pylint fixes

--HG--
branch : _ast_compat

1 files changed, 49 insertions, 1 deletions

diff --git a/infutils.py b/infutils.py
index 365df00c..27d67061 100644
--- a/infutils.py
+++ b/infutils.py
@@ -25,7 +25,8 @@ __doctype__ = "restructuredtext en"
 from logilab.common.compat import chain, imap
 
 from logilab.astng._exceptions import InferenceError, NotFoundError, UnresolvableName
-from logilab.astng.nodes import Proxy_, List, Tuple, Function
+from logilab.astng.nodes import Proxy_, List, Tuple, Function, If, TryExcept
+
 
 class Proxy(Proxy_):
     """a simple proxy object"""
@@ -76,6 +77,53 @@ class InferenceContext(object):
         return clone
 
 
+def are_exclusive(stmt1, stmt2):
+    """return true if the two given statements are mutually exclusive
+
+    algorithm :
+     1) index stmt1's parents
+     2) climb among stmt2's parents until we find a common parent
+     3) if the common parent is a If or TryExcept statement, look if nodes are
+        in exclusive branchs
+    """
+    # index stmt1's parents
+    stmt1_parents = {}
+    children = {}
+    node = stmt1.parent
+    previous = stmt1
+    while node:
+        stmt1_parents[node] = 1
+        children[node] = previous
+        previous = node
+        node = node.parent
+    # climb among stmt2's parents until we find a common parent
+    node = stmt2.parent
+    previous = stmt2
+    while node:
+        if stmt1_parents.has_key(node):
+            # if the common parent is a If or TryExcept statement, look if
+            # nodes are in exclusive branchs
+            if isinstance(node, If):
+                if (node.locate_child(previous)[1]
+                    is not node.locate_child(children[node])[1]):
+                    return True
+            elif isinstance(node, TryExcept):
+                c2attr, c2node = node.locate_child(previous)
+                c1attr, c1node = node.locate_child(children[node])
+                if c1node is not c2node:
+                    if ((c2attr == 'body' and c1attr == 'handlers') or
+                        (c2attr == 'handlers' and c1attr == 'body') or
+                        (c2attr == 'handlers' and c1attr == 'orelse') or
+                        (c2attr == 'orelse' and c1attr == 'handlers')):
+                        return True
+                elif c2attr == 'handlers' and c1attr == 'handlers':
+                    return previous is not children[node]
+            return False
+        previous = node
+        node = node.parent
+    return False
+
+
 def unpack_infer(stmt, context=None):
     """return an iterator on nodes infered by the given statement if the infered
     value is a list or a tuple, recurse on it to get values infered by its