Make submit work with 'git rebase -i'

src/stack_pr/cli.py

@@ -51,6 +51,7 @@
 
 import argparse
 import configparser
+import contextlib
 import json
 import logging
 import os
@@ -526,6 +527,24 @@ def draft_bitmask_type(value: str) -> list[bool]:
     return [bool(int(bit)) for bit in value]
 
 
+@contextlib.contextmanager
+def maybe_stash_interactive_rebase() -> Iterator[None]:
+    """
+    If the user is in the middle of an interactive rebase, we stash the
+    rebase state so that we can restore it later. This is useful when
+    the user is trying to submit only part of their commit history.
+    """
+    if os.path.exists(".git/rebase-merge"):
+        try:
+            assert not os.path.exists(".git/rebase-merge-stashed")
+            os.rename(".git/rebase-merge", ".git/rebase-merge-stashed")
+            yield
+        finally:
+            os.rename(".git/rebase-merge-stashed", ".git/rebase-merge")
+    else:
+        yield
+
+
 # ===----------------------------------------------------------------------=== #
 # SUBMIT
 # ===----------------------------------------------------------------------=== #
@@ -1500,13 +1519,14 @@ def main() -> None:  # noqa: PLR0912
         common_args = deduce_base(common_args)
 
         if args.command in ["submit", "export"]:
-            command_submit(
-                common_args,
-                draft=args.draft,
-                reviewer=args.reviewer,
-                keep_body=args.keep_body,
-                draft_bitmask=args.draft_bitmask,
-            )
+            with maybe_stash_interactive_rebase():
+                command_submit(
+                    common_args,
+                    draft=args.draft,
+                    reviewer=args.reviewer,
+                    keep_body=args.keep_body,
+                    draft_bitmask=args.draft_bitmask,
+                )
         elif args.command == "land":
             command_land(common_args)
         elif args.command == "abandon":

src/stack_pr/git.py

@@ -83,7 +83,7 @@ def get_current_branch_name(repo_dir: Path | None = None) -> str:
         repo_dir: path to the repo. Defaults to the current working directory.
 
     Returns:
-        The name of the branch currently checked out, or "HEAD" if the repo is
+        The name of the branch currently checked out, or a hash if the repo is
         in a 'detached HEAD' state
 
     Raises:
@@ -92,9 +92,17 @@ def get_current_branch_name(repo_dir: Path | None = None) -> str:
     """
 
     try:
-        return get_command_output(
+        result = get_command_output(
             ["git", "rev-parse", "--abbrev-ref", "HEAD"], cwd=repo_dir
         ).strip()
+        if result == "HEAD":
+            # Detached HEAD state, return a hash so we can cleanup after ourselves properly, since
+            #    git checkout HEAD
+            # is a no-op.
+            result = get_command_output(
+                ["git", "rev-parse", "HEAD"], cwd=repo_dir
+            ).strip()
+        return result
     except subprocess.CalledProcessError as e:
         if e.returncode == GIT_NOT_A_REPO_ERROR:
             raise GitError("Not inside a valid git repository.") from e

src/stack_pr/shell_commands.py

@@ -45,7 +45,8 @@ def run_shell_command(
         raise ValueError("shell support has been removed")
     _ = subprocess.list2cmdline(cmd)
     if quiet:
-        kwargs.update({"stdout": subprocess.DEVNULL, "stderr": subprocess.DEVNULL})
+        # Use pipes so errors result in usable error messages
+        kwargs.update({"stdout": subprocess.PIPE, "stderr": subprocess.PIPE})
     logger.debug("Running: %s", cmd)
     return subprocess.run(list(map(str, cmd)), **kwargs, check=check)