Emit a warning when .xreadlines() is accessed

3 files changed, 22 insertions, 5 deletions

diff --git a/ChangeLog b/ChangeLog
index c412976e3..758967329 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -8,6 +8,7 @@ What's New in Pylint 1.9.0?
 
 Release date:
 
+    * Added `xreadlines-attribute`, emitted when the `xreadlines()` attribute is accessed.
 
     * The Python 3 porting mode can now run with Python 3 as well.
 
diff --git a/pylint/checkers/python3.py b/pylint/checkers/python3.py
index 3baac4ae2..b9e1e299e 100644
--- a/pylint/checkers/python3.py
+++ b/pylint/checkers/python3.py
@@ -405,6 +405,10 @@ class Python3Checker(checkers.BaseChecker):
                   'deprecated-urllib-function',
                   'Used when accessing a field on urllib module that has been '
                   'removed or moved in Python 3.',),
+        'W1659': ('Accessing a removed xreadlines attribute',
+                  'xreadlines-attribute',
+                  'Used when accessing the xreadlines() function on a file stream, '
+                  'removed in Python 3.',),
     }
 
     _bad_builtins = frozenset([
@@ -823,18 +827,22 @@ class Python3Checker(checkers.BaseChecker):
     def visit_delattr(self, node):
         self.visit_attribute(node)
 
-    @utils.check_messages('exception-message-attribute')
+    @utils.check_messages('exception-message-attribute', 'xreadlines-attribute')
     def visit_attribute(self, node):
-        """Look for accessing message on exceptions. """
-        message = 'message'
+        """Look for removed attributes"""
+        if node.attrname == 'xreadlines':
+            self.add_message('xreadlines-attribute', node=node)
+            return
+
+        exception_message = 'message'
         try:
             for inferred in node.expr.infer():
                 if (isinstance(inferred, astroid.Instance) and
                         utils.inherit_from_std_ex(inferred)):
-                    if node.attrname == message:
+                    if node.attrname == exception_message:
 
                         # Exceptions with .message clearly defined are an exception
-                        if message in inferred.instance_attrs:
+                        if exception_message in inferred.instance_attrs:
                             continue
                         self.add_message('exception-message-attribute', node=node)
                 if isinstance(inferred, astroid.Module):
diff --git a/pylint/test/unittest_checker_python3.py b/pylint/test/unittest_checker_python3.py
index 374500f3e..c5800f493 100644
--- a/pylint/test/unittest_checker_python3.py
+++ b/pylint/test/unittest_checker_python3.py
@@ -494,6 +494,14 @@ class TestPython3Checker(testutils.CheckerTestCase):
         with self.assertAddsMessages(message):
             self.checker.visit_raise(node)
 
+    def test_xreadlines_attribute(self):
+        node = astroid.extract_node("""
+        f.xreadlines #@
+        """)
+        message = testutils.Message('xreadlines-attribute', node=node)
+        with self.assertAddsMessages(message):
+            self.checker.visit_attribute(node)
+
     def test_exception_message_attribute(self):
         node = astroid.extract_node("""
         try: