PEP-0318, @decorator-style. In Guido's words:

"@ seems the syntax that everybody can hate equally"
Implementation by Mark Russell, from SF #979728.

6 files changed, 284 insertions, 15 deletions

diff --git a/Lib/test/output/test_tokenize b/Lib/test/output/test_tokenize
index ea55181..b78a223 100644
--- a/Lib/test/output/test_tokenize
+++ b/Lib/test/output/test_tokenize
@@ -645,4 +645,15 @@ test_tokenize
 174,29-174,30:	OP	')'
 174,30-174,31:	NEWLINE	'\n'
 175,0-175,1:	NL	'\n'
-176,0-176,0:	ENDMARKER	''
+176,0-176,1:	OP	'@'
+176,1-176,13:	NAME	'staticmethod'
+176,13-176,14:	NEWLINE	'\n'
+177,0-177,3:	NAME	'def'
+177,4-177,7:	NAME	'foo'
+177,7-177,8:	OP	'('
+177,8-177,9:	OP	')'
+177,9-177,10:	OP	':'
+177,11-177,15:	NAME	'pass'
+177,15-177,16:	NEWLINE	'\n'
+178,0-178,1:	NL	'\n'
+179,0-179,0:	ENDMARKER	''
diff --git a/Lib/test/pyclbr_input.py b/Lib/test/pyclbr_input.py
new file mode 100644
index 0000000..b410fcc
--- /dev/null
+++ b/Lib/test/pyclbr_input.py
@@ -0,0 +1,33 @@
+"""Test cases for test_pyclbr.py"""
+
+def f(): pass
+
+class Other(object):
+    @classmethod
+    def foo(c): pass
+
+    def om(self): pass
+
+class B (object):
+    def bm(self): pass
+    
+class C (B):
+    foo = Other().foo
+    om = Other.om
+    
+    d = 10
+
+    # XXX: This causes test_pyclbr.py to fail, but only because the
+    #      introspection-based is_method() code in the test can't
+    #      distinguish between this and a geniune method function like m().
+    #      The pyclbr.py module gets this right as it parses the text.
+    #
+    #f = f
+    
+    def m(self): pass
+    
+    @staticmethod
+    def sm(self): pass
+
+    @classmethod
+    def cm(self): pass
diff --git a/Lib/test/test_decorators.py b/Lib/test/test_decorators.py
new file mode 100644
index 0000000..98d5d3e
--- /dev/null
+++ b/Lib/test/test_decorators.py
@@ -0,0 +1,194 @@
+import unittest
+from test import test_support
+
+def funcattrs(**kwds):
+    def decorate(func):
+        func.__dict__.update(kwds)
+        return func
+    return decorate
+
+class MiscDecorators (object):
+    @staticmethod
+    def author(name):
+        def decorate(func):
+            func.__dict__['author'] = name
+            return func
+        return decorate
+
+# -----------------------------------------------
+
+class DbcheckError (Exception):
+    def __init__(self, exprstr, func, args, kwds):
+        # A real version of this would set attributes here
+        Exception.__init__(self, "dbcheck %r failed (func=%s args=%s kwds=%s)" %
+                           (exprstr, func, args, kwds))
+    
+    
+def dbcheck(exprstr, globals=None, locals=None):
+    "Decorator to implement debugging assertions"
+    def decorate(func):
+        expr = compile(exprstr, "dbcheck-%s" % func.func_name, "eval")
+        def check(*args, **kwds):
+            if not eval(expr, globals, locals):
+                raise DbcheckError(exprstr, func, args, kwds)
+            return func(*args, **kwds)
+        return check
+    return decorate
+
+# -----------------------------------------------
+
+def countcalls(counts):
+    "Decorator to count calls to a function"
+    def decorate(func):
+        name = func.func_name
+        counts[name] = 0
+        def call(*args, **kwds):
+            counts[name] += 1
+            return func(*args, **kwds)
+        # XXX: Would like to say: call.func_name = func.func_name here
+        #      to make nested decorators work in any order, but func_name
+        #      is a readonly attribute
+        return call
+    return decorate
+
+# -----------------------------------------------
+
+def memoize(func):
+    saved = {}
+    def call(*args):
+        try:
+            return saved[args]
+        except KeyError:
+            res = func(*args)
+            saved[args] = res
+            return res
+        except TypeError:
+            # Unhashable argument
+            return func(*args)
+    return call
+            
+# -----------------------------------------------
+
+class TestDecorators(unittest.TestCase):
+
+    def test_single(self):
+        class C(object):
+            @staticmethod
+            def foo(): return 42
+        self.assertEqual(C.foo(), 42)
+        self.assertEqual(C().foo(), 42)
+
+    def test_dotted(self):
+        decorators = MiscDecorators()
+        @decorators.author('Cleese')
+        def foo(): return 42
+        self.assertEqual(foo(), 42)
+        self.assertEqual(foo.author, 'Cleese')
+
+    def test_argforms(self):
+        # A few tests of argument passing, as we use restricted form
+        # of expressions for decorators.
+        
+        def noteargs(*args, **kwds):
+            def decorate(func):
+                setattr(func, 'dbval', (args, kwds))
+                return func
+            return decorate
+
+        args = ( 'Now', 'is', 'the', 'time' )
+        kwds = dict(one=1, two=2)
+        @noteargs(*args, **kwds)
+        def f1(): return 42
+        self.assertEqual(f1(), 42)
+        self.assertEqual(f1.dbval, (args, kwds))
+
+        @noteargs('terry', 'gilliam', eric='idle', john='cleese')
+        def f2(): return 84
+        self.assertEqual(f2(), 84)
+        self.assertEqual(f2.dbval, (('terry', 'gilliam'),
+                                     dict(eric='idle', john='cleese')))
+
+        @noteargs(1, 2,)
+        def f3(): pass
+        self.assertEqual(f3.dbval, ((1, 2), {}))
+
+    def test_dbcheck(self):
+        @dbcheck('args[1] is not None')
+        def f(a, b):
+            return a + b
+        self.assertEqual(f(1, 2), 3)
+        self.assertRaises(DbcheckError, f, 1, None)
+
+    def test_memoize(self):
+        # XXX: This doesn't work unless memoize is the last decorator -
+        #      see the comment in countcalls.
+        counts = {}
+        @countcalls(counts) @memoize 
+        def double(x):
+            return x * 2
+
+        self.assertEqual(counts, dict(double=0))
+
+        # Only the first call with a given argument bumps the call count:
+        #
+        self.assertEqual(double(2), 4)
+        self.assertEqual(counts['double'], 1)
+        self.assertEqual(double(2), 4)
+        self.assertEqual(counts['double'], 1)
+        self.assertEqual(double(3), 6)
+        self.assertEqual(counts['double'], 2)
+
+        # Unhashable arguments do not get memoized:
+        #
+        self.assertEqual(double([10]), [10, 10])
+        self.assertEqual(counts['double'], 3)
+        self.assertEqual(double([10]), [10, 10])
+        self.assertEqual(counts['double'], 4)
+
+    def test_errors(self):
+        # Test syntax restrictions - these are all compile-time errors:
+        #
+        for expr in [ "1+2", "x[3]", "(1, 2)" ]:
+            # Sanity check: is expr is a valid expression by itself?
+            compile(expr, "testexpr", "exec")
+            
+            codestr = "@%s\ndef f(): pass" % expr
+            self.assertRaises(SyntaxError, compile, codestr, "test", "exec")
+
+        # Test runtime errors
+
+        def unimp(func):
+            raise NotImplementedError
+        context = dict(nullval=None, unimp=unimp)
+        
+        for expr, exc in [ ("undef", NameError),
+                           ("nullval", TypeError),
+                           ("nullval.attr", AttributeError),
+                           ("unimp", NotImplementedError)]:
+            codestr = "@%s\ndef f(): pass\nassert f() is None" % expr
+            code = compile(codestr, "test", "exec")
+            self.assertRaises(exc, eval, code, context)
+
+    def test_double(self):
+        class C(object):
+            @funcattrs(abc=1, xyz="haha")
+            @funcattrs(booh=42)
+            def foo(self): return 42
+        self.assertEqual(C().foo(), 42)
+        self.assertEqual(C.foo.abc, 1)
+        self.assertEqual(C.foo.xyz, "haha")
+        self.assertEqual(C.foo.booh, 42)
+
+    def test_order(self):
+        class C(object):
+            @funcattrs(abc=1) @staticmethod
+            def foo(): return 42
+        # This wouldn't work if staticmethod was called first
+        self.assertEqual(C.foo(), 42)
+        self.assertEqual(C().foo(), 42)
+
+def test_main():
+    test_support.run_unittest(TestDecorators)
+
+if __name__=="__main__":
+    test_main()
diff --git a/Lib/test/test_parser.py b/Lib/test/test_parser.py
index 9652f6b..978ce57 100644
--- a/Lib/test/test_parser.py
+++ b/Lib/test/test_parser.py
@@ -15,8 +15,8 @@ class RoundtripLegalSyntaxTestCase(unittest.TestCase):
         t = st1.totuple()
         try:
             st2 = parser.sequence2st(t)
-        except parser.ParserError:
-            self.fail("could not roundtrip %r" % s)
+        except parser.ParserError, why:
+            self.fail("could not roundtrip %r: %s" % (s, why))
 
         self.assertEquals(t, st2.totuple(),
                           "could not re-generate syntax tree")
@@ -119,6 +119,14 @@ class RoundtripLegalSyntaxTestCase(unittest.TestCase):
         self.check_suite("def f(a, b, foo=bar, *args, **kw): pass")
         self.check_suite("def f(a, b, foo=bar, **kw): pass")
 
+        self.check_suite("@staticmethod\n"
+                         "def f(): pass")
+        self.check_suite("@staticmethod\n"
+                         "@funcattrs(x, y)\n"
+                         "def f(): pass")
+        self.check_suite("@funcattrs()\n"
+                         "def f(): pass")
+
     def test_import_from_statement(self):
         self.check_suite("from sys.path import *")
         self.check_suite("from sys.path import dirname")
diff --git a/Lib/test/test_pyclbr.py b/Lib/test/test_pyclbr.py
index 48e8bf7..eddd593 100644
--- a/Lib/test/test_pyclbr.py
+++ b/Lib/test/test_pyclbr.py
@@ -8,6 +8,9 @@ from types import ClassType, FunctionType, MethodType
 import pyclbr
 from unittest import TestCase
 
+StaticMethodType = type(staticmethod(lambda: None))
+ClassMethodType = type(classmethod(lambda c: None))
+
 # This next line triggers an error on old versions of pyclbr.
 
 from commands import getstatus
@@ -43,11 +46,10 @@ class PyclbrTest(TestCase):
             print >>sys.stderr, "***",key
         self.failUnless(obj.has_key(key))
 
-    def assertEquals(self, a, b, ignore=None):
+    def assertEqualsOrIgnored(self, a, b, ignore):
         ''' succeed iff a == b or a in ignore or b in ignore '''
-        if (ignore == None) or (a in ignore) or (b in ignore): return
-
-        unittest.TestCase.assertEquals(self, a, b)
+        if a not in ignore and b not in ignore:
+            self.assertEquals(a, b)
 
     def checkModule(self, moduleName, module=None, ignore=()):
         ''' succeed iff pyclbr.readmodule_ex(modulename) corresponds
@@ -62,11 +64,22 @@ class PyclbrTest(TestCase):
 
         dict = pyclbr.readmodule_ex(moduleName)
 
-        def ismethod(obj, name):
-            if not  isinstance(obj, MethodType):
-                return False
-            if obj.im_self is not None:
-                return False
+        def ismethod(oclass, obj, name):
+            classdict = oclass.__dict__
+            if isinstance(obj, FunctionType):
+                if not isinstance(classdict[name], StaticMethodType):
+                    return False
+            else:
+                if not  isinstance(obj, MethodType):
+                    return False
+                if obj.im_self is not None:
+                    if (not isinstance(classdict[name], ClassMethodType) or
+                        obj.im_self is not oclass):
+                        return False
+                else:
+                    if not isinstance(classdict[name], FunctionType):
+                        return False
+
             objname = obj.__name__
             if objname.startswith("__") and not objname.endswith("__"):
                 objname = "_%s%s" % (obj.im_class.__name__, objname)
@@ -81,7 +94,7 @@ class PyclbrTest(TestCase):
             if isinstance(value, pyclbr.Function):
                 self.assertEquals(type(py_item), FunctionType)
             else:
-                self.assertEquals(type(py_item), ClassType)
+                self.failUnless(isinstance(py_item, (ClassType, type)))
                 real_bases = [base.__name__ for base in py_item.__bases__]
                 pyclbr_bases = [ getattr(base, 'name', base)
                                  for base in value.super ]
@@ -94,7 +107,7 @@ class PyclbrTest(TestCase):
 
                 actualMethods = []
                 for m in py_item.__dict__.keys():
-                    if ismethod(getattr(py_item, m), m):
+                    if ismethod(py_item, getattr(py_item, m), m):
                         actualMethods.append(m)
                 foundMethods = []
                 for m in value.methods.keys():
@@ -107,7 +120,8 @@ class PyclbrTest(TestCase):
                     self.assertListEq(foundMethods, actualMethods, ignore)
                     self.assertEquals(py_item.__module__, value.module)
 
-                    self.assertEquals(py_item.__name__, value.name, ignore)
+                    self.assertEqualsOrIgnored(py_item.__name__, value.name,
+                                               ignore)
                     # can't check file or lineno
                 except:
                     print >>sys.stderr, "class=%s" % py_item
@@ -132,6 +146,12 @@ class PyclbrTest(TestCase):
         self.checkModule('rfc822')
         self.checkModule('difflib')
 
+    def test_decorators(self):
+        # XXX: See comment in pyclbr_input.py for a test that would fail
+        #      if it were not commented out.
+        #
+        self.checkModule('test.pyclbr_input')
+        
     def test_others(self):
         cm = self.checkModule
 
diff --git a/Lib/test/tokenize_tests.txt b/Lib/test/tokenize_tests.txt
index e990a36..4ef3bf1 100644
--- a/Lib/test/tokenize_tests.txt
+++ b/Lib/test/tokenize_tests.txt
@@ -173,3 +173,6 @@ x = -1*1/1 + 1*1 - ---1*1
 import sys, time
 x = sys.modules['time'].time()
 
+@staticmethod
+def foo(): pass
+