Fix an 'unused-import' false positive, when the error was emitted for all the members imported with 'from import' form. Closes issue #304.

4 files changed, 19 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index 2f082cf72..b39c9d612 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -40,6 +40,10 @@ ChangeLog for Pylint
 
     * Don't emit 'import-error' if an import was protected by a try-except,
       which excepted ImportError.
+ 
+    * Fix an 'unused-import' false positive, when the error was emitted
+      for all the members imported with 'from import' form.
+      Closes issue #304.
 
 2014-07-26  --  1.3.0
 
diff --git a/checkers/variables.py b/checkers/variables.py
index 19e526bc4..747195b5f 100644
--- a/checkers/variables.py
+++ b/checkers/variables.py
@@ -333,14 +333,19 @@ builtins. Remember that you should avoid to define new builtins when possible.'
                 if not isinstance(stmt, (astroid.From, astroid.Import)):
                     continue
                 for imports in stmt.names:
+                    name2 = None
                     if imports[0] == "*":
                         # In case of wildcard import,
                         # pick the name from inside of imported module.
                         name2 = name
                     else:
-                        # pick explicitly imported name
-                        name2 = imports[0]
-                    if name2 not in local_names:
+                        if imports[0].find(".") > -1 or name in imports:
+                            # Most likely something like 'xml.etree',
+                            # which will appear in the .locals as
+                            # 'xml'.
+                            # Only pick the name if it wasn't consumed.
+                            name2 = imports[0]
+                    if name2 and name2 not in local_names:
                         local_names[name2] = stmt
         local_names = sorted(local_names.iteritems(),
                              key=lambda a: a[1].fromlineno)
@@ -355,10 +360,13 @@ builtins. Remember that you should avoid to define new builtins when possible.'
                 as_name = imports[1]
                 if real_name in checked:
                     continue
+                if name not in (real_name, as_name):
+                    continue
                 checked.add(real_name)
 
-                if isinstance(stmt, astroid.Import) or (isinstance(stmt, astroid.From) \
-                                                        and not stmt.modname):
+                if (isinstance(stmt, astroid.Import) or
+                        (isinstance(stmt, astroid.From) and
+                         not stmt.modname)):
                     if as_name is None:
                         msg = "import %s" % imported_name
                     else:
diff --git a/test/functional/unused_import.py b/test/functional/unused_import.py
index c4e51867b..458798c1b 100644
--- a/test/functional/unused_import.py
+++ b/test/functional/unused_import.py
@@ -4,5 +4,6 @@ import xml.sax  # [unused-import]
 import os.path as test  # [unused-import]
 from sys import argv as test2  # [unused-import]
 from sys import flags  # [unused-import]
-# +1:[unused-import,unused-import,unused-import]
+# +1:[unused-import,unused-import]
 from collections import deque, OrderedDict, Counter
+DATA = Counter()
diff --git a/test/functional/unused_import.txt b/test/functional/unused_import.txt
index 768082c01..e50c2990d 100644
--- a/test/functional/unused_import.txt
+++ b/test/functional/unused_import.txt
@@ -3,6 +3,5 @@ unused-import:3::Unused import xml.sax
 unused-import:4::Unused os.path imported as test
 unused-import:5::Unused argv imported from sys as test2
 unused-import:6::Unused flags imported from sys
-unused-import:8::Unused Counter imported from collections
 unused-import:8::Unused OrderedDict imported from collections
 unused-import:8::Unused deque imported from collections