1 files changed, 24 insertions, 1 deletions
diff --git a/lib/rubygems/request_set/lockfile.rb b/lib/rubygems/request_set/lockfile.rb
index 0073bfdcc5..d70b09f7a2 100644
--- a/lib/rubygems/request_set/lockfile.rb
+++ b/lib/rubygems/request_set/lockfile.rb
@@ -1,3 +1,8 @@
+##
+# Parses a gem.deps.rb.lock file and constructs a LockSet containing the
+# dependencies found inside.  If the lock file is missing no LockSet is
+# constructed.
+
 class Gem::RequestSet::Lockfile
 
   ##
@@ -100,7 +105,7 @@ class Gem::RequestSet::Lockfile
     out << nil
   end
 
-  def relative_path_from(dest, base)
+  def relative_path_from dest, base # :nodoc:
     dest = File.expand_path(dest)
     base = File.expand_path(base)
 
@@ -263,6 +268,9 @@ class Gem::RequestSet::Lockfile
     get while not @tokens.empty? and peek.first == type
   end
 
+  ##
+  # The contents of the lock file.
+
   def to_s
     @set.resolve
 
@@ -293,6 +301,10 @@ class Gem::RequestSet::Lockfile
     [byte_offset - @line_pos, @line]
   end
 
+  ##
+  # Converts a lock file into an Array of tokens.  If the lock file is missing
+  # an empty Array is returned.
+
   def tokenize # :nodoc:
     @line     = 0
     @line_pos = 0
@@ -343,6 +355,8 @@ class Gem::RequestSet::Lockfile
     end
 
     @tokens
+  rescue Errno::ENOENT
+    @tokens
   end
 
   ##
@@ -352,5 +366,14 @@ class Gem::RequestSet::Lockfile
     @tokens.unshift @current_token
   end
 
+  ##
+  # Writes the lock file alongside the gem dependencies file
+
+  def write
+    open "#{@gem_deps_file}.lock", 'w' do |io|
+      io.write to_s
+    end
+  end
+
 end