Merge pull request #380 from VariousForks/message_as_file_with_unittest

aider/main.py

@@ -380,6 +380,12 @@ def main(argv=None, input=None, output=None, force_git_root=None):
         metavar="COMMAND",
         help="Specify a single message to send GPT, process reply then exit (disables chat mode)",
     )
+    other_group.add_argument(
+        "--message-file",
+        "-f",
+        metavar="MESSAGE_FILE",
+        help="Specify a file containing the message to send GPT, process reply, then exit (disables chat mode)",
+    )
     other_group.add_argument(
         "--encoding",
         default="utf-8",
@@ -563,6 +569,17 @@ def main(argv=None, input=None, output=None, force_git_root=None):
         io.add_to_input_history(args.message)
         io.tool_output()
         coder.run(with_message=args.message)
+    elif args.message_file:
+        try:
+            message_from_file = io.read_text(args.message_file)
+            io.tool_output()
+            coder.run(with_message=message_from_file)
+        except FileNotFoundError:
+            io.tool_error(f"Message file not found: {args.message_file}")
+            return 1
+        except IOError as e:
+            io.tool_error(f"Error reading message file: {e}")
+            return 1
     else:
         coder.run()
 

tests/test_main.py

@@ -182,6 +182,19 @@ class TestMain(TestCase):
             _, kwargs = MockCoder.call_args
             assert kwargs["dirty_commits"] is True
 
+    def test_message_file_flag(self):
+        message_file_content = "This is a test message from a file."
+        message_file_path = tempfile.mktemp()
+        with open(message_file_path, 'w', encoding='utf-8') as message_file:
+            message_file.write(message_file_content)
+
+        with patch("aider.main.Coder.create") as MockCoder:
+            MockCoder.return_value.run = MagicMock()
+            main(["--yes", "--message-file", message_file_path], input=DummyInput(), output=DummyOutput())
+            MockCoder.return_value.run.assert_called_once_with(with_message=message_file_content)
+
+        os.remove(message_file_path)
+
     def test_encodings_arg(self):
         fname = "foo.py"