ENOENT on emacs interlock files. about sane

[amasad]

Do you have concrete steps to repro on a OSX? (almost never used emacs)

[SohumB]

On my debian system on ext4, simply running ln -s nonexistent file in a directory sane is watching triggers the bug, given that there is no file called nonexistent in that directory, of course.

[amasad]

Doesn't repro in OSX. Don't have a debian handy at the moment.
cc @wez is this a watcman KP?

[SohumB]

That's weird. stating a symlink to a nonexistent file doesn't error on osx? I wasn't expecting there to be an OS difference here; that seems like the only sensible answer for the filesystem to provide....

I can tell you this patch fixes the bug, but I don't know what any further consequences are of doing it:

diff --git a/src/watchman_watcher.js b/src/watchman_watcher.js
index 14e3d61..e8d61a1 100644
--- a/src/watchman_watcher.js
+++ b/src/watchman_watcher.js
@@ -124,7 +124,8 @@ WatchmanWatcher.prototype.handleFileChange = function(changeDescriptor) {
     self.emitEvent(DELETE_EVENT, changeDescriptor.name, self.root);
   } else {
     fs.stat(absPath, function(error, stat) {
-      if (handleError(self, error)) {
+      if (error) {
+        self.emitEvent(DELETE_EVENT, changeDescriptor.name, self.root);
         return;
       }

[amasad]

This diff makes me think it's a watchman bug. It means that watchman is not setting the exists flag to false for this file.
Can you please try reproducing with watchman? I'm happy to work around it but we need to report it.

[SohumB]

I guess technically the symlink does exist, is why? At least in the manual ln -s nonexistent file case; now I'm wondering if this is somehow a different case from emacs deleting its interlock files...

I'll try repro-ing once I figure out how to use watchman directly :p

[wez]

Watchman doesn't care what the symlink points to. It will report .#menus-test.js as existing because it exists in the filesystem even if the target of the symlink doesn't exist. I think you should switch to fs.lstat instead of fs.stat so that you don't try to follow symlinks.