[6.x] Prevent overlapping git commit jobs

config/git.php

@@ -62,6 +62,20 @@
 
     'dispatch_delay' => env('STATAMIC_GIT_DISPATCH_DELAY', 0),
 
+    /*
+    |--------------------------------------------------------------------------
+    | Unique Lock Expiry
+    |--------------------------------------------------------------------------
+    |
+    | When commits are queued, a unique lock prevents multiple jobs from
+    | running concurrently against the same repository. This value (in
+    | seconds) controls how long that lock is held as a crash-safety
+    | net. It should exceed your queue worker's configured timeout.
+    |
+    */
+
+    'unique_lock_expiry' => env('STATAMIC_GIT_UNIQUE_LOCK_EXPIRY', 120),
+
     /*
     |--------------------------------------------------------------------------
     | Git User

src/Git/CommitJob.php

@@ -3,27 +3,45 @@
 namespace Statamic\Git;
 
 use Illuminate\Bus\Queueable;
+use Illuminate\Contracts\Queue\ShouldBeUnique;
 use Illuminate\Contracts\Queue\ShouldQueue;
 use Illuminate\Foundation\Bus\Dispatchable;
 use Illuminate\Queue\InteractsWithQueue;
+use Illuminate\Support\Facades\Cache;
 use Statamic\Facades\Git;
 
-class CommitJob implements ShouldQueue
+use function Statamic\trans as __;
+
+class CommitJob implements ShouldBeUnique, ShouldQueue
 {
     use Dispatchable, InteractsWithQueue, Queueable;
 
+    public int $uniqueFor;
+
     /**
      * Create a new job instance.
      */
     public function __construct(public $message = null, public $committer = null)
     {
+        $this->uniqueFor = config('statamic.git.unique_lock_expiry', 120);
     }
 
     /**
      * Execute the job.
      */
     public function handle()
     {
-        Git::as($this->committer)->commit($this->message);
+        $saves = Cache::pull('statamic-git-pending-saves', []);
+        $users = collect($saves)->unique('email')->values();
+        $coalesced = $users->count() > 1;
+
+        $message = $this->message;
+
+        if ($coalesced) {
+            $trailers = $users->map(fn ($u) => "Co-Authored-By: {$u['name']} <{$u['email']}>")->implode("\n");
+            $message = ($message ?? __('Content saved'))."\n\n".$trailers;
+        }
+
+        Git::as($coalesced ? null : $this->committer)->commit($message);
     }
 }

src/Git/Git.php

@@ -4,6 +4,7 @@
 
 use Illuminate\Filesystem\Filesystem;
 use Illuminate\Support\Collection;
+use Illuminate\Support\Facades\Cache;
 use Statamic\Console\Processes\Git as GitProcess;
 use Statamic\Contracts\Auth\User as UserContract;
 use Statamic\Facades\Antlers;
@@ -93,6 +94,10 @@ public function dispatchCommit($message = null)
             $message = null;
         }
 
+        $saves = Cache::get('statamic-git-pending-saves', []);
+        $saves[] = ['name' => $this->gitUserName(), 'email' => $this->gitUserEmail()];
+        Cache::put('statamic-git-pending-saves', $saves);
+
         CommitJob::dispatch($message, $this->authenticatedUser())
             ->onConnection(config('statamic.git.queue_connection'))
             ->delay($delayInMinutes ?? null);
@@ -283,8 +288,11 @@ protected function shellEscape(string $string)
     {
         $string = str_replace('"', '', $string);
         $string = str_replace("'", '', $string);
+        $string = str_replace('\\', '\\\\', $string);
+        $string = str_replace('$', '\\$', $string);
+        $string = str_replace('`', '\\`', $string);
 
-        return escapeshellcmd($string);
+        return $string;
     }
 
     /**

tests/Git/GitTest.php

@@ -3,6 +3,7 @@
 namespace Tests\Git;
 
 use Illuminate\Filesystem\Filesystem;
+use Illuminate\Support\Facades\Cache;
 use Illuminate\Support\Facades\Queue;
 use PHPUnit\Framework\Attributes\Test;
 use Statamic\Console\Processes\Git as GitProcess;
@@ -252,13 +253,8 @@ public function it_shell_escapes_git_user_name_and_email()
 
         Git::commit('Message"; echo "deleting all your files now"; #');
 
-        $expectedUser = 'Jimmy\; echo deleting all your files now\; \# <jimmy@haxor.org\; echo deleting all your files now\; \#>';
-        $expectedMessage = 'Message\; echo deleting all your files now\; \#';
-
-        if (static::isRunningWindows()) {
-            $expectedUser = str_replace('\\', '^', $expectedUser);
-            $expectedMessage = str_replace('\\', '^', $expectedMessage);
-        }
+        $expectedUser = 'Jimmy; echo deleting all your files now; # <jimmy@haxor.org; echo deleting all your files now; #>';
+        $expectedMessage = 'Message; echo deleting all your files now; #';
 
         $lastCommit = $this->showLastCommit(base_path('content'));
 
@@ -400,6 +396,115 @@ public function it_dispatches_commit_job()
         Queue::assertPushed(\Statamic\Git\CommitJob::class, 1);
     }
 
+    #[Test]
+    public function it_only_dispatches_one_commit_job_at_a_time()
+    {
+        // ShouldBeUnique acquires its cache lock in Bus\Dispatcher before the job
+        // reaches the queue driver, so Queue::fake() still enforces uniqueness here.
+        Queue::fake();
+
+        Git::dispatchCommit();
+        Git::dispatchCommit();
+        Git::dispatchCommit();
+
+        Queue::assertPushed(\Statamic\Git\CommitJob::class, 1);
+    }
+
+    #[Test]
+    public function it_attributes_coalesced_commits_to_the_configured_user()
+    {
+        Cache::put('statamic-git-pending-saves', [
+            ['name' => 'Alice', 'email' => 'alice@example.com'],
+            ['name' => 'Bob', 'email' => 'bob@example.com'],
+        ]);
+
+        $user = User::make()->email('alice@example.com');
+
+        Git::shouldReceive('as')->with(null)->andReturnSelf()->once();
+        Git::shouldReceive('commit')->withArgs(function ($message) {
+            return str_contains($message, 'Entry saved')
+                && str_contains($message, 'Co-Authored-By: Alice <alice@example.com>')
+                && str_contains($message, 'Co-Authored-By: Bob <bob@example.com>');
+        })->once();
+
+        (new \Statamic\Git\CommitJob('Entry saved', $user))->handle();
+    }
+
+    #[Test]
+    public function it_attributes_non_coalesced_commits_to_the_authenticated_user()
+    {
+        Cache::put('statamic-git-pending-saves', [
+            ['name' => 'Alice', 'email' => 'alice@example.com'],
+        ]);
+
+        $user = User::make()->email('alice@example.com');
+
+        Git::shouldReceive('as')->with($user)->andReturnSelf()->once();
+        Git::shouldReceive('commit')->with('Entry saved')->once();
+
+        (new \Statamic\Git\CommitJob('Entry saved', $user))->handle();
+    }
+
+    #[Test]
+    public function it_adds_co_authored_by_trailers_for_coalesced_saves()
+    {
+        $this->files->put(base_path('content/collections/pages.yaml'), 'title: Pages Title Changed');
+
+        $message = "Content saved\n\nCo-Authored-By: Alice <alice@example.com>\nCo-Authored-By: Bob <bob@example.com>";
+
+        Git::commit($message);
+
+        $commit = $this->showLastCommit(base_path('content'));
+
+        $this->assertStringContainsString('Co-Authored-By: Alice <alice@example.com>', $commit);
+        $this->assertStringContainsString('Co-Authored-By: Bob <bob@example.com>', $commit);
+    }
+
+    #[Test]
+    public function it_deduplicates_co_authors_for_repeated_saves_by_the_same_user()
+    {
+        Cache::put('statamic-git-pending-saves', [
+            ['name' => 'Alice', 'email' => 'alice@example.com'],
+            ['name' => 'Alice', 'email' => 'alice@example.com'],
+            ['name' => 'Bob', 'email' => 'bob@example.com'],
+        ]);
+
+        $user = User::make()->email('alice@example.com');
+
+        Git::shouldReceive('as')->with(null)->andReturnSelf()->once();
+        Git::shouldReceive('commit')->withArgs(function ($message) {
+            return substr_count($message, 'Co-Authored-By:') === 2
+                && str_contains($message, 'Co-Authored-By: Alice <alice@example.com>')
+                && str_contains($message, 'Co-Authored-By: Bob <bob@example.com>');
+        })->once();
+
+        (new \Statamic\Git\CommitJob('Entry saved', $user))->handle();
+    }
+
+    #[Test]
+    public function it_wires_dispatch_to_co_authored_by_trailers_end_to_end()
+    {
+        Queue::fake();
+
+        $this->files->put(base_path('content/collections/pages.yaml'), 'title: Pages Title Changed');
+
+        $alice = User::make()->email('alice@example.com')->data(['name' => 'Alice'])->makeSuper();
+        $bob = User::make()->email('bob@example.com')->data(['name' => 'Bob'])->makeSuper();
+
+        $this->actingAs($alice);
+        Git::dispatchCommit();
+
+        $this->actingAs($bob);
+        Git::dispatchCommit(); // dropped by ShouldBeUnique, but Bob's save is still recorded in cache
+
+        (new \Statamic\Git\CommitJob(null, $alice))->handle();
+
+        $commit = $this->showLastCommit(base_path('content'));
+
+        $this->assertStringContainsString('Co-Authored-By: Alice <alice@example.com>', $commit);
+        $this->assertStringContainsString('Co-Authored-By: Bob <bob@example.com>', $commit);
+    }
+
     #[Test]
     public function it_doesnt_push_by_default()
     {