entr enhancements [feature suggestions]

[essenciary]

Here are a few suggested features which would make entr more powerful:

1 - pass the matched file as an argument to the callback function.
Something in the line of:

entr([...]) do file 
...
end

This would allow for more granular logic.

2 - allow passing folders, not just files. There's rarely a need to watch individual files, it's more like "all the files in this folder" (ideally recursively).

3 - it really shouldn't be blocking, but I assume that can be easily addressed with @spawn, @fetch, etc.

---

My use case would be something like this:

if config.AUTO_RELOAD 
  @spawn entr(
    filter(Revise.watched_files) do file_path
      startswith(file_path, Genie.APP_PATH)
    end
  ) do  
    websockets.reload_page()
  end
end

---

If you think they'd be useful I can make a PR.

[timholy]

Yes, please make a PR. Note #308.

[essenciary]

@timholy Thanks, will do!

[tkluck]

As for (3) you might be interested in #443 .

[c42f]

With #488 is merged, most of this is addressed.

(1) is mostly addressed because functions f passed to add_callback(f, [files]) are only triggered for the specific files listed.
(3) is fixed directly because add_callback isn't blocking.

(2) is not yet addressed, I think.

[ffevotte]

I think (2) should be addressed as well, especially thanks to

Revise.jl/src/pkgs.jl

Lines 313 to 317 in 397db6d

	if isdir(fullpath)
	# Detected a modification in a directory that we're watching in
	# itself (not as a container for watched files)
	push!(latestfiles, file=>id)
	continue

Example:

julia> mkdir("foo")
"foo"

julia> using Revise

julia> t = @async Revise.entr(["foo"], postpone=true) do
         println("update")
       end
Task (runnable) @0x00007feed259b820

# Watching a directory translates to watching file "" within directory itself ("/tmp/foo")
julia> Revise.watched_files
Dict{String,Revise.WatchList} with 1 entry:
  "/tmp/foo" => WatchList(1.60578e9, Dict{String,Base.PkgId}(""=> [top-level]))

# File creation
julia> touch("foo/bar"); sleep(1)
update

# File creation, again
julia> touch("foo/baz"); sleep(1)
update

# File modification
julia> touch("foo/bar"); sleep(1)
update

# File deletion
julia> rm("foo/baz"); sleep(1)
update

(I seem to recall that watching directories can behave differently on some systems...)

[timholy]

Let's close this. Thanks for all who have contributed to entr!