From: Derrick Stolee <stolee@gmail.com>
Date: Mon, 26 Apr 2021 16:12:46 GMT
Subject: Re: [PATCH 09/23] fsmonitor--daemon: implement daemon command options
Message-ID: <3aa3c802-0ad1-0a65-d646-0cd574cb8036@gmail.com>
In-Reply-To: <91a0fc4b-505a-fa2b-c797-5e420e836642@gmail.com>

On 4/26/2021 11:47 AM, Derrick Stolee wrote:
> On 4/1/21 11:40 AM, Jeff Hostetler via GitGitGadget wrote:
>> From: Jeff Hostetler <jeffhost@microsoft.com>
> ...
>> +	/* Prepare to (recursively) watch the <worktree-root> directory. */
>> +	strbuf_init(&state.path_worktree_watch, 0);
>> +	strbuf_addstr(&state.path_worktree_watch, absolute_path(get_git_work_tree()));
>> +	state.nr_paths_watching = 1;
> 
> Yes, let's watch the working directory.
> 
>> +	/*
>> +	 * If ".git" is not a directory, then <gitdir> is not inside the
>> +	 * cone of <worktree-root>, so set up a second watch for it.
>> +	 */
>> +	strbuf_init(&state.path_gitdir_watch, 0);
>> +	strbuf_addbuf(&state.path_gitdir_watch, &state.path_worktree_watch);
>> +	strbuf_addstr(&state.path_gitdir_watch, "/.git");
>> +	if (!is_directory(state.path_gitdir_watch.buf)) {
>> +		strbuf_reset(&state.path_gitdir_watch);
>> +		strbuf_addstr(&state.path_gitdir_watch, absolute_path(get_git_dir()));
>> +		state.nr_paths_watching = 2;
>> +	}
> 
> But why watch the .git directory, especially for a worktree (or
> submodule I guess)? What benefit do we get from events within the
> .git directory? I'm expecting any event within the .git directory
> should be silently ignored.

I see in a following patch that we place a cookie file within the
.git directory. I'm reminded that this is done for a reason: other
filesystem watchers can get into a loop if we place the cookie
file outside of the .git directory. The classic example is VS Code
running 'git status' in a loop because Watchman writes a cookie
into the root of the working directory.

Thanks,
-Stolee