Add server-side branch prefix search

src/VCS/Adapter/Git/GitHub.php

@@ -742,19 +742,42 @@ public function getPullRequestFromBranch(string $owner, string $repositoryName,
     }
 
     /**
-     * Lists branches for a given repository
+     * Lists branches for a given repository, optionally filtered by a search prefix.
      *
-     * @param  string  $owner Owner name of the repository
-     * @param  string  $repositoryName Name of the GitHub repository
-     * @param  int  $perPage Number of branches to fetch per page
-     * @param  int  $page Page number to start fetching from
-     * @return array<string> List of branch names as array
+     * When $search is provided, uses GET /repos/{owner}/{repo}/git/matching-refs/heads/{prefix}
+     * to perform server-side prefix filtering. This endpoint ignores per_page/page params and
+     * always returns all matching refs in one call; results are then paginated client-side.
+     * When $search is empty, uses GET /repos/{owner}/{repo}/branches with GitHub's native pagination.
+     *
+     * @param  string  $owner
+     * @param  string  $repositoryName
+     * @param  int  $perPage Clamped to [1, 100]
+     * @param  int  $page Page number (1-based)
+     * @param  string  $search Prefix filter; empty returns all branches
+     * @return array<string> List of branch names
      */
-    public function listBranches(string $owner, string $repositoryName, int $perPage = 100, int $page = 1): array
+    public function listBranches(string $owner, string $repositoryName, int $perPage = 100, int $page = 1, string $search = ''): array
     {
-        $url = "/repos/$owner/$repositoryName/branches";
         $perPage = min(max($perPage, 1), 100);
 
+        if ($search !== '') {
+            $url = "/repos/$owner/$repositoryName/git/matching-refs/heads/" . \str_replace('%2F', '/', \rawurlencode($search));
+            $response = $this->call(self::METHOD_GET, $url, ['Authorization' => "Bearer $this->accessToken"]);
+
+            $statusCode = $response['headers']['status-code'] ?? 0;
+            $responseBody = $response['body'] ?? [];
+
+            if ($statusCode < 200 || $statusCode >= 300 || !is_array($responseBody)) {
+                return [];
+            }
+
+            $branches = array_map(fn ($ref) => str_replace('refs/heads/', '', $ref['ref'] ?? ''), $responseBody);
+            $offset = ($page - 1) * $perPage;
+
+            return array_values(array_slice($branches, $offset, $perPage));
+        }
+
+        $url = "/repos/$owner/$repositoryName/branches";
         $response = $this->call(self::METHOD_GET, $url, ['Authorization' => "Bearer $this->accessToken"], [
             'page' => $page,
             'per_page' => $perPage,
@@ -831,15 +854,13 @@ public function getLatestCommit(string $owner, string $repositoryName, string $b
         $responseBody = $response['body'] ?? [];
         $responseBodyCommit = $responseBody['commit'] ?? [];
         $responseBodyCommitAuthor = $responseBodyCommit['author'] ?? [];
-        $responseBodyAuthor = $responseBody['author'] ?? [];
+        $responseBodyAuthor = is_array($responseBody['author'] ?? null) ? $responseBody['author'] : [];
 
         if (
             !array_key_exists('name', $responseBodyCommitAuthor) ||
             !array_key_exists('message', $responseBodyCommit) ||
             !array_key_exists('sha', $responseBody) ||
-            !array_key_exists('html_url', $responseBody) ||
-            !array_key_exists('avatar_url', $responseBodyAuthor) ||
-            !array_key_exists('html_url', $responseBodyAuthor)
+            !array_key_exists('html_url', $responseBody)
         ) {
             throw new Exception("Latest commit response is missing required information.");
         }

tests/VCS/Adapter/GitHubTest.php

@@ -548,6 +548,12 @@ public function testListBranchesPagination(): void
 
             $all = $adapter->listBranches(static::$owner, $repositoryName, 100, 1);
             $this->assertEqualsCanonicalizing([static::$defaultBranch, 'branch-a', 'branch-b'], $all);
+
+            $searchResults = $adapter->listBranches(static::$owner, $repositoryName, 100, 1, 'branch');
+            $this->assertEqualsCanonicalizing(['branch-a', 'branch-b'], $searchResults);
+
+            $noMatch = $adapter->listBranches(static::$owner, $repositoryName, 100, 1, 'xyz');
+            $this->assertEmpty($noMatch);
         } finally {
             $this->vcsAdapter->deleteRepository(static::$owner, $repositoryName);
         }