[PyChecker-checkins] pychecker/pychecker CodeChecks.py, 1.227, 1.228 Stack.py, 1.27, 1.28

[Thomas V. S. <tho...@us...>]

Update of /cvsroot/pychecker/pychecker/pychecker
In directory sfp-cvsdas-2.v30.ch3.sourceforge.com:/tmp/cvs-serv23632/pychecker

Modified Files:
	CodeChecks.py Stack.py 
Log Message:
	* HACKING:
	  Add debian note.
	* pychecker/CodeChecks.py:
	  Add a FIXME for an internal warning.
	* pychecker/Stack.py:
	  Comment, document, and assert assumptions related to
	  attributes and indirections.



Index: CodeChecks.py
===================================================================
RCS file: /cvsroot/pychecker/pychecker/pychecker/CodeChecks.py,v
retrieving revision 1.227
retrieving revision 1.228
diff -u -d -r1.227 -r1.228
--- CodeChecks.py	25 Jan 2011 08:44:45 -0000	1.227
+++ CodeChecks.py	25 Jan 2011 10:32:24 -0000	1.228
@@ -1561,6 +1561,7 @@
 
 def _LOAD_ATTR(oparg, operand, codeSource, code) :
     # FIXME: how can LOAD_ATTR happen without a stack ?
+    # FIXME: add an internal warning here
     if len(code.stack) > 0 :
         top = code.stack[-1]
         _checkAttribute(top, operand, codeSource, code)

Index: Stack.py
===================================================================
RCS file: /cvsroot/pychecker/pychecker/pychecker/Stack.py,v
retrieving revision 1.27
retrieving revision 1.28
diff -u -d -r1.27 -r1.28
--- Stack.py	9 Jan 2011 17:19:43 -0000	1.27
+++ Stack.py	25 Jan 2011 10:32:24 -0000	1.28
@@ -21,6 +21,8 @@
 TYPE_GLOBAL = "-global-"
 TYPE_EXCEPT = "-except-"
 
+# conventions for Items:
+# a method call has data ('self', methodName), type ATTRIBUTE
 class Item:
     """
     Representation of data on the stack
@@ -72,8 +74,31 @@
         return self.data is None and self.const
 
     def isMethodCall(self, c, methodArgName):
-        return self.type == TYPE_ATTRIBUTE and c != None and \
-               len(self.data) == 2 and self.data[0] == methodArgName
+        """
+        @param methodArgName: the first argument 
+        Check if the stack item is a method call.
+
+        @type  methodArgName: str
+        @param methodArgName: the name of the first argument for method calls;
+                              usually self.
+        """
+        if self.type != TYPE_ATTRIBUTE:
+            return False
+
+        # FIXME: we only check if c is not None; that doesn't mean it
+        # has the given methodArgName
+        if c is None:
+            return False
+
+        if len(self.data) != 2:
+            # no object indirection happening
+            return False
+
+        if self.data[0] != methodArgName:
+            # indirection does not start with first argument for method calls
+            return False
+
+        return True
 
     def isLocals(self):
         return self.type == types.DictType and self.data == LOCALS
@@ -111,6 +136,8 @@
         return TYPE_UNKNOWN
 
     def getName(self):
+        # if the item is an attribute but not a string, it's a tuple
+        # of object indirections
         if self.type == TYPE_ATTRIBUTE and type(self.data) != types.StringType:
             strValue = ""
             # convert the tuple into a string ('self', 'data') -> self.data
@@ -120,10 +147,27 @@
         return utils.safestr(self.data)
 
     def addAttribute(self, attr):
-        if type(self.data) == types.TupleType:
-            self.data = self.data + (attr,)
-        else:
-            self.data = (self.data, attr)
+        """
+        Replaces self with a stack item representing the dereferencing of
+        its attribute.
+
+        For example, if the stack item describes a class, calling this method
+        will replace the stack item with one describing the attribute of
+        this class.
+
+        @type  attr: str
+        """
+        # only called through LOAD_ATTR, which replaces TOS with the
+        # dereferencing result
+        assert type(attr) is str
+
+        # make sure that adding an attribute makes data a tuple if it
+        # wasn't yet
+        if type(self.data) != types.TupleType:
+            self.data = (self.data, )
+
+        self.data = self.data + (attr,)
+
         self.type = TYPE_ATTRIBUTE