+ self.check(a, a)
+ a = """list(filter(f, 'abc'))[0]"""
+ self.check(a, a)
+ a = """tuple(filter(f, 'abc'))"""
+ self.check(a, a)
+ a = """sorted(filter(f, 'abc'))"""
+ self.check(a, a)
+ a = """sorted(filter(f, 'abc'), key=blah)"""
+ self.check(a, a)
+ a = """sorted(filter(f, 'abc'), key=blah)[0]"""
+ self.check(a, a)
+ a = """for i in filter(f, 'abc'): pass"""
+ self.check(a, a)
+ a = """[x for x in filter(f, 'abc')]"""
+ self.check(a, a)
+ a = """(x for x in filter(f, 'abc'))"""
+ self.check(a, a)
+
+class Test_map(FixerTestCase):
+ fixer = "map"
+
+ def test_map_basic(self):
+ b = """x = map(f, 'abc')"""
+ a = """x = list(map(f, 'abc'))"""
+ self.check(b, a)
+
+ b = """x = map(f, 'abc', 'def')"""
+ a = """x = list(map(f, 'abc', 'def'))"""
+ self.check(b, a)
+
+ b = """x = map(None, 'abc')"""
+ a = """x = list('abc')"""
+ self.check(b, a)
+
+ b = """x = map(None, 'abc', 'def')"""
+ a = """x = list(map(None, 'abc', 'def'))"""
+ self.check(b, a)
+
+ b = """x = map(lambda x: x+1, range(4))"""
+ a = """x = [x+1 for x in range(4)]"""
+ self.check(b, a)
+
+ # XXX This (rare) case is not supported
+## b = """x = map(f, 'abc')[0]"""
+## a = """x = list(map(f, 'abc'))[0]"""
+## self.check(b, a)
+
+ def test_map_nochange(self):
+ a = """iter(map(f, 'abc'))"""
+ self.check(a, a)
+ a = """list(map(f, 'abc'))"""
+ self.check(a, a)
+ a = """list(map(f, 'abc'))[0]"""
+ self.check(a, a)
+ a = """tuple(map(f, 'abc'))"""
+ self.check(a, a)
+ a = """sorted(map(f, 'abc'))"""
+ self.check(a, a)
+ a = """sorted(map(f, 'abc'), key=blah)"""
+ self.check(a, a)
+ a = """sorted(map(f, 'abc'), key=blah)[0]"""
+ self.check(a, a)
+ a = """for i in map(f, 'abc'): pass"""
+ self.check(a, a)
+ a = """[x for x in map(f, 'abc')]"""
+ self.check(a, a)
+ a = """(x for x in map(f, 'abc'))"""
+ self.check(a, a)
+
if __name__ == "__main__":
import __main__
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