Start support for git aliases

tests/test_main.py

@@ -84,7 +84,7 @@ class TestGetCommand(object):
                                       shell=True,
                                       stdout=PIPE,
                                       stderr=PIPE,
-                                      env={'LANG': 'C'})
+                                      env={'LANG': 'C', 'GIT_TRACE': 1})
 
     @pytest.mark.parametrize('args, result', [
         (['thefuck', 'ls', '-la'], 'ls -la'),

tests/test_utils.py

@@ -1,6 +1,6 @@
 import pytest
 from mock import Mock
-from thefuck.utils import sudo_support, wrap_settings, memoize, get_closest
+from thefuck.utils import git_support, sudo_support, wrap_settings, memoize, get_closest
 from thefuck.types import Settings
 from tests.utils import Command
 
@@ -26,6 +26,15 @@ def test_sudo_support(return_value, command, called, result):
     fn.assert_called_once_with(Command(called), None)
 
 
+@pytest.mark.parametrize('called, command, stderr', [
+    ('git co', "git 'checkout'", "19:22:36.299340 git.c:282   trace: alias expansion: co => 'checkout'"),
+    ('git com file', "git 'commit' '--verbose' file", "19:23:25.470911 git.c:282   trace: alias expansion: com => 'commit' '--verbose'")])
+def test_git_support(called, command, stderr):
+    @git_support
+    def fn(command, settings): return command.script
+    assert fn(Command(script=called, stderr=stderr), None) == command
+
+
 def test_memoize():
     fn = Mock(__name__='fn')
     memoized = memoize(fn)

thefuck/main.py

@@ -82,7 +82,7 @@ def get_command(settings, args):
     script = shells.from_shell(script)
     logs.debug('Call: {}'.format(script), settings)
     result = Popen(script, shell=True, stdout=PIPE, stderr=PIPE,
-                   env=dict(os.environ, LANG='C'))
+                   env=dict(os.environ, LANG='C', GIT_TRACE=1))
     if wait_output(settings, result):
         return types.Command(script, result.stdout.read().decode('utf-8'),
                              result.stderr.read().decode('utf-8'))

thefuck/utils.py

@@ -2,6 +2,7 @@ from difflib import get_close_matches
 from functools import wraps
 import os
 import pickle
+import re
 import six
 from .types import Command
 
@@ -73,6 +74,25 @@ def sudo_support(fn):
     return wrapper
 
 
+def git_support(fn):
+    """Resolve git aliases."""
+    @wraps(fn)
+    def wrapper(command, settings):
+        if (command.script.startswith('git') and
+                'trace: alias expansion:' in command.stderr):
+
+            search = re.search("trace: alias expansion: ([^ ]*) => ([^\n]*)",
+                               command.stderr)
+            alias = search.group(1)
+            expansion = search.group(2)
+            new_script = command.script.replace(alias, expansion)
+
+            command = Command._replace(command, script=new_script)
+        return fn(command, settings)
+
+    return wrapper
+
+
 def memoize(fn):
     """Caches previous calls to the function."""
     memo = {}