Stat::Callback has 2 arguments for callback: current stat info and previous stat info

http://groups.google.com/group/nodejs/msg/f8e51a8e0c74bd85

doc/api.txt

@@ -137,6 +137,18 @@ The second argument is optional. The +options+ if provided should be an
 object containing two members a boolean, +persistent+, and +interval+, a
 polling value in milliseconds. The default is +{persistent: true, interval:
 0}+.
++
+The +listener+ gets two arguments the current stat object and the previous
+stat object:
++
+-------------------------
+process.watchFile(f, function (curr, prev) {
+  sys.puts("the current mtime is: " + curr.mtime);
+  sys.puts("the previous mtime was: " + prev.mtime);
+});
+-------------------------
++
+These stat objects are instances of +posix.Stat+. 
 
 +process.unwatchFile(filename)+::
 Stop watching for changes on +filename+.

lib/posix.js

@@ -1,35 +1,37 @@
-process.fs.Stats.prototype._checkModeProperty = function (property) {
+process.Stats.prototype._checkModeProperty = function (property) {
   return ((this.mode & property) === property);
 };
 
-process.fs.Stats.prototype.isDirectory = function () {
+process.Stats.prototype.isDirectory = function () {
   return this._checkModeProperty(process.S_IFDIR);
 };
 
-process.fs.Stats.prototype.isFile = function () {
+process.Stats.prototype.isFile = function () {
   return this._checkModeProperty(process.S_IFREG);
 };
 
-process.fs.Stats.prototype.isBlockDevice = function () {
+process.Stats.prototype.isBlockDevice = function () {
   return this._checkModeProperty(process.S_IFBLK);
 };
 
-process.fs.Stats.prototype.isCharacterDevice = function () {
+process.Stats.prototype.isCharacterDevice = function () {
   return this._checkModeProperty(process.S_IFCHR);
 };
 
-process.fs.Stats.prototype.isSymbolicLink = function () {
+process.Stats.prototype.isSymbolicLink = function () {
   return this._checkModeProperty(process.S_IFLNK);
 };
 
-process.fs.Stats.prototype.isFIFO = function () {
+process.Stats.prototype.isFIFO = function () {
   return this._checkModeProperty(process.S_IFIFO);
 };
 
-process.fs.Stats.prototype.isSocket = function () {
+process.Stats.prototype.isSocket = function () {
   return this._checkModeProperty(process.S_IFSOCK);
 };
 
+exports.Stats = process.Stats;
+
 for (var key in process.fs) {
   if (process.fs.hasOwnProperty(key)) exports[key] = process.fs[key];
 }

src/node.cc

@@ -160,6 +160,71 @@ ssize_t DecodeWrite(char *buf, size_t buflen,
   return buflen;
 }
 
+#define DEV_SYMBOL         String::NewSymbol("dev")
+#define INO_SYMBOL         String::NewSymbol("ino")
+#define MODE_SYMBOL        String::NewSymbol("mode")
+#define NLINK_SYMBOL       String::NewSymbol("nlink")
+#define UID_SYMBOL         String::NewSymbol("uid")
+#define GID_SYMBOL         String::NewSymbol("gid")
+#define RDEV_SYMBOL        String::NewSymbol("rdev")
+#define SIZE_SYMBOL        String::NewSymbol("size")
+#define BLKSIZE_SYMBOL     String::NewSymbol("blksize")
+#define BLOCKS_SYMBOL      String::NewSymbol("blocks")
+#define ATIME_SYMBOL       String::NewSymbol("atime")
+#define MTIME_SYMBOL       String::NewSymbol("mtime")
+#define CTIME_SYMBOL       String::NewSymbol("ctime")
+
+static Persistent<FunctionTemplate> stats_constructor_template;
+
+Local<Object> BuildStatsObject(struct stat * s) {
+  HandleScope scope;
+
+  Local<Object> stats =
+    stats_constructor_template->GetFunction()->NewInstance();
+
+  /* ID of device containing file */
+  stats->Set(DEV_SYMBOL, Integer::New(s->st_dev));
+
+  /* inode number */
+  stats->Set(INO_SYMBOL, Integer::New(s->st_ino));
+
+  /* protection */
+  stats->Set(MODE_SYMBOL, Integer::New(s->st_mode));
+
+  /* number of hard links */
+  stats->Set(NLINK_SYMBOL, Integer::New(s->st_nlink));
+
+  /* user ID of owner */
+  stats->Set(UID_SYMBOL, Integer::New(s->st_uid));
+
+  /* group ID of owner */
+  stats->Set(GID_SYMBOL, Integer::New(s->st_gid));
+
+  /* device ID (if special file) */
+  stats->Set(RDEV_SYMBOL, Integer::New(s->st_rdev));
+
+  /* total size, in bytes */
+  stats->Set(SIZE_SYMBOL, Integer::New(s->st_size));
+
+  /* blocksize for filesystem I/O */
+  stats->Set(BLKSIZE_SYMBOL, Integer::New(s->st_blksize));
+
+  /* number of blocks allocated */
+  stats->Set(BLOCKS_SYMBOL, Integer::New(s->st_blocks));
+
+  /* time of last access */
+  stats->Set(ATIME_SYMBOL, NODE_UNIXTIME_V8(s->st_atime));
+
+  /* time of last modification */
+  stats->Set(MTIME_SYMBOL, NODE_UNIXTIME_V8(s->st_mtime));
+
+  /* time of last status change */
+  stats->Set(CTIME_SYMBOL, NODE_UNIXTIME_V8(s->st_ctime));
+
+  return scope.Close(stats);
+}
+
+
 // Extracts a C str from a V8 Utf8Value.
 const char* ToCString(const v8::String::Utf8Value& value) {
   return *value ? *value : "<str conversion failed>";
@@ -726,6 +791,13 @@ static Local<Object> Load(int argc, char *argv[]) {
   process->Set(String::NewSymbol("EventEmitter"),
                EventEmitter::constructor_template->GetFunction());
 
+  // Initialize the stats object
+  Local<FunctionTemplate> stat_templ = FunctionTemplate::New();
+  stats_constructor_template = Persistent<FunctionTemplate>::New(stat_templ);
+  process->Set(String::NewSymbol("Stats"),
+      stats_constructor_template->GetFunction());
+
+
   // Initialize the C++ modules..................filename of module
   Promise::Initialize(process);                // events.cc
   Stdio::Initialize(process);                  // stdio.cc

src/node.h

@@ -6,6 +6,8 @@
 #include <eio.h>
 #include <v8.h>
 #include <evcom.h>
+#include <sys/types.h> /* struct stat */
+#include <sys/stat.h>
 
 #include <node_object_wrap.h>
 
@@ -51,6 +53,8 @@ ssize_t DecodeWrite(char *buf,
                     v8::Handle<v8::Value>,
                     enum encoding encoding = BINARY);
 
+v8::Local<v8::Object> BuildStatsObject(struct stat * s);
+
 
 }  // namespace node
 #endif  // SRC_NODE_H_

src/node_file.cc

@@ -13,20 +13,7 @@ namespace node {
 
 using namespace v8;
 
-#define DEV_SYMBOL         String::NewSymbol("dev")
+#define BAD_ARGUMENTS Exception::TypeError(String::New("Bad argument"))
-#define INO_SYMBOL         String::NewSymbol("ino")
-#define MODE_SYMBOL        String::NewSymbol("mode")
-#define NLINK_SYMBOL       String::NewSymbol("nlink")
-#define UID_SYMBOL         String::NewSymbol("uid")
-#define GID_SYMBOL         String::NewSymbol("gid")
-#define RDEV_SYMBOL        String::NewSymbol("rdev")
-#define SIZE_SYMBOL        String::NewSymbol("size")
-#define BLKSIZE_SYMBOL     String::NewSymbol("blksize")
-#define BLOCKS_SYMBOL      String::NewSymbol("blocks")
-#define ATIME_SYMBOL       String::NewSymbol("atime")
-#define MTIME_SYMBOL       String::NewSymbol("mtime")
-#define CTIME_SYMBOL       String::NewSymbol("ctime")
-#define BAD_ARGUMENTS      Exception::TypeError(String::New("Bad argument"))
 
 void EIOPromise::Attach(void) {
   ev_ref(EV_DEFAULT_UC);
@@ -58,55 +45,6 @@ EIOPromise* EIOPromise::Create() {
   return ObjectWrap::Unwrap<EIOPromise>(handle);
 }
 
-static Persistent<FunctionTemplate> stats_constructor_template;
-
-static Local<Object> BuildStatsObject(struct stat * s) {
-  HandleScope scope;
-
-  Local<Object> stats =
-    stats_constructor_template->GetFunction()->NewInstance();
-
-  /* ID of device containing file */
-  stats->Set(DEV_SYMBOL, Integer::New(s->st_dev));
-
-  /* inode number */
-  stats->Set(INO_SYMBOL, Integer::New(s->st_ino));
-
-  /* protection */
-  stats->Set(MODE_SYMBOL, Integer::New(s->st_mode));
-
-  /* number of hard links */
-  stats->Set(NLINK_SYMBOL, Integer::New(s->st_nlink));
-
-  /* user ID of owner */
-  stats->Set(UID_SYMBOL, Integer::New(s->st_uid));
-
-  /* group ID of owner */
-  stats->Set(GID_SYMBOL, Integer::New(s->st_gid));
-
-  /* device ID (if special file) */
-  stats->Set(RDEV_SYMBOL, Integer::New(s->st_rdev));
-
-  /* total size, in bytes */
-  stats->Set(SIZE_SYMBOL, Integer::New(s->st_size));
-
-  /* blocksize for filesystem I/O */
-  stats->Set(BLKSIZE_SYMBOL, Integer::New(s->st_blksize));
-
-  /* number of blocks allocated */
-  stats->Set(BLOCKS_SYMBOL, Integer::New(s->st_blocks));
-
-  /* time of last access */
-  stats->Set(ATIME_SYMBOL, NODE_UNIXTIME_V8(s->st_atime));
-
-  /* time of last modification */
-  stats->Set(MTIME_SYMBOL, NODE_UNIXTIME_V8(s->st_mtime));
-
-  /* time of last status change */
-  stats->Set(CTIME_SYMBOL, NODE_UNIXTIME_V8(s->st_ctime));
-
-  return scope.Close(stats);
-}
 
 int EIOPromise::After(eio_req *req) {
   HandleScope scope;
@@ -388,11 +326,6 @@ void File::Initialize(Handle<Object> target) {
   NODE_SET_METHOD(target, "unlink", Unlink);
   NODE_SET_METHOD(target, "write", Write);
 
-  Local<FunctionTemplate> t = FunctionTemplate::New();
-  stats_constructor_template = Persistent<FunctionTemplate>::New(t);
-  target->Set(String::NewSymbol("Stats"),
-      stats_constructor_template->GetFunction());
-
 
   Local<FunctionTemplate> t2 = FunctionTemplate::New(EIOPromise::New);
   EIOPromise::constructor_template = Persistent<FunctionTemplate>::New(t2);

src/node_stat.cc

@@ -32,7 +32,10 @@ void Stat::Callback(EV_P_ ev_stat *watcher, int revents) {
   Stat *handler = static_cast<Stat*>(watcher->data);
   assert(watcher == &handler->watcher_);
   HandleScope scope;
-  handler->Emit("change", 0, NULL);
+  Handle<Value> argv[2];
+  argv[0] = Handle<Value>(BuildStatsObject(&watcher->attr));
+  argv[1] = Handle<Value>(BuildStatsObject(&watcher->prev));
+  handler->Emit("change", 2, argv);
 }
 
 

test/mjsunit/test-stat-handler.js

@@ -8,9 +8,10 @@ var f2 = path.join(fixturesDir, "x2.txt");
 puts("watching for changes of " + f);
 
 var changes = 0;
-process.watchFile(f, function () {
+process.watchFile(f, function (curr, prev) {
   puts(f + " change");
   changes++;
+  assertTrue(curr.mtime != prev.mtime);
   process.unwatchFile(f);
 });