Improve Podfile.lock version when the `:head` option is used.

lib/cocoapods/lockfile.rb

@@ -99,17 +99,17 @@ module Pod
     #   @example Strings examples
     #       "libPusher"
     #       "libPusher (1.0)"
-    #       "libPusher (HEAD from 1.0)"
+    #       "libPusher (HEAD based on 1.0)"
     #       "RestKit/JSON"
     #
     # @return [String, Version] The name and the version of a
     # pod.
     #
     def name_and_version_for_pod(string)
-        match_data = string.match(/(\S*) \((.*)\)/)
-        name = match_data[1]
-        vers = Version.from_s(match_data[2])
-        return [name, vers]
+      match_data = string.match(/(\S*) \((.*)\)/)
+      name = match_data[1]
+      vers = Version.from_string(match_data[2])
+      [name, vers]
     end
 
     # @param [String] The string that describes a {Dependency} generated
@@ -241,7 +241,7 @@ module Pod
         end
       end
       pod_and_deps = tmp.sort_by(&:first).map do |name, deps|
-        deps.empty? ? name : {name => deps}
+        deps.empty? ? name : { name => deps }
       end
       hash["PODS"] = pod_and_deps
 
@@ -253,7 +253,7 @@ module Pod
       hash["EXTERNAL SOURCES"] = external_sources unless external_sources.empty?
 
       checksums = {}
-      specs.select {|spec| !spec.defined_in_file.nil? }.each do |spec|
+      specs.select { |spec| !spec.defined_in_file.nil? }.each do |spec|
         checksum = Digest::SHA1.hexdigest(File.read(spec.defined_in_file))
         checksum = checksum.encode('UTF-8') if checksum.respond_to?(:encode)
         checksums[spec.name] = checksum

lib/cocoapods/version.rb

@@ -3,19 +3,23 @@ module Pod
 
     # @returns A Version described by its #to_s method.
     #
-    def self.from_s(string)
-      match = string.match(/HEAD from (.*)/)
-      string = match[1] if match
-      vers = Version.new(string)
-      vers.head = true if match
-      vers
+    # @TODO The `from' part of the regexp should be remove before 1.0.0.
+    #
+    def self.from_string(string)
+      if string =~ /HEAD (based on|from) (.*)/
+        v = Version.new($2)
+        v.head = true
+        v
+      else
+        Version.new(string)
+      end
     end
 
     attr_accessor :head
     alias_method :head?, :head
 
     def to_s
-      head? ? "HEAD from #{super}" : super
+      head? ? "HEAD based on #{super}" : super
     end
   end
 end

spec/unit/version_spec.rb

@@ -8,5 +8,21 @@ module Pod
       version.head = true
       version.should.be.head
     end
+
+    it "serializes to and from a string" do
+      version = Version.from_string('1.2.3')
+      version.to_s.should == '1.2.3'
+      version.should.not.be.head
+
+      version = Version.from_string('HEAD based on 1.2.3')
+      version.should.be.head
+      version.to_s.should == 'HEAD based on 1.2.3'
+    end
+
+    it "supports the previous way that a HEAD version was described" do
+      version = Version.from_string('HEAD from 1.2.3')
+      version.should.be.head
+      version.to_s.should == 'HEAD based on 1.2.3'
+    end
   end
 end