`brew search' command

Example usage:
  brew search w  # formulae containing w
  brew search ^w # formulae starting with w

No parameters lists all packages.

Also adds puts_columns to util, and uses it for output.

Signed Off By: Max Howell <max@methylblue.com>

I changed the command from 'available' to search because this is more similar
to how other tools call this function.

The short form is -S, which is the "pacman" tool equivalent.

Library/Homebrew/ARGV+yeast.rb

@@ -88,6 +88,7 @@ Commands:
   list formula ...
   link formula ...
   home formula ...
+  available [formula or regex]
   info [formula] [--github]
   make url
   prune

Library/Homebrew/utils.rb

@@ -74,3 +74,9 @@ end
 def curl url, *args
   safe_system 'curl', '-f#LA', HOMEBREW_USER_AGENT, url, *args
 end
+
+def puts_columns items, cols = 4
+  items = items.join("\n") if items.is_a?(Array)
+  width=`stty size`.chomp.split(" ").last
+  IO.popen("pr -#{cols} -t", "w"){|io| io.write(items) }
+end

bin/brew

@@ -60,6 +60,10 @@ begin
         exec "find", *ARGV.kegs+%w[-not -type d -print]
       end
 
+    when 'search', '-S'
+      formulae = (HOMEBREW_PREFIX+'Library'+'Formula').children.sort.map{|f| f.basename('.rb') }
+      puts_columns formulae.grep(Regexp.new(ARGV.first || ''))
+
     when 'edit'
       if ARGV.named_empty?
         exec "mate", *Dir["#{HOMEBREW_PREFIX}/Library/*"]<<
@@ -71,12 +75,7 @@ begin
 
     when 'install'
       if ARGV.named_empty?
-        # TODO I tried to columnise it using the 'column' utility but it uses
-        # tabs rather than spaces and the output looked wrong
-        puts "You must specify a formula. The following are available:" unless ARGV.quieter?
-        (HOMEBREW_PREFIX+'Library'+'Formula').children.sort.each do |f|
-          puts f.basename('.rb')
-        end
+        puts "You must specify a formula. Search for available formulae with `brew search'."
         exit 0
       end