deprecate colon-less syntax, add check command

lib/foreman/cli.rb

@@ -48,6 +48,14 @@ class Foreman::CLI < Thor
     error ex.message
   end
 
+  desc "check", "Validate your application's Procfile"
+
+  def check
+    processes = engine.processes_in_order.map { |p| p.first }
+    error "no processes defined" unless processes.length > 0
+    display "valid procfile detected (#{processes.join(', ')})"
+  end
+
 private ######################################################################
 
   def check_procfile!
@@ -64,6 +72,10 @@ private ######################################################################
 
 private ######################################################################
 
+  def display(message)
+    puts message
+  end
+
   def error(message)
     puts "ERROR: #{message}"
     exit 1

lib/foreman/engine.rb

@@ -25,7 +25,11 @@ class Foreman::Engine
       @order = []
       procfile.split("\n").inject({}) do |hash, line|
         next if line.strip == ""
-        name, command = line.split(/:? +/, 2)
+        name, command = line.split(/ *: +/, 2)
+        unless command
+          warn_deprecated_procfile!
+          name, command = line.split(/ +/, 2)
+        end
         process = Foreman::Process.new(name, command)
         process.color = next_color
         @order << process.name
@@ -178,4 +182,12 @@ private ######################################################################
     @current_color >= COLORS.length ? "" : COLORS[@current_color]
   end
 
+  def warn_deprecated_procfile!
+    return if @already_warned_deprecated
+    @already_warned_deprecated = true
+    puts "!!! This format of Procfile is deprecated, and will not work starting in v0.12"
+    puts "!!! Use a colon to separate the process name from the command"
+    puts "!!! e.g.   web: thin start"
+  end
+
 end