handle fully-qualified cask names, fixes #2235

[rolandwalker]

form <user>/<repo>/<cask> may be used on cmdline, matching homebrew

• refactor Cask::Source::Tap into Cask::Source::Tapped, removing
  code, only handling unqualified cask names here now (ie no slash)
• create Cask::Source::TappedQualified, handling <user>-<repo>/<cask>
  form as before, and new form <user>/<repo>/<cask>, for the case that
  the relevant tap already exists
• create Cask::Source::UntappedQualified, handling both command-line
  forms as above, but implicitly creating adding a new tap if it
  does not already exist
• add module Cask::QualifiedCaskName for utility functions on qualified
  Cask names

[rolandwalker]

Note, there is an alternate way to handle <user>/<repo>/<cask> when the tap does not already exist, which is to expand the Cask name to a URI (not to implicitly add the tap). Homebrew implicitly adds the tap, as described by @sonots in #2235, so I followed that logic. However, the expand-to-URI approach also has some merits, so I'm inlining a patch for that below for reference. For brevity, the diff is against the current PR, not master.

Sat Jan 4 07:31:24 2014 -0500 51b2ee5 (HEAD, qualified_cask_names_as_uris) alternate implementation of FQ cask names  [Roland Walker]
diff --git a/lib/cask/qualified_cask_name.rb b/lib/cask/qualified_cask_name.rb
index cb554a5..5b29511 100644
--- a/lib/cask/qualified_cask_name.rb
+++ b/lib/cask/qualified_cask_name.rb
@@ -46,4 +46,13 @@ module Cask::QualifiedCaskName
     repo.sub!(%r{^#{repo_prefix}}, '')
     [user, repo, cask]
   end
+
+  def self.github_raw_url
+    'https://raw.github.com'
+  end
+
+  def self.to_uri(name)
+    user, repo, cask = self.parse(name)
+    "#{github_raw_url}/#{user}/#{repo_prefix}#{repo}/master/Casks/#{cask}.rb"
+  end
 end
diff --git a/lib/cask/source/untapped_qualified.rb b/lib/cask/source/untapped_qualified.rb
index edf22ff..33df678 100644
--- a/lib/cask/source/untapped_qualified.rb
+++ b/lib/cask/source/untapped_qualified.rb
@@ -1,14 +1,11 @@
-require 'cask/source/tapped_qualified'
-require 'cmd/tap'
+require 'cask/source/uri'

-class Cask::Source::UntappedQualified < Cask::Source::TappedQualified
-  def self.path_for_query(query)
-    user, repo, cask = Cask::QualifiedCaskName::parse(query)
-    tap = "#{user}-#{repo}"
-    unless Cask.tapspath.join(tap).exist?
-      ohai "Adding new tap '#{tap}'"
-      Homebrew.install_tap(user, repo)
-    end
-    Cask.tapspath.join(tap, 'Casks', "#{cask}.rb")
+class Cask::Source::UntappedQualified < Cask::Source::URI
+  def self.me?(query)
+    !!Cask::QualifiedCaskName::parse(query)
+  end
+
+  def initialize(query)
+    @uri = Cask::QualifiedCaskName::to_uri(query)
   end
 end

[phinze]

Wow this is great work @rolandwalker! 👍

I love that this can auto-tap for you - removing a command for users to install from non-standard taps. Cool stuff. ⛵

[sonots]

Thank you for your great work @rolandwalker 👯