Don't emit 'attribute-defined-outside-init' if the attribute was set by a function call in a defining method. Closes issue #192.

3 files changed, 69 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index b4df421..26f417e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -30,6 +30,9 @@ ChangeLog for Pylint
 
     * Properly handle nested format string fields. Closes issue #294.
 
+    * Don't emit 'attribute-defined-outside-init' if the attribute
+      was set by a function call in a defining method. Closes issue #192.
+
 2014-07-26  --  1.3.0
 
     * Allow hanging continued indentation for implicitly concatenated
diff --git a/checkers/classes.py b/checkers/classes.py
index 61769f2..b0d827a 100644
--- a/checkers/classes.py
+++ b/checkers/classes.py
@@ -35,6 +35,33 @@ else:
     NEXT_METHOD = 'next'
 ITER_METHODS = ('__iter__', '__getitem__')
 
+def _called_by_methods(func, klass, defining_methods):
+    """ Check if the func was called by any method from
+    *defining_methods*, belonging to the *klass*.
+    Returns True if so, False otherwise.
+    """
+    if not isinstance(func, astroid.Function):
+        return False
+    for meth in defining_methods:
+        try:
+            methods = klass.getattr(meth)
+        except astroid.NotFoundError:
+            continue
+        for method in methods:
+            for callfunc in method.nodes_of_class(astroid.CallFunc):
+                try:
+                    bound = next(callfunc.func.infer())
+                except (astroid.InferenceError, StopIteration):
+                    continue
+                if not isinstance(bound, astroid.BoundMethod):
+                    continue
+                func_obj = bound._proxied
+                if isinstance(func_obj, astroid.UnboundMethod):
+                    func_obj = func_obj._proxied
+                if func_obj.name == func.name:
+                    return True
+    return False
+
 def class_is_abstract(node):
     """return true if the given class node should be considered as an abstract
     class
@@ -301,6 +328,12 @@ a metaclass class method.'}
                 except astroid.NotFoundError:
                     for node in nodes:
                         if node.frame().name not in defining_methods:
+                            # If the attribute was set by a callfunc in any
+                            # of the defining methods, then don't emit
+                            # the warning.
+                            if _called_by_methods(node.frame(), cnode,
+                                                  defining_methods):
+                                continue
                             self.add_message('attribute-defined-outside-init',
                                              args=attr, node=node)
 
diff --git a/test/input/func_defining-attr-methods_order.py b/test/input/func_defining-attr-methods_order.py
index 888b192..28918f2 100644
--- a/test/input/func_defining-attr-methods_order.py
+++ b/test/input/func_defining-attr-methods_order.py
@@ -1,4 +1,4 @@
-# pylint: disable=C0103
+# pylint: disable=C0103, too-few-public-methods
 
 ''' Test that y is defined properly, z is not.
     Default defining methods are __init__,
@@ -39,3 +39,35 @@ class B(A):
     def test(self):
         """ test """
         self.z = 44
+
+class C(object):
+    ''' class C '''
+
+    def __init__(self):
+        self._init()
+
+    def _init(self):
+        ''' called by __init__ '''
+        self.z = 44
+
+class D(object):
+    ''' class D '''
+
+    def setUp(self):
+        ''' defining method '''
+        self.set_z()
+
+    def set_z(self):
+        ''' called by the parent. '''
+        self.z = 42
+
+class E(object):
+    ''' Reassign the function. '''
+
+    def __init__(self):
+        i = self._init
+        i()
+
+    def _init(self):
+        ''' called by __init__ '''
+        self.z = 44