Guard executes shell scripts twice

guard, ruby

Solution

Seems like a bug/feature of `guard` and/or `guard-shell`. I'd report in issue on github for it. In the meantime here's an (ugly) workaround to prevent running files where the `mtime` is the same as last time:

# Guardfile
class GFilter
  def self.run(files, &block)
    @mtimes ||= Hash.new

    files.each { |f|
      mtime = File.mtime(f)
      next if @mtimes[f] == mtime
      @mtimes[f] = mtime

      yield f
    }
  end
end

guard 'shell' do
  watch(/^test\.txt$/) {|m| GFilter.run(m) { |f| puts "File: #{f}" } }
end

Problem

I setup an example project with the following structure: ``` Gemfile Guardfile ``` The contents of these files are: ``` # Gemfile source :rubygems gem "guard" gem "guard-shell" ``` and ``` # Guardfile guard 'shell' do watch(/^test\.txt$/) {|m| `echo #{m.inspect} #{File.mtime(m[0])}` } end ``` I then continue to run `guard`. Whenever I echo something into that file, guard registers a change twice. In one shell: ``` $ echo blah >> test.txt ``` In the shell running guard: ``` > [test.txt] 2012-06-26 00:40:22 +0200 > [test.txt] 2012-06-26 00:40:22 +0200 ``` The same behaviour accounts for vim/nano etc. Interestingly, when I just run `echo blah > test.txt`, guard only fires once. Any idea how I can prevent this from happening or whether this is expected behaviour? EDIT: Opened up an issue on github: https://github.com/guard/guard/issues/297#issuecomment-6586266

Original source