--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/test/test-fs-event.c	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,1220 @@
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+#include "task.h"
+
+#include <string.h>
+#include <fcntl.h>
+
+#if defined(__APPLE__) && !TARGET_OS_IPHONE
+# include <AvailabilityMacros.h>
+#endif
+
+static uv_fs_event_t fs_event;
+static const char file_prefix[] = "fsevent-";
+static const int fs_event_file_count = 16;
+#if (defined(__APPLE__) && !defined(__TSAN__)) || defined(_WIN32)
+static const char file_prefix_in_subdir[] = "subdir";
+static int fs_multievent_cb_called;
+#endif
+static uv_timer_t timer;
+static int timer_cb_called;
+static int close_cb_called;
+static int fs_event_created;
+static int fs_event_removed;
+static int fs_event_cb_called;
+#if defined(PATH_MAX)
+static char fs_event_filename[PATH_MAX];
+#else
+static char fs_event_filename[1024];
+#endif  /* defined(PATH_MAX) */
+static int timer_cb_touch_called;
+static int timer_cb_exact_called;
+
+static void fs_event_fail(uv_fs_event_t* handle,
+                          const char* filename,
+                          int events,
+                          int status) {
+  ASSERT(0 && "should never be called");
+}
+
+static void create_dir(const char* name) {
+  int r;
+  uv_fs_t req;
+  r = uv_fs_mkdir(NULL, &req, name, 0755, NULL);
+  ASSERT(r == 0 || r == UV_EEXIST);
+  uv_fs_req_cleanup(&req);
+}
+
+static void create_file(const char* name) {
+  int r;
+  uv_file file;
+  uv_fs_t req;
+
+  r = uv_fs_open(NULL, &req, name, UV_FS_O_WRONLY | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  file = r;
+  uv_fs_req_cleanup(&req);
+  r = uv_fs_close(NULL, &req, file, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+}
+
+static int delete_dir(const char* name) {
+  int r;
+  uv_fs_t req;
+  r = uv_fs_rmdir(NULL, &req, name, NULL);
+  uv_fs_req_cleanup(&req);
+  return r;
+}
+
+static int delete_file(const char* name) {
+  int r;
+  uv_fs_t req;
+  r = uv_fs_unlink(NULL, &req, name, NULL);
+  uv_fs_req_cleanup(&req);
+  return r;
+}
+
+static void touch_file(const char* name) {
+  int r;
+  uv_file file;
+  uv_fs_t req;
+  uv_buf_t buf;
+
+  r = uv_fs_open(NULL, &req, name, UV_FS_O_RDWR, 0, NULL);
+  ASSERT_GE(r, 0);
+  file = r;
+  uv_fs_req_cleanup(&req);
+
+  buf = uv_buf_init("foo", 4);
+  r = uv_fs_write(NULL, &req, file, &buf, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_close(NULL, &req, file, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+}
+
+static void close_cb(uv_handle_t* handle) {
+  ASSERT_NOT_NULL(handle);
+  close_cb_called++;
+}
+
+static void fail_cb(uv_fs_event_t* handle,
+                    const char* path,
+                    int events,
+                    int status) {
+  ASSERT(0 && "fail_cb called");
+}
+
+static void fs_event_cb_dir(uv_fs_event_t* handle, const char* filename,
+  int events, int status) {
+  ++fs_event_cb_called;
+  ASSERT_PTR_EQ(handle, &fs_event);
+  ASSERT_OK(status);
+  ASSERT_EQ(events, UV_CHANGE);
+  #if defined(__APPLE__) || defined(_WIN32) || defined(__linux__)
+  ASSERT_OK(strcmp(filename, "file1"));
+  #else
+  ASSERT(filename == NULL || strcmp(filename, "file1") == 0);
+  #endif
+  ASSERT_OK(uv_fs_event_stop(handle));
+  uv_close((uv_handle_t*)handle, close_cb);
+}
+
+static void fs_event_cb_del_dir(uv_fs_event_t* handle,
+                                const char* filename,
+                                int events,
+                                int status) {
+  ++fs_event_cb_called;
+  ASSERT_PTR_EQ(handle, &fs_event);
+  ASSERT_OK(status);
+  ASSERT(events == UV_CHANGE || events == UV_RENAME);
+  /* There is a bug in the FreeBSD kernel where the filename is sometimes NULL.
+   * Refs: https://github.com/libuv/libuv/issues/4606
+   */
+  #if defined(__FreeBSD__)
+  ASSERT(filename == NULL || strcmp(filename, "watch_del_dir") == 0);
+  #else
+  ASSERT_OK(strcmp(filename, "watch_del_dir"));
+  #endif
+  ASSERT_OK(uv_fs_event_stop(handle));
+  uv_close((uv_handle_t*)handle, close_cb);
+}
+
+static const char* fs_event_get_filename(int i) {
+  snprintf(fs_event_filename,
+           sizeof(fs_event_filename),
+           "watch_dir/%s%d",
+           file_prefix,
+           i);
+  return fs_event_filename;
+}
+
+static void fs_event_create_files(uv_timer_t* handle) {
+  /* Make sure we're not attempting to create files we do not intend */
+  ASSERT_LT(fs_event_created, fs_event_file_count);
+
+  /* Create the file */
+  create_file(fs_event_get_filename(fs_event_created));
+
+  if (++fs_event_created < fs_event_file_count) {
+    /* Create another file on a different event loop tick.  We do it this way
+     * to avoid fs events coalescing into one fs event. */
+    ASSERT_OK(uv_timer_start(&timer, fs_event_create_files, 100, 0));
+  }
+}
+
+static void fs_event_del_dir(uv_timer_t* handle) {
+  int r;
+
+  r = delete_dir("watch_del_dir");
+  ASSERT_OK(r);
+
+  uv_close((uv_handle_t*)handle, close_cb);
+}
+
+static void fs_event_unlink_files(uv_timer_t* handle) {
+  int r;
+  int i;
+
+  /* NOTE: handle might be NULL if invoked not as timer callback */
+  if (handle == NULL) {
+    /* Unlink all files */
+    for (i = 0; i < 16; i++) {
+      r = delete_file(fs_event_get_filename(i));
+      if (handle != NULL)
+        ASSERT_OK(r);
+    }
+  } else {
+    /* Make sure we're not attempting to remove files we do not intend */
+    ASSERT_LT(fs_event_removed, fs_event_file_count);
+
+    /* Remove the file */
+    ASSERT_OK(delete_file(fs_event_get_filename(fs_event_removed)));
+
+    if (++fs_event_removed < fs_event_file_count) {
+      /* Remove another file on a different event loop tick.  We do it this way
+       * to avoid fs events coalescing into one fs event. */
+      ASSERT_OK(uv_timer_start(&timer, fs_event_unlink_files, 1, 0));
+    }
+  }
+}
+
+static void fs_event_cb_dir_multi_file(uv_fs_event_t* handle,
+                                       const char* filename,
+                                       int events,
+                                       int status) {
+  fs_event_cb_called++;
+  ASSERT_PTR_EQ(handle, &fs_event);
+  ASSERT_OK(status);
+  ASSERT(events == UV_CHANGE || events == UV_RENAME);
+#if defined(__APPLE__) || defined(_WIN32) || defined(__linux__)
+  ASSERT_NOT_NULL(filename);
+  ASSERT_MEM_EQ(filename, file_prefix, sizeof(file_prefix) - 1);
+#else
+  if (filename != NULL)
+    ASSERT_MEM_EQ(filename, file_prefix, sizeof(file_prefix) - 1);
+#endif
+
+  if (fs_event_created + fs_event_removed == fs_event_file_count) {
+    /* Once we've processed all create events, delete all files */
+    ASSERT_OK(uv_timer_start(&timer, fs_event_unlink_files, 1, 0));
+  } else if (fs_event_cb_called == 2 * fs_event_file_count) {
+    /* Once we've processed all create and delete events, stop watching */
+    uv_close((uv_handle_t*) &timer, close_cb);
+    uv_close((uv_handle_t*) handle, close_cb);
+  }
+}
+
+#if (defined(__APPLE__) && !defined(__TSAN__)) || defined(_WIN32)
+static const char* fs_event_get_filename_in_subdir(int i) {
+  snprintf(fs_event_filename,
+           sizeof(fs_event_filename),
+           "watch_dir/subdir/%s%d",
+           file_prefix,
+           i);
+  return fs_event_filename;
+}
+
+static void fs_event_create_files_in_subdir(uv_timer_t* handle) {
+  /* Make sure we're not attempting to create files we do not intend */
+  ASSERT_LT(fs_event_created, fs_event_file_count);
+
+  /* Create the file */
+  create_file(fs_event_get_filename_in_subdir(fs_event_created));
+
+  if (++fs_event_created < fs_event_file_count) {
+    /* Create another file on a different event loop tick.  We do it this way
+     * to avoid fs events coalescing into one fs event. */
+    ASSERT_OK(uv_timer_start(&timer, fs_event_create_files_in_subdir, 100, 0));
+  }
+}
+
+static void fs_event_unlink_files_in_subdir(uv_timer_t* handle) {
+  int r;
+  int i;
+
+  /* NOTE: handle might be NULL if invoked not as timer callback */
+  if (handle == NULL) {
+    /* Unlink all files */
+    for (i = 0; i < 16; i++) {
+      r = delete_file(fs_event_get_filename_in_subdir(i));
+      if (handle != NULL)
+        ASSERT_OK(r);
+    }
+  } else {
+    /* Make sure we're not attempting to remove files we do not intend */
+    ASSERT_LT(fs_event_removed, fs_event_file_count);
+
+    /* Remove the file */
+    ASSERT_OK(delete_file(fs_event_get_filename_in_subdir(fs_event_removed)));
+
+    if (++fs_event_removed < fs_event_file_count) {
+      /* Remove another file on a different event loop tick.  We do it this way
+       * to avoid fs events coalescing into one fs event. */
+      ASSERT_OK(uv_timer_start(&timer,
+                               fs_event_unlink_files_in_subdir,
+                               1,
+                               0));
+    }
+  }
+}
+
+static void fs_event_cb_dir_multi_file_in_subdir(uv_fs_event_t* handle,
+                                                 const char* filename,
+                                                 int events,
+                                                 int status) {
+#ifdef _WIN32
+  /* Each file created (or deleted) will cause this callback to be called twice
+   * under Windows: once with the name of the file, and second time with the
+   * name of the directory. We will ignore the callback for the directory
+   * itself. */
+  if (filename && strcmp(filename, file_prefix_in_subdir) == 0)
+    return;
+#endif
+  /* It may happen that the "subdir" creation event is captured even though
+   * we started watching after its actual creation.
+   */
+  if (strcmp(filename, "subdir") == 0)
+    return;
+
+  fs_multievent_cb_called++;
+  ASSERT_PTR_EQ(handle, &fs_event);
+  ASSERT_OK(status);
+  ASSERT(events == UV_CHANGE || events == UV_RENAME);
+  #if defined(__APPLE__) || defined(_WIN32) || defined(__linux__)
+  ASSERT_OK(strncmp(filename,
+                    file_prefix_in_subdir,
+                    sizeof(file_prefix_in_subdir) - 1));
+  #else
+  ASSERT_NE(filename == NULL ||
+            strncmp(filename,
+                    file_prefix_in_subdir,
+                    sizeof(file_prefix_in_subdir) - 1) == 0, 0);
+  #endif
+
+  if (fs_event_created == fs_event_file_count &&
+      fs_multievent_cb_called == fs_event_created) {
+    /* Once we've processed all create events, delete all files */
+    ASSERT_OK(uv_timer_start(&timer,
+                             fs_event_unlink_files_in_subdir,
+                             1,
+                             0));
+  } else if (fs_multievent_cb_called == 2 * fs_event_file_count) {
+    /* Once we've processed all create and delete events, stop watching */
+    ASSERT_EQ(fs_event_removed, fs_event_file_count);
+    uv_close((uv_handle_t*) &timer, close_cb);
+    uv_close((uv_handle_t*) handle, close_cb);
+  }
+}
+#endif
+
+static void fs_event_cb_file(uv_fs_event_t* handle, const char* filename,
+  int events, int status) {
+  ++fs_event_cb_called;
+  ASSERT_PTR_EQ(handle, &fs_event);
+  ASSERT_OK(status);
+  ASSERT_EQ(events, UV_CHANGE);
+  #if defined(__APPLE__) || defined(_WIN32) || defined(__linux__)
+  ASSERT_OK(strcmp(filename, "file2"));
+  #else
+  ASSERT(filename == NULL || strcmp(filename, "file2") == 0);
+  #endif
+  ASSERT_OK(uv_fs_event_stop(handle));
+  uv_close((uv_handle_t*)handle, close_cb);
+}
+
+static void fs_event_cb_file_current_dir(uv_fs_event_t* handle,
+  const char* filename, int events, int status) {
+  ++fs_event_cb_called;
+
+  ASSERT_PTR_EQ(handle, &fs_event);
+  ASSERT_OK(status);
+  ASSERT_EQ(events, UV_CHANGE);
+  #if defined(__APPLE__) || defined(_WIN32) || defined(__linux__)
+  ASSERT_OK(strcmp(filename, "watch_file"));
+  #else
+  ASSERT(filename == NULL || strcmp(filename, "watch_file") == 0);
+  #endif
+
+  uv_close((uv_handle_t*)handle, close_cb);
+}
+
+static void timer_cb_file(uv_timer_t* handle) {
+  ++timer_cb_called;
+
+  if (timer_cb_called == 1) {
+    touch_file("watch_dir/file1");
+  } else {
+    touch_file("watch_dir/file2");
+    uv_close((uv_handle_t*)handle, close_cb);
+  }
+}
+
+static void timer_cb_touch(uv_timer_t* timer) {
+  uv_close((uv_handle_t*)timer, NULL);
+  touch_file((char*) timer->data);
+  timer_cb_touch_called++;
+}
+
+static void timer_cb_exact(uv_timer_t* handle) {
+  int r;
+
+  if (timer_cb_exact_called == 0) {
+    touch_file("watch_dir/file.js");
+  } else {
+    uv_close((uv_handle_t*)handle, NULL);
+    r = uv_fs_event_stop(&fs_event);
+    ASSERT_OK(r);
+    uv_close((uv_handle_t*) &fs_event, NULL);
+  }
+
+  ++timer_cb_exact_called;
+}
+
+static void timer_cb_watch_twice(uv_timer_t* handle) {
+  uv_fs_event_t* handles = handle->data;
+  uv_close((uv_handle_t*) (handles + 0), NULL);
+  uv_close((uv_handle_t*) (handles + 1), NULL);
+  uv_close((uv_handle_t*) handle, NULL);
+}
+
+static void fs_event_cb_close(uv_fs_event_t* handle,
+                              const char* filename,
+                              int events,
+                              int status) {
+  ASSERT_OK(status);
+
+  ASSERT_LT(fs_event_cb_called, 3);
+  ++fs_event_cb_called;
+
+  if (fs_event_cb_called == 3) {
+    uv_close((uv_handle_t*) handle, close_cb);
+  }
+}
+
+
+TEST_IMPL(fs_event_watch_dir) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#elif defined(__MVS__)
+  RETURN_SKIP("Directory watching not supported on this platform.");
+#elif defined(__APPLE__) && defined(__TSAN__)
+  RETURN_SKIP("Times out under TSAN.");
+#endif
+
+  uv_loop_t* loop = uv_default_loop();
+  int r;
+
+  /* Setup */
+  fs_event_unlink_files(NULL);
+  delete_file("watch_dir/file2");
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+  create_dir("watch_dir");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_cb_dir_multi_file, "watch_dir", 0);
+  ASSERT_OK(r);
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+  r = uv_timer_start(&timer, fs_event_create_files, 100, 0);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(fs_event_cb_called, fs_event_created + fs_event_removed);
+  ASSERT_EQ(2, close_cb_called);
+
+  /* Cleanup */
+  fs_event_unlink_files(NULL);
+  delete_file("watch_dir/file2");
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_watch_delete_dir) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#elif defined(__MVS__)
+  RETURN_SKIP("Directory watching not supported on this platform.");
+#elif defined(__APPLE__) && defined(__TSAN__)
+  RETURN_SKIP("Times out under TSAN.");
+#endif
+
+  uv_loop_t* loop = uv_default_loop();
+  int r;
+
+  /* Setup */
+  fs_event_unlink_files(NULL);
+  delete_dir("watch_del_dir/");
+  create_dir("watch_del_dir");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_cb_del_dir, "watch_del_dir", 0);
+  ASSERT_OK(r);
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+  r = uv_timer_start(&timer, fs_event_del_dir, 100, 0);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, fs_event_cb_called);
+  ASSERT_EQ(2, close_cb_called);
+
+  /* Cleanup */
+  fs_event_unlink_files(NULL);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_event_watch_dir_recursive) {
+#if defined(__APPLE__) && defined(__TSAN__)
+  RETURN_SKIP("Times out under TSAN.");
+#elif defined(__APPLE__) || defined(_WIN32)
+  uv_loop_t* loop;
+  int r;
+  uv_fs_event_t fs_event_root;
+
+  /* Setup */
+  loop = uv_default_loop();
+  fs_event_unlink_files(NULL);
+  delete_file("watch_dir/file2");
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/subdir");
+  delete_dir("watch_dir/");
+  create_dir("watch_dir");
+  create_dir("watch_dir/subdir");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event,
+                        fs_event_cb_dir_multi_file_in_subdir,
+                        "watch_dir",
+                        UV_FS_EVENT_RECURSIVE);
+  ASSERT_OK(r);
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+  r = uv_timer_start(&timer, fs_event_create_files_in_subdir, 100, 0);
+  ASSERT_OK(r);
+
+#ifndef _WIN32
+  /* Also try to watch the root directory.
+   * This will be noisier, so we're just checking for any couple events to happen. */
+  r = uv_fs_event_init(loop, &fs_event_root);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event_root,
+                        fs_event_cb_close,
+                        "/",
+                        UV_FS_EVENT_RECURSIVE);
+  ASSERT_OK(r);
+#else
+  fs_event_cb_called += 3;
+  close_cb_called += 1;
+  (void)fs_event_root;
+#endif
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(fs_multievent_cb_called, fs_event_created + fs_event_removed);
+  ASSERT_EQ(3, fs_event_cb_called);
+  ASSERT_EQ(3, close_cb_called);
+
+  /* Cleanup */
+  fs_event_unlink_files_in_subdir(NULL);
+  delete_file("watch_dir/file2");
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/subdir");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+#else
+  RETURN_SKIP("Recursive directory watching not supported on this platform.");
+#endif
+}
+
+#ifdef _WIN32
+TEST_IMPL(fs_event_watch_dir_short_path) {
+  uv_loop_t* loop;
+  uv_fs_t req;
+  int has_shortnames;
+  int r;
+
+  /* Setup */
+  loop = uv_default_loop();
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+  create_dir("watch_dir");
+  create_file("watch_dir/file1");
+
+  /* Newer version of Windows ship with
+     HKLM\SYSTEM\CurrentControlSet\Control\FileSystem\NtfsDisable8dot3NameCreation
+     not equal to 0. So we verify the files we created are addressable by a 8.3
+     short name */
+  has_shortnames = uv_fs_stat(NULL, &req, "watch_~1", NULL) != UV_ENOENT;
+  if (has_shortnames) {
+    r = uv_fs_event_init(loop, &fs_event);
+    ASSERT_OK(r);
+    r = uv_fs_event_start(&fs_event, fs_event_cb_dir, "watch_~1", 0);
+    ASSERT_OK(r);
+    r = uv_timer_init(loop, &timer);
+    ASSERT_OK(r);
+    r = uv_timer_start(&timer, timer_cb_file, 100, 0);
+    ASSERT_OK(r);
+
+    uv_run(loop, UV_RUN_DEFAULT);
+
+    ASSERT_EQ(1, fs_event_cb_called);
+    ASSERT_EQ(1, timer_cb_called);
+    ASSERT_EQ(1, close_cb_called);
+  }
+
+  /* Cleanup */
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+
+  if (!has_shortnames)
+    RETURN_SKIP("Was not able to address files with 8.3 short name.");
+
+  return 0;
+}
+#endif
+
+
+TEST_IMPL(fs_event_watch_file) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+
+  uv_loop_t* loop = uv_default_loop();
+  int r;
+
+  /* Setup */
+  delete_file("watch_dir/file2");
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+  create_dir("watch_dir");
+  create_file("watch_dir/file1");
+  create_file("watch_dir/file2");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_cb_file, "watch_dir/file2", 0);
+  ASSERT_OK(r);
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+  r = uv_timer_start(&timer, timer_cb_file, 100, 100);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, fs_event_cb_called);
+  ASSERT_EQ(2, timer_cb_called);
+  ASSERT_EQ(2, close_cb_called);
+
+  /* Cleanup */
+  delete_file("watch_dir/file2");
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_watch_file_exact_path) {
+  /*
+    This test watches a file named "file.jsx" and modifies a file named
+    "file.js". The test verifies that no events occur for file.jsx.
+  */
+
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  /* Setup */
+  delete_file("watch_dir/file.js");
+  delete_file("watch_dir/file.jsx");
+  delete_dir("watch_dir/");
+  create_dir("watch_dir");
+  create_file("watch_dir/file.js");
+  create_file("watch_dir/file.jsx");
+#if defined(__APPLE__) && !defined(MAC_OS_X_VERSION_10_12)
+  /* Empirically, FSEvents seems to (reliably) report the preceding
+   * create_file events prior to macOS 10.11.6 in the subsequent fs_watch
+   * creation, but that behavior hasn't been observed to occur on newer
+   * versions. Give a long delay here to let the system settle before running
+   * the test. */
+  uv_sleep(1100);
+  uv_update_time(loop);
+#endif
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_fail, "watch_dir/file.jsx", 0);
+  ASSERT_OK(r);
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+  r = uv_timer_start(&timer, timer_cb_exact, 100, 100);
+  ASSERT_OK(r);
+  r = uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_OK(r);
+  ASSERT_EQ(2, timer_cb_exact_called);
+
+  /* Cleanup */
+  delete_file("watch_dir/file.js");
+  delete_file("watch_dir/file.jsx");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_watch_file_twice) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+  const char path[] = "test/fixtures/empty_file";
+  uv_fs_event_t watchers[2];
+  uv_timer_t timer;
+  uv_loop_t* loop;
+
+  loop = uv_default_loop();
+  timer.data = watchers;
+
+  ASSERT_OK(uv_fs_event_init(loop, watchers + 0));
+  ASSERT_OK(uv_fs_event_start(watchers + 0, fail_cb, path, 0));
+  ASSERT_OK(uv_fs_event_init(loop, watchers + 1));
+  ASSERT_OK(uv_fs_event_start(watchers + 1, fail_cb, path, 0));
+  ASSERT_OK(uv_timer_init(loop, &timer));
+  ASSERT_OK(uv_timer_start(&timer, timer_cb_watch_twice, 10, 0));
+  ASSERT_OK(uv_run(loop, UV_RUN_DEFAULT));
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_watch_file_current_dir) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+  uv_timer_t timer;
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  /* Setup */
+  delete_file("watch_file");
+  create_file("watch_file");
+#if defined(__APPLE__) && !defined(MAC_OS_X_VERSION_10_12)
+  /* Empirically, kevent seems to (sometimes) report the preceding
+   * create_file events prior to macOS 10.11.6 in the subsequent fs_event_start
+   * So let the system settle before running the test. */
+  uv_sleep(1100);
+  uv_update_time(loop);
+#endif
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event,
+                        fs_event_cb_file_current_dir,
+                        "watch_file",
+                        0);
+  ASSERT_OK(r);
+
+
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+
+  timer.data = "watch_file";
+  r = uv_timer_start(&timer, timer_cb_touch, 1100, 0);
+  ASSERT_OK(r);
+
+  ASSERT_OK(timer_cb_touch_called);
+  ASSERT_OK(fs_event_cb_called);
+  ASSERT_OK(close_cb_called);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, timer_cb_touch_called);
+  /* FSEvents on macOS sometimes sends one change event, sometimes two. */
+  ASSERT_NE(0, fs_event_cb_called);
+  ASSERT_EQ(1, close_cb_called);
+
+  /* Cleanup */
+  delete_file("watch_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+#ifdef _WIN32
+TEST_IMPL(fs_event_watch_file_root_dir) {
+  uv_loop_t* loop;
+  int r;
+
+  const char* sys_drive = getenv("SystemDrive");
+  char path[] = "\\\\?\\X:\\bootsect.bak";
+
+  ASSERT_NOT_NULL(sys_drive);
+  strncpy(path + sizeof("\\\\?\\") - 1, sys_drive, 1);
+
+  loop = uv_default_loop();
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fail_cb, path, 0);
+  if (r == UV_ENOENT)
+    RETURN_SKIP("bootsect.bak doesn't exist in system root.\n");
+  ASSERT_OK(r);
+
+  uv_close((uv_handle_t*) &fs_event, NULL);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+#endif
+
+TEST_IMPL(fs_event_no_callback_after_close) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+
+  uv_loop_t* loop = uv_default_loop();
+  int r;
+
+  /* Setup */
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+  create_dir("watch_dir");
+  create_file("watch_dir/file1");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event,
+                        fs_event_cb_file,
+                        "watch_dir/file1",
+                        0);
+  ASSERT_OK(r);
+
+
+  uv_close((uv_handle_t*)&fs_event, close_cb);
+  touch_file("watch_dir/file1");
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_OK(fs_event_cb_called);
+  ASSERT_EQ(1, close_cb_called);
+
+  /* Cleanup */
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_no_callback_on_close) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+
+  uv_loop_t* loop = uv_default_loop();
+  int r;
+
+  /* Setup */
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+  create_dir("watch_dir");
+  create_file("watch_dir/file1");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event,
+                        fs_event_cb_file,
+                        "watch_dir/file1",
+                        0);
+  ASSERT_OK(r);
+
+  uv_close((uv_handle_t*)&fs_event, close_cb);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_OK(fs_event_cb_called);
+  ASSERT_EQ(1, close_cb_called);
+
+  /* Cleanup */
+  delete_file("watch_dir/file1");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+static void timer_cb(uv_timer_t* handle) {
+  int r;
+
+  r = uv_fs_event_init(handle->loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_fail, ".", 0);
+  ASSERT_OK(r);
+
+  uv_close((uv_handle_t*)&fs_event, close_cb);
+  uv_close((uv_handle_t*)handle, close_cb);
+}
+
+
+TEST_IMPL(fs_event_immediate_close) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+  uv_timer_t timer;
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+
+  r = uv_timer_start(&timer, timer_cb, 1, 0);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(2, close_cb_called);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_event_close_with_pending_event) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  create_dir("watch_dir");
+  create_file("watch_dir/file");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_fail, "watch_dir", 0);
+  ASSERT_OK(r);
+
+  /* Generate an fs event. */
+  touch_file("watch_dir/file");
+
+  uv_close((uv_handle_t*)&fs_event, close_cb);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, close_cb_called);
+
+  /* Clean up */
+  delete_file("watch_dir/file");
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_close_with_pending_delete_event) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  create_dir("watch_dir");
+  create_file("watch_dir/file");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_fail, "watch_dir/file", 0);
+  ASSERT_OK(r);
+
+  /* Generate an fs event. */
+  delete_file("watch_dir/file");
+
+  /* Allow time for the remove event to propagate to the pending list. */
+  /* XXX - perhaps just for __sun? */
+  uv_sleep(1100);
+  uv_update_time(loop);
+
+  uv_close((uv_handle_t*)&fs_event, close_cb);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, close_cb_called);
+
+  /* Clean up */
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_close_in_callback) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#elif defined(__MVS__)
+  RETURN_SKIP("Directory watching not supported on this platform.");
+#elif defined(__APPLE__) && defined(__TSAN__)
+  RETURN_SKIP("Times out under TSAN.");
+#endif
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  fs_event_unlink_files(NULL);
+  create_dir("watch_dir");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_cb_close, "watch_dir", 0);
+  ASSERT_OK(r);
+
+  r = uv_timer_init(loop, &timer);
+  ASSERT_OK(r);
+  r = uv_timer_start(&timer, fs_event_create_files, 100, 0);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  uv_close((uv_handle_t*)&timer, close_cb);
+
+  uv_run(loop, UV_RUN_ONCE);
+
+  ASSERT_EQ(2, close_cb_called);
+  ASSERT_EQ(3, fs_event_cb_called);
+
+  /* Clean up */
+  fs_event_unlink_files(NULL);
+  delete_dir("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_start_and_close) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+  uv_loop_t* loop;
+  uv_fs_event_t fs_event1;
+  uv_fs_event_t fs_event2;
+  int r;
+
+  loop = uv_default_loop();
+
+  create_dir("watch_dir");
+
+  r = uv_fs_event_init(loop, &fs_event1);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event1, fs_event_cb_dir, "watch_dir", 0);
+  ASSERT_OK(r);
+
+  r = uv_fs_event_init(loop, &fs_event2);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event2, fs_event_cb_dir, "watch_dir", 0);
+  ASSERT_OK(r);
+
+  uv_close((uv_handle_t*) &fs_event2, close_cb);
+  uv_close((uv_handle_t*) &fs_event1, close_cb);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(2, close_cb_called);
+
+  delete_dir("watch_dir/");
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_getpath) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+  uv_loop_t* loop = uv_default_loop();
+  unsigned i;
+  int r;
+  char buf[1024];
+  size_t len;
+  const char* const watch_dir[] = {
+    "watch_dir",
+    "watch_dir/",
+    "watch_dir///",
+    "watch_dir/subfolder/..",
+    "watch_dir//subfolder//..//",
+  };
+
+  create_dir("watch_dir");
+  create_dir("watch_dir/subfolder");
+
+
+  for (i = 0; i < ARRAY_SIZE(watch_dir); i++) {
+    r = uv_fs_event_init(loop, &fs_event);
+    ASSERT_OK(r);
+    len = sizeof buf;
+    r = uv_fs_event_getpath(&fs_event, buf, &len);
+    ASSERT_EQ(r, UV_EINVAL);
+    r = uv_fs_event_start(&fs_event, fail_cb, watch_dir[i], 0);
+    ASSERT_OK(r);
+    len = 1;
+    r = uv_fs_event_getpath(&fs_event, buf, &len);
+    ASSERT_EQ(r, UV_ENOBUFS);
+    ASSERT_LT(len, sizeof buf); /* sanity check */
+    ASSERT_EQ(len, strlen(watch_dir[i]) + 1);
+    r = uv_fs_event_getpath(&fs_event, buf, &len);
+    ASSERT_OK(r);
+    ASSERT_EQ(len, strlen(watch_dir[i]));
+    ASSERT(strcmp(buf, watch_dir[i]) == 0);
+    r = uv_fs_event_stop(&fs_event);
+    ASSERT_OK(r);
+    uv_close((uv_handle_t*) &fs_event, close_cb);
+
+    uv_run(loop, UV_RUN_DEFAULT);
+
+    ASSERT_EQ(1, close_cb_called);
+    close_cb_called = 0;
+  }
+
+  delete_dir("watch_dir/");
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_event_watch_invalid_path) {
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT_OK(r);
+  r = uv_fs_event_start(&fs_event, fs_event_cb_file, "<:;", 0);
+  ASSERT(r);
+  ASSERT_OK(uv_is_active((uv_handle_t*) &fs_event));
+  r = uv_fs_event_start(&fs_event, fs_event_cb_file, "", 0);
+  ASSERT(r);
+  ASSERT_OK(uv_is_active((uv_handle_t*) &fs_event));
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+static int fs_event_cb_stop_calls;
+
+static void fs_event_cb_stop(uv_fs_event_t* handle, const char* path,
+                             int events, int status) {
+  uv_fs_event_stop(handle);
+  fs_event_cb_stop_calls++;
+}
+
+TEST_IMPL(fs_event_stop_in_cb) {
+  uv_fs_event_t fs;
+  uv_timer_t timer;
+  char path[] = "fs_event_stop_in_cb.txt";
+
+#if defined(NO_FS_EVENTS)
+  RETURN_SKIP(NO_FS_EVENTS);
+#endif
+
+  delete_file(path);
+  create_file(path);
+
+  ASSERT_OK(uv_fs_event_init(uv_default_loop(), &fs));
+  ASSERT_OK(uv_fs_event_start(&fs, fs_event_cb_stop, path, 0));
+
+  /* Note: timer_cb_touch() closes the handle. */
+  timer.data = path;
+  ASSERT_OK(uv_timer_init(uv_default_loop(), &timer));
+  ASSERT_OK(uv_timer_start(&timer, timer_cb_touch, 100, 0));
+
+  ASSERT_OK(fs_event_cb_stop_calls);
+  ASSERT_OK(timer_cb_touch_called);
+
+  ASSERT_OK(uv_run(uv_default_loop(), UV_RUN_DEFAULT));
+
+  ASSERT_EQ(1, fs_event_cb_stop_calls);
+  ASSERT_EQ(1, timer_cb_touch_called);
+
+  uv_close((uv_handle_t*) &fs, NULL);
+  ASSERT_OK(uv_run(uv_default_loop(), UV_RUN_DEFAULT));
+  ASSERT_EQ(1, fs_event_cb_stop_calls);
+
+  delete_file(path);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}