lib/spielbash/view/cli.rb in spielbash-0.1.1 vs lib/spielbash/view/cli.rb in spielbash-0.1.2

@@ -8,11 +8,30 @@
     program_desc 'Tool to automate bash movie-making with asciinema. Be the Spielberg of bash'
 
     desc 'Be verbose'
     switch [:v, :verbose]
 
-    # pre do |global_options, command, options, args|
-    # end
+    # Cross-platform way of finding an executable in the $PATH.
+    #
+    #   which('ruby') #=> /usr/bin/ruby
+    def which(cmd)
+      exts = ENV['PATHEXT'] ? ENV['PATHEXT'].split(';') : ['']
+      ENV['PATH'].split(File::PATH_SEPARATOR).each do |path|
+        exts.each {|ext|
+          exe = File.join(path, "#{cmd}#{ext}")
+          return true if File.executable?(exe) && !File.directory?(exe)
+        }
+      end
+      false
+    end
+
+    pre do |global_options, command, options, args|
+      help_now!('pgrep is not installed!') unless which('pgrep')
+      help_now!('docker is not installed!') unless which('docker')
+      help_now!('tmux is not installed!') unless which('tmux')
+      help_now!('resize is not installed!') unless which('resize')
+      help_now!('asciinema is not installed!') unless which('asciinema')
+    end
 
     desc 'Create a recording'
     command :record do |c|
       c.desc 'Script file path'
       c.flag [:script]
\ No newline at end of file