fix(git): include remote-only branches from ls-remote in branch lists (#2735)

fix(git): include remote-only branches from ls-remote in branch lists

packages/web/server/lib/git/DOCUMENTATION.md

@@ -121,7 +121,7 @@ The following functions are internal helpers used by exported functions:
 - `rebaseInProgress`: Object with `{ headName, onto }` if rebase in progress.
 
 ### Branches Response
-- `all`: Local branches plus remote-tracking branches that still exist on their remote. A remote that fails to answer keeps its branches in the list: "we could not ask" must not be reported as "these branches are gone", because callers use this list to decide whether a base branch exists at all.
+- `all`: Local branches plus every branch each reachable remote reports via `ls-remote --heads`, formatted as `remotes/<remote>/<branch>`. This is a union: local remote-tracking refs deleted on the remote are pruned, and branches that exist on the remote without a local tracking ref (never fetched) are still included, so a freshly pushed branch appears without requiring a fetch. A remote that fails to answer keeps its locally known branches in the list: "we could not ask" must not be reported as "these branches are gone", because callers use this list to decide whether a base branch exists at all.
 - `current`: Current branch name.
 - `branches`: Per-branch detail keyed by branch name, as reported by `git branch`.
 - `defaultBranches`: Each remote's default branch, keyed by remote name. Read from the local `remotes/<name>/HEAD` symbolic ref; for a remote that has none — clone writes it, a hand-added remote may not — the remote itself is asked once with `ls-remote --symref`. A remote that answers neither is absent rather than guessed, and consumers fall back to conventional branch names. Omitted entirely by runtimes that do not provide this Git metadata.

packages/web/server/lib/git/service.js

@@ -3747,7 +3747,7 @@ async function filterActiveRemoteBranches(git, remoteBranches) {
       }
     }));
 
-    return remoteBranches.filter(remoteBranch => {
+    const activeBranches = remoteBranches.filter(remoteBranch => {
       const match = remoteBranch.match(/^remotes\/[^\/]+\/(.+)$/);
       if (!match) return false;
       const remoteName = remoteBranch.split('/')[1];
@@ -3755,6 +3755,25 @@ async function filterActiveRemoteBranches(git, remoteBranches) {
       if (unreachableRemotes.has(remoteName)) return true;
       return branchesByRemote.get(remoteName)?.has(branchName) ?? false;
     });
+
+    // A branch pushed to the remote that was never fetched locally has no
+    // remote-tracking ref, so `git branch` never reports it — but ls-remote
+    // just told us it exists. Add those so a freshly pushed branch shows up
+    // without requiring a fetch first (#2098). Unreachable remotes have no
+    // ls-remote data and therefore add nothing here; their local view above
+    // is preserved unchanged.
+    const seenBranches = new Set(activeBranches);
+    for (const [remoteName, actualRemoteBranches] of branchesByRemote) {
+      for (const branchName of actualRemoteBranches) {
+        const qualifiedBranch = `remotes/${remoteName}/${branchName}`;
+        if (!seenBranches.has(qualifiedBranch)) {
+          seenBranches.add(qualifiedBranch);
+          activeBranches.push(qualifiedBranch);
+        }
+      }
+    }
+
+    return activeBranches;
   } catch (error) {
     console.warn('Failed to filter active remote branches, returning all:', error.message);
     return remoteBranches;

packages/web/server/lib/git/service.test.js

@@ -1429,6 +1429,47 @@ describe.runIf(canRunGit())('getBranches', () => {
     // decide whether a base branch exists at all.
     expect(branches.all).toContain('remotes/origin/react');
   });
+
+  it('includes remote branches with no local tracking ref and prunes refs deleted on the remote (#2098)', async () => {
+    const remote = createTempDir();
+    runGit(remote, ['init', '--bare', '--initial-branch=main']);
+
+    const repository = createTempDir();
+    runGit(repository, ['init', '-b', 'main']);
+    runGit(repository, ['config', 'user.email', 'test@example.com']);
+    runGit(repository, ['config', 'user.name', 'Test']);
+    fs.writeFileSync(path.join(repository, 'README.md'), '# Test\n');
+    runGit(repository, ['add', 'README.md']);
+    runGit(repository, ['commit', '-m', 'init']);
+    runGit(repository, ['remote', 'add', 'origin', remote]);
+    runGit(repository, ['push', '-u', 'origin', 'main']);
+    runGit(repository, ['checkout', '-b', 'feature-known']);
+    runGit(repository, ['push', '-u', 'origin', 'feature-known']);
+    // This tracking ref will go stale: the collaborator deletes the branch on
+    // the remote below, and the list must prune it.
+    runGit(repository, ['checkout', '-b', 'feature-stale']);
+    runGit(repository, ['push', '-u', 'origin', 'feature-stale']);
+    runGit(repository, ['checkout', 'main']);
+    runGit(repository, ['branch', '-D', 'feature-stale']);
+
+    // A collaborator pushes a branch straight to the remote and deletes
+    // another; this repository never fetches, so it has no local
+    // remote-tracking ref for feature-remote-only.
+    const collaborator = createTempDir();
+    runGit(collaborator, ['clone', remote, '.']);
+    runGit(collaborator, ['config', 'user.email', 'test@example.com']);
+    runGit(collaborator, ['config', 'user.name', 'Test']);
+    runGit(collaborator, ['checkout', '-b', 'feature-remote-only']);
+    runGit(collaborator, ['push', 'origin', 'feature-remote-only']);
+    runGit(collaborator, ['push', 'origin', ':feature-stale']);
+
+    const branches = await getBranches(repository);
+
+    expect(branches.all).toContain('remotes/origin/feature-remote-only');
+    expect(branches.all).toContain('remotes/origin/feature-known');
+    expect(branches.all).toContain('feature-known');
+    expect(branches.all).not.toContain('remotes/origin/feature-stale');
+  });
 });
 
 describe.runIf(canRunGit())('getRangeDiff', () => {