feat: add ignore-times incremental option

tests/integration/test_features.py

@@ -213,6 +213,26 @@ class TestIncremental:
         with open(received_file, "rb") as f:
             assert f.read() == b"hello world\n"
 
+    def test_ignore_times_transfers_same_size_and_mtime(self, shared_server):
+        clean_dir(DEST_DIR)
+        result, _ = run_client(SOURCE_DIR, DEST_DIR, flags=["-M"], port=shared_server.port)
+        assert result.returncode == 0
+
+        received = get_dest_received_dir(DEST_DIR, SOURCE_DIR)
+        source_file = os.path.join(SOURCE_DIR, "small.txt")
+        received_file = os.path.join(received, "small.txt")
+        source_stat = os.stat(source_file)
+        with open(received_file, "wb") as f:
+            f.write(b"stale data\n")
+        os.utime(received_file, (source_stat.st_atime, source_stat.st_mtime))
+
+        result, _ = run_client(SOURCE_DIR, DEST_DIR,
+                               flags=["-M", "--incremental", "--ignore-times"],
+                               port=shared_server.port)
+        assert result.returncode == 0, f"Ignore-times sync failed: {result.stderr[:200]}"
+        with open(received_file, "rb") as f:
+            assert f.read() == b"hello world\n"
+
 
 class TestDelete:
     def test_delete_removes_extra_files(self, shared_server):

tests/test_client_cli.c

@@ -339,6 +339,24 @@ static void test_parse_args_archive() {
   config_delete(cfg);
 }
 
+static void test_parse_args_ignore_times() {
+  Config* cfg = config_create();
+  char* argv[] = {"fastsync", "-I", "/src", "/dst"};
+  int positional_args[2];
+  int positional_count = 0;
+
+  EXPECT_EQ_INT(parse_args(cfg, 4, argv, positional_args, &positional_count), 0);
+  EXPECT_TRUE(cfg->ignore_times);
+  config_delete(cfg);
+
+  cfg = config_create();
+  char* long_argv[] = {"fastsync", "--ignore-times", "/src", "/dst"};
+  positional_count = 0;
+  EXPECT_EQ_INT(parse_args(cfg, 4, long_argv, positional_args, &positional_count), 0);
+  EXPECT_TRUE(cfg->ignore_times);
+  config_delete(cfg);
+}
+
 void test_client_cli() {
   test_validate_config_required_paths();
   test_validate_config_incompatible_options();
@@ -360,4 +378,5 @@ void test_client_cli() {
   test_parse_args_unknown_option();
   test_parse_args_rejects_unimplemented_options();
   test_parse_args_archive();
+  test_parse_args_ignore_times();
 }

tests/test_config.c

@@ -124,6 +124,7 @@ static void test_config_send_receive() {
   send_cfg->use_chunk_serialization = true;
   send_cfg->use_compression = true;
   send_cfg->use_metadata = true;
+  send_cfg->ignore_times = true;
   send_cfg->compression_level = 5;
   send_cfg->chunk_size = 1024;
 
@@ -156,6 +157,8 @@ static void test_config_send_receive() {
         ok = false;
       if (!recv_cfg->use_chunk_serialization)
         ok = false;
+      if (!recv_cfg->ignore_times)
+        ok = false;
       if (recv_cfg->compression_level != 5)
         ok = false;
       if (recv_cfg->chunk_size != 1024)