[Python-checkins] r58055 - in sandbox/trunk/2to3: fixes/fix_tuple_params.py tests/test_fixers.py

Sat Sep 8 23:02:43 CEST 2007

Author: collin.winter
Date: Sat Sep 8 23:02:43 2007
New Revision: 58055
Modified:
 sandbox/trunk/2to3/fixes/fix_tuple_params.py
 sandbox/trunk/2to3/tests/test_fixers.py
Log:
Make fix_tuple_params handle unnecessary parens around lambda parameters; this fixes issue #1107.
Modified: sandbox/trunk/2to3/fixes/fix_tuple_params.py
==============================================================================

--- sandbox/trunk/2to3/fixes/fix_tuple_params.py	(original)
+++ sandbox/trunk/2to3/fixes/fix_tuple_params.py	Sat Sep 8 23:02:43 2007
@@ -12,6 +12,9 @@
 It will also support lambdas:
 
 lambda (x, y): x + y -> lambda t: t[0] + t[1]
+
+ # The parens are a syntax error in Python 3
+ lambda (x): x + y -> lambda x: x + y
 """
 # Author: Collin Winter
 
@@ -30,7 +33,11 @@
 funcdef< 'def' any parameters< '(' args=any ')' >
 ['->' any] ':' suite=any+ >
 |
- lambda=lambdef< 'lambda' args=vfpdef< '(' vfplist< any+ > ')' > ':' body=any >"""
+ lambda=
+ lambdef< 'lambda' args=vfpdef< '(' inner=any ')' >
+ ':' body=any
+ >
+ """
 
 def transform(self, node, results):
 if "lambda" in results:
@@ -97,6 +104,14 @@
 def transform_lambda(self, node, results):
 args = results["args"]
 body = results["body"]
+ inner = simplify_args(results["inner"])
+
+ # Replace lambda ((((x)))): x with lambda x: x
+ if inner.type == token.NAME:
+ inner = inner.clone()
+ inner.set_prefix(args.get_prefix())
+ args.replace(inner)
+ return
 
 params = find_params(args)
 to_index = map_to_index(params)
@@ -116,6 +131,17 @@
 
 ### Helper functions for transform_lambda()
 
+def simplify_args(node):
+ if node.type in (syms.vfplist, token.NAME):
+ return node
+ elif node.type == syms.vfpdef:
+ # These look like vfpdef< '(' x ')' > where x is NAME
+ # or another vfpdef instance (leading to recursion).
+ while node.type == syms.vfpdef:
+ node = node.children[1]
+ return node
+ raise RuntimeError("Received unexpected node %s" % node)
+
 def find_params(node):
 if node.type == syms.vfpdef:
 return find_params(node.children[1])
Modified: sandbox/trunk/2to3/tests/test_fixers.py
==============================================================================
--- sandbox/trunk/2to3/tests/test_fixers.py	(original)
+++ sandbox/trunk/2to3/tests/test_fixers.py	Sat Sep 8 23:02:43 2007
@@ -1531,20 +1531,33 @@
 s = """lambda x: x + 5"""
 self.unchanged(s)
 
- # Note the parens around x
- s = """lambda (x): x + 5"""
- self.unchanged(s)
+ def test_lambda_parens_single_arg(self):
+ b = """lambda (x): x + 5"""
+ a = """lambda x: x + 5"""
+ self.check(b, a)
+
+ b = """lambda ((((x)))): x + 5"""
+ a = """lambda x: x + 5"""
+ self.check(b, a)
 
 def test_lambda_simple(self):
 b = """lambda (x, y): x + f(y)"""
 a = """lambda x_y: x_y[0] + f(x_y[1])"""
 self.check(b, a)
 
+ b = """lambda (((x, y))): x + f(y)"""
+ a = """lambda x_y: x_y[0] + f(x_y[1])"""
+ self.check(b, a)
+
 def test_lambda_one_tuple(self):
 b = """lambda (x,): x + f(x)"""
 a = """lambda x1: x1[0] + f(x1[0])"""
 self.check(b, a)
 
+ b = """lambda (((x,))): x + f(x)"""
+ a = """lambda x1: x1[0] + f(x1[0])"""
+ self.check(b, a)
+
 def test_lambda_simple_multi_use(self):
 b = """lambda (x, y): x + x + f(x) + x"""
 a = """lambda x_y: x_y[0] + x_y[0] + f(x_y[0]) + x_y[0]"""
@@ -1560,6 +1573,10 @@
 a = """lambda x_y_z: x_y_z[0] + x_y_z[1][0] + x_y_z[1][1]"""
 self.check(b, a)
 
+ b = """lambda (((x, (y, z)))): x + y + z"""
+ a = """lambda x_y_z: x_y_z[0] + x_y_z[1][0] + x_y_z[1][1]"""
+ self.check(b, a)
+
 def test_lambda_nested_multi_use(self):
 b = """lambda (x, (y, z)): x + y + f(y)"""
 a = """lambda x_y_z: x_y_z[0] + x_y_z[1][0] + f(x_y_z[1][0])"""
