macOS: fix args passed via open --args being ignored when macos-launch-services-cmdline is present (fixes #9910)

Agent-Logs-Url: https://github.com/kovidgoyal/kitty/sessions/2cdc7e8f-5b64-4c97-bd65-dec508155313

Co-authored-by: kovidgoyal <1308621+kovidgoyal@users.noreply.github.com>

docs/changelog.rst

@@ -259,6 +259,8 @@ Detailed list of changes
 
 - Fix setting :opt:`momentum_scroll` to zero not *fully* disabling momentum scrolling (:iss:`9904`)
 
+- macOS: Fix args passed via ``open --args`` being ignored when :file:`macos-launch-services-cmdline` is present (:iss:`9910`)
+
 
 0.46.2 [2026-03-21]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

kitty/launcher/cmdline.c

@@ -13,6 +13,24 @@
 #include <os/log.h>
 #endif
 
+bool
+append_arg_to_argv_array(argv_array *a, const char *arg) {
+    if (a->count + 2 > a->capacity) {
+        size_t cap = a->capacity * 2;
+        if (!cap) cap = 256;
+        void *m = realloc(a->argv, cap * sizeof(a->argv[0]));
+        if (!m) return false;
+        a->argv = m;
+        a->capacity = cap;
+        a->needs_free = true;
+    }
+    // arg points into the process's original argv which persists for the lifetime
+    // of the process and is never modified through this pointer.
+    a->argv[a->count++] = (char*)arg;
+    a->argv[a->count] = 0;
+    return true;
+}
+
 void
 free_argv_array(argv_array *a) {
     if (a && a->needs_free) {

kitty/launcher/launcher.h

@@ -25,4 +25,5 @@ typedef struct argv_array {
 
 void single_instance_main(int argc, char *argv[], const CLIOptions *opts);
 bool get_argv_from(const char *filename, const char* argv0, argv_array *ans);
+bool append_arg_to_argv_array(argv_array *a, const char *arg);
 void free_argv_array(argv_array *a);

kitty/launcher/main.c

@@ -539,7 +539,19 @@ main(int argc_, char *argv_[], char* envp[]) {
         if (launched_by_launch_services && config_dir[0]) {
             char cbuf[PATH_MAX];
             safe_snprintf(cbuf, sizeof(cbuf), "%s/macos-launch-services-cmdline", config_dir);
+            int orig_argc = argc_; char **orig_argv = argv_;
             if (!get_argv_from(cbuf, argva.argv[0], &argva)) exit(1);
+            // If the file was loaded (argva replaced), append any extra args passed via open --args
+            if (argva.needs_free) {
+                for (int i = 1; i < orig_argc; i++) {
+                    // Skip Apple-internal process serial number args (-psn_*)
+                    if (strncmp(orig_argv[i], "-psn_", sizeof("-psn_") - 1) == 0) continue;
+                    if (!append_arg_to_argv_array(&argva, orig_argv[i])) {
+                        fprintf(stderr, "Out of memory while processing launch services args\n");
+                        exit(1);
+                    }
+                }
+            }
         }
     }
 #else

kitty_tests/datatypes.py

@@ -650,19 +650,26 @@ class TestDataTypes(BaseTest):
                 shutil.rmtree(dot_config)
             with tempfile.TemporaryDirectory() as tdir:
                 with open(tdir + '/macos-launch-services-cmdline', 'w') as f:
-                    print('kitty +runpy "import sys; print(sys.argv[-1])"', file=f)
-                    print('next-line', file=f)
-                    print()
+                    print('kitty --title from-file', file=f)
                 if is_macos:
                     env = os.environ.copy()
                     env['KITTY_CONFIG_DIRECTORY'] = tdir
                     env['KITTY_LAUNCHED_BY_LAUNCH_SERVICES'] = '1'
-                    cp = subprocess.run([kitty_exe(), '+runpy', 'import json, sys; print(json.dumps(sys.argv))'], env=env, stdout=subprocess.PIPE)
-                    actual = cp.stdout.strip().decode()
+                    # Test 1: file args are loaded when no extra user args are present
+                    cp = subprocess.run([kitty_exe(), '+testing-launcher-code'], env=env, stdout=subprocess.PIPE)
+                    actual = cp.stdout.decode()
                     if cp.returncode != 0:
                         print(actual)
-                        raise AssertionError(f'kitty +runpy failed with return code: {cp.returncode}')
-                    self.ae('next-line', actual)
+                        raise AssertionError(f'kitty +testing-launcher-code failed with return code: {cp.returncode}')
+                    self.assertIn('from-file', actual)
+                    # Test 2: extra args passed via open --args are appended after file args
+                    cp = subprocess.run([kitty_exe(), '+testing-launcher-code', '--title', 'from-args'], env=env, stdout=subprocess.PIPE)
+                    actual = cp.stdout.decode()
+                    if cp.returncode != 0:
+                        print(actual)
+                        raise AssertionError(f'kitty +testing-launcher-code failed with return code: {cp.returncode}')
+                    # from-args overrides from-file because user args are appended after file args
+                    self.assertIn('from-args', actual)
                 os.makedirs(tdir + '/good/kitty')
                 open(tdir + '/good/kitty/kitty.conf', 'w').close()
                 data = os.urandom(32879)

kitty_tests/options.py

@@ -125,14 +125,18 @@ version
 
 
 def launcher(self):
+    import tempfile
+    from kitty.constants import is_macos
     kexe = kitty_exe()
     cfgdir = None
-    def get_report(cmdline: str, launch_services= False):
+    def get_report(cmdline: str, launch_services= False, config_dir: str = ''):
         nonlocal cfgdir
         args = list(shlex_split(cmdline))
         env = dict(os.environ)
         if launch_services:
             env['KITTY_LAUNCHED_BY_LAUNCH_SERVICES'] = '1'
+        if config_dir:
+            env['KITTY_CONFIG_DIRECTORY'] = config_dir
         cp = subprocess.run([kexe, "+testing-launcher-code"] + args, env=env, stdout=subprocess.PIPE)
         self.assertEqual(cp.returncode, 0)
         ans = {}
@@ -200,6 +204,17 @@ def launcher(self):
     dt('--detach --session=moose --detached-log=xyz', detached_log='xyz', session='moose')
     pn('+kitten panel -1 --edge=left', edge='left')
 
+    if is_macos:
+        with tempfile.TemporaryDirectory() as tdir:
+            with open(tdir + '/macos-launch-services-cmdline', 'w') as f:
+                f.write('kitty --title from-file\n')
+            # File args are used when launched by launch services
+            r, output = get_report('', launch_services=True, config_dir=tdir)
+            self.assertEqual(r.get('title'), 'from-file', f'Expected title=from-file in:\n{output}')
+            # User args passed via open --args are appended after file args (and override them)
+            r, output = get_report('--title from-args', launch_services=True, config_dir=tdir)
+            self.assertEqual(r.get('title'), 'from-args', f'Expected title=from-args to override from-file in:\n{output}')
+
 
 def conf_parsing(self):
     from kitty.config import defaults, load_config