Fix git push in new worktrees (#13)

When creating a new worktree with a new branch, git push would fail
because no upstream was configured. Users had to manually run 'git push
-u origin <branch>' every time.

This fix adds a new function `configure_push_remote()` that sets the
branch's remote and merge configuration even before the remote branch
exists. This allows 'git push' to work automatically without requiring
the -u flag.

Changes:
- Added git.configure_push_remote() to set branch.{branch}.remote and
branch.{branch}.merge
- Updated worktree creation to use configure_push_remote() for new
branches
- For existing branches, check if remote exists and use appropriate
method
- Added test coverage for the new function

Closes: Worktree git push configuration issue

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: 3 people

tools/wt-worktree/tests/test_git.py

@@ -143,3 +143,19 @@ def test_diff_trees(git_repo):
     # Get diff
     diff = git.diff_trees("HEAD~1", "HEAD", git_repo)
     assert "file2.txt" in diff
+
+
+def test_configure_push_remote(git_repo):
+    """Test configuring push remote for a branch."""
+    # Create a new branch
+    git.create_branch("test-branch", "HEAD", git_repo)
+
+    # Configure push remote
+    git.configure_push_remote("test-branch", "origin", "test-branch", git_repo)
+
+    # Verify configuration was set
+    result = git.run_git(["config", "branch.test-branch.remote"], cwd=git_repo)
+    assert result.stdout.strip() == "origin"
+
+    result = git.run_git(["config", "branch.test-branch.merge"], cwd=git_repo)
+    assert result.stdout.strip() == "refs/heads/test-branch"

tools/wt-worktree/wt/git.py

@@ -160,6 +160,30 @@ def set_upstream(branch: str, remote: str = "origin",
     run_git(["branch", f"--set-upstream-to={remote}/{remote_branch}", branch], cwd=path)
 
 
+def configure_push_remote(branch: str, remote: str = "origin",
+                         remote_branch: Optional[str] = None, path: Optional[Path] = None):
+    """
+    Configure where a branch should push to, even if remote branch doesn't exist yet.
+
+    This sets branch.{branch}.remote and branch.{branch}.merge so that 'git push'
+    will work without needing to specify the remote or use -u flag.
+
+    Args:
+        branch: Local branch name
+        remote: Remote name
+        remote_branch: Remote branch name (defaults to same as local)
+        path: Repository path to run git commands in
+    """
+    if remote_branch is None:
+        remote_branch = branch
+
+    # Set the remote
+    run_git(["config", f"branch.{branch}.remote", remote], cwd=path)
+
+    # Set the merge target (what the branch tracks/pushes to)
+    run_git(["config", f"branch.{branch}.merge", f"refs/heads/{remote_branch}"], cwd=path)
+
+
 def list_worktrees(path: Optional[Path] = None) -> List[dict]:
     """
     List all worktrees.

tools/wt-worktree/wt/worktree.py

@@ -170,15 +170,25 @@ def create_worktree(self, name: str, base: Optional[str] = None,
         except git.GitError as e:
             raise git.GitError(f"Failed to create worktree: {e}")
 
-        # Set upstream tracking if not detached
-        if not detached:
+        # Configure push remote if not detached
+        if not detached and create_branch:
             try:
-                # Set upstream to origin/<branch>
-                remote_branch = branch
-                git.set_upstream(branch, "origin", remote_branch, self.repo_root)
+                # For new branches, configure where to push (so git push works without -u)
+                # This works even if remote branch doesn't exist yet
+                git.configure_push_remote(branch, "origin", branch, wt_path)
             except git.GitError:
-                # Upstream setting might fail if remote doesn't exist yet
-                # This is okay, user can push later
+                # If this fails, user can still push with -u flag
+                pass
+        elif not detached:
+            try:
+                # For existing branches, check if remote branch exists and set upstream
+                if git.remote_branch_exists(branch, "origin", self.repo_root):
+                    git.set_upstream(branch, "origin", branch, self.repo_root)
+                else:
+                    # Remote doesn't exist yet, configure push target instead
+                    git.configure_push_remote(branch, "origin", branch, wt_path)
+            except git.GitError:
+                # If this fails, user can still push with -u flag
                 pass
 
         return wt_path