chore: rework error message (#573)

Author: sileht

mergify_cli/stack/push.py

@@ -65,7 +65,7 @@ def format_pull_description(
 
 # TODO(charly): fix code to conform to linter (number of arguments, local
 # variables, statements, positional arguments, branches)
-async def stack_push(  # noqa: PLR0912, PLR0913, PLR0915, PLR0917
+async def stack_push(  # noqa: PLR0912, PLR0913, PLR0915, PLR0917, PLR0914
     github_server: str,
     token: str,
     skip_rebase: bool,
@@ -105,7 +105,14 @@ async def stack_push(  # noqa: PLR0912, PLR0913, PLR0915, PLR0917
     )
 
     if base_branch == dest_branch:
-        console.log("[red] base branch and destination branch are the same [/]")
+        remote_url = await utils.git("remote", "get-url", remote)
+        console.print(
+            f"Your local branch `{dest_branch}` targets itself: `{remote}/{base_branch}` (at {remote_url}@{base_branch}).\n"
+            f"You should either fix the target branch or rename your local branch.\n\n"
+            f"* To fix the target branch: `git branch {dest_branch} --set-upstream-to={remote}/main>\n",
+            f"* To rename your local branch: `git branch -M {dest_branch} new-branch-name`",
+            style="red",
+        )
         sys.exit(1)
 
     stack_prefix = f"{branch_prefix}/{dest_branch}" if branch_prefix else dest_branch

mergify_cli/tests/stack/test_push.py

@@ -487,6 +487,12 @@ async def test_stack_on_destination_branch_raises_an_error(
 ) -> None:
     respx_mock.get("/user").respond(200, json={"login": "author"})
     git_mock.mock("rev-parse", "--abbrev-ref", "HEAD", output="main")
+    git_mock.mock(
+        "remote",
+        "get-url",
+        "origin",
+        output="https://github.com/foo/bar.git",
+    )
 
     with pytest.raises(SystemExit, match="1"):
         await push.stack_push(