diff -r 000000000000 -r 4f2f89ce4247 WebKitTools/Scripts/webkitpy/tool/steps/abstractstep.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebKitTools/Scripts/webkitpy/tool/steps/abstractstep.py	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,85 @@
+# Copyright (C) 2010 Google 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
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# 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.
+
+from webkitpy.common.system.deprecated_logging import log
+from webkitpy.common.system.executive import ScriptError
+from webkitpy.common.config.ports import WebKitPort
+from webkitpy.tool.steps.options import Options
+
+
+class AbstractStep(object):
+    def __init__(self, tool, options):
+        self._tool = tool
+        if options.no_squash:
+            raise ScriptError('--no-squash has been removed. Use "--git-commit=HEAD.." or "-g HEAD.." to operate on the working copy.')
+        if options.squash:
+            raise ScriptError('--squash has been removed. It is now the default behavior if --git-commit is omitted.')
+        self._options = options
+        self._port = None
+
+    def _run_script(self, script_name, args=None, quiet=False, port=WebKitPort):
+        log("Running %s" % script_name)
+        command = [port.script_path(script_name)]
+        if args:
+            command.extend(args)
+        # FIXME: This should use self.port()
+        self._tool.executive.run_and_throw_if_fail(command, quiet)
+
+    # FIXME: The port should live on the tool.
+    def port(self):
+        if self._port:
+            return self._port
+        self._port = WebKitPort.port(self._options.port)
+        return self._port
+
+    _well_known_keys = {
+        "diff": lambda self, state: self._tool.scm().create_patch(self._options.git_commit),
+        "changelogs": lambda self, state: self._tool.checkout().modified_changelogs(self._options.git_commit),
+        "bug_title": lambda self, state: self._tool.bugs.fetch_bug(state["bug_id"]).title(),
+    }
+
+    def cached_lookup(self, state, key, promise=None):
+        if state.get(key):
+            return state[key]
+        if not promise:
+            promise = self._well_known_keys.get(key)
+        state[key] = promise(self, state)
+        return state[key]
+
+    @classmethod
+    def options(cls):
+        return [
+            # We need this option here because cached_lookup uses it.  :(
+            Options.git_commit,
+            # FIXME: Get rid of these.
+            Options.no_squash,
+            Options.squash,
+        ]
+
+    def run(self, state):
+        raise NotImplementedError, "subclasses must implement"