Simplify the initialization of Git objects in Host.

third_party/WebKit/Tools/Scripts/webkitpy/common/host.py

 # Copyright (c) 2010 Google Inc. All rights reserved.
 # Copyright (c) 2009 Apple Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 10 matching lines @@
 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 import logging
-import sys
 
 from webkitpy.common.checkout.scm.git import Git
 from webkitpy.common.config.builders import BUILDERS
+from webkitpy.common.net import web
 from webkitpy.common.net.buildbot import BuildBot
-from webkitpy.common.net import web
 from webkitpy.common.system.system_host import SystemHost
 from webkitpy.layout_tests.builder_list import BuilderList
 from webkitpy.layout_tests.port.factory import PortFactory
 
 
 _log = logging.getLogger(__name__)
 
 
 class Host(SystemHost):
 
@@ skipping 23 matching lines @@
         # the locale environment variables inside webkitpy.
         # If we don't do this, programs like SVN will output localized
         # messages and svn.py will fail to parse them.
         # FIXME: We should do these overrides *only* for the subprocesses we know need them!
         # This hack only works in unix environments.
         self.environ['LANGUAGE'] = 'en'
         self.environ['LANG'] = 'en_US.UTF-8'
         self.environ['LC_MESSAGES'] = 'en_US.UTF-8'
         self.environ['LC_ALL'] = ''
 
-    # FIXME: This is a horrible, horrible hack for WinPort and should be removed.
-    # Maybe this belongs in Git in some more generic "find the git binary" codepath?
-    # Or possibly Executive should have a way to emulate shell path-lookups?
-    # FIXME: Unclear how to test this, since it currently mutates global state on Git.
-    def _engage_awesome_windows_hacks(self):
-        try:
-            self.executive.run_command(['git', 'help'])
-        except OSError:
-            try:
-                self.executive.run_command(['git.bat', 'help'])
-                # The Win port uses the depot_tools package, which contains a number
-                # of development tools, including Python and git. Instead of using a
-                # real git executable, depot_tools indirects via a batch file, called
-                # git.bat. This batch file allows depot_tools to auto-update the real
-                # git executable, which is contained in a subdirectory.
-                #
-                # That's all fine and good, except that subprocess.popen can detect
-                # the difference between a real git executable and batch file when we
-                # don't provide use shell=True. Rather than use shell=True on Windows,
-                # We hack the git.bat name into the SVN class.
-                _log.debug('Engaging git.bat Windows hack.')
-                Git.executable_name = 'git.bat'
-            except OSError:
-                _log.debug('Failed to engage git.bat Windows hack.')
-
-    def initialize_scm(self):
-        # TODO(qyearsley): Refactor this so that scm is initialized
-        # when self.scm() is called the first time; put any initialization
-        # code in the git module.
-        if sys.platform == 'win32':
-            self._engage_awesome_windows_hacks()
-
-        cwd = self.filesystem.abspath(self.filesystem.getcwd())
-        if Git.in_working_directory(cwd, executive=self.executive):
-            self._scm = Git(cwd=cwd, filesystem=self.filesystem, executive=self.executive)
-            return
-
-        script_directory = self.filesystem.abspath(
-            self.filesystem.dirname(self.filesystem.path_to_module(self.__module__)))
-        _log.info('The current directory (%s) is not in a git repo, trying script directory %s.', cwd, script_directory)
-        if Git.in_working_directory(script_directory, executive=self.executive):
-            self._scm = Git(cwd=script_directory, filesystem=self.filesystem, executive=self.executive)
-            return
-
-        raise Exception('FATAL: Failed to find Git repo for %s or %s' % (cwd, script_directory))
-
-    def scm(self,):
+    def scm(self, path=None):
+        if path:
+            return Git(cwd=path, executive=self.executive, filesystem=self.filesystem)
+        if not self._scm:
+            self._scm = Git(filesystem=self.filesystem, executive=self.executive)
         return self._scm
-
-    def scm_for_path(self, path):
-        # FIXME: make scm() be a wrapper around this, and clean up the way
-        # callers call initialize_scm() (to remove patch_directories) and scm().
-        if sys.platform == "win32":
-            self._engage_awesome_windows_hacks()
-        return Git(cwd=path, executive=self.executive, filesystem=self.filesystem)