Initial Contribution

editor.py

@@ -0,0 +1,85 @@
+#
+# Copyright (C) 2008 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+import sys
+import subprocess
+import tempfile
+
+from error import EditorError
+
+class Editor(object):
+  """Manages the user's preferred text editor."""
+
+  _editor = None
+  globalConfig = None
+
+  @classmethod
+  def _GetEditor(cls):
+    if cls._editor is None:
+      cls._editor = cls._SelectEditor()
+    return cls._editor
+
+  @classmethod
+  def _SelectEditor(cls):
+    e = os.getenv('GIT_EDITOR')
+    if e:
+      return e
+
+    e = cls.globalConfig.GetString('core.editor')
+    if e:
+      return e
+
+    e = os.getenv('VISUAL')
+    if e:
+      return e
+
+    e = os.getenv('EDITOR')
+    if e:
+      return e
+
+    if os.getenv('TERM') == 'dumb':
+      print >>sys.stderr,\
+"""No editor specified in GIT_EDITOR, core.editor, VISUAL or EDITOR.
+Tried to fall back to vi but terminal is dumb.  Please configure at
+least one of these before using this command."""
+      sys.exit(1)
+
+    return 'vi'
+
+  @classmethod
+  def EditString(cls, data):
+    """Opens an editor to edit the given content.
+
+       Args:
+         data        : the text to edit
+  
+      Returns:
+        new value of edited text; None if editing did not succeed
+    """
+    editor = cls._GetEditor()
+    fd, path = tempfile.mkstemp()
+    try:
+      os.write(fd, data)
+      os.close(fd)
+      fd = None
+
+      if subprocess.Popen([editor, path]).wait() != 0:
+        raise EditorError()
+      return open(path).read()
+    finally:
+      if fd:
+        os.close(fd)
+      os.remove(path)