10 files changed, 231 insertions, 25 deletions

diff --git a/lib/bubble.rb b/lib/bubble.rb
index 47e990f621..944a6c645e 100644
--- a/lib/bubble.rb
+++ b/lib/bubble.rb
@@ -1,4 +1,5 @@
 require 'pathname'
+require 'yaml'
 require 'bubble/rubygems'
 
 module Bubble
@@ -18,17 +19,23 @@ module Bubble
   class GemfileNotFound < StandardError; end
   class GemNotFound     < StandardError; end
   class VersionConflict < StandardError; end
+  class GemfileError    < StandardError; end
 
   def self.setup(gemfile = nil)
     load(gemfile).setup
   end
 
   def self.load(gemfile = nil)
-    Environment.new(definition(gemfile))
+    Environment.new definition(gemfile)
   end
 
   def self.definition(gemfile = nil)
-    Definition.from_gemfile(gemfile)
+    lockfile = Pathname.new(gemfile || Definition.default_gemfile).dirname.join('omg.yml')
+    if lockfile.exist?
+      Definition.from_lock(lockfile)
+    else
+      Definition.from_gemfile(gemfile)
+    end
   end
 
   def self.home
diff --git a/lib/bubble/cli.rb b/lib/bubble/cli.rb
index 53a9b0707b..d99d2e4a18 100644
--- a/lib/bubble/cli.rb
+++ b/lib/bubble/cli.rb
@@ -8,6 +8,10 @@ Gem.configuration
 
 module Bubble
   class CLI < Thor
+    def self.banner(task)
+      task.formatted_usage(self, false)
+    end
+
     desc "init", "Generates a Gemfile into the current working directory"
     def init
       if File.exist?("Gemfile")
@@ -43,6 +47,11 @@ module Bubble
       Installer.install(Bubble.definition)
     end
 
+    desc "lock", "Locks a resolve"
+    def lock
+      Bubble.load.lock
+    end
+
   private
 
     def with_rescue
diff --git a/lib/bubble/definition.rb b/lib/bubble/definition.rb
index c775593f9d..242e2c0b3f 100644
--- a/lib/bubble/definition.rb
+++ b/lib/bubble/definition.rb
@@ -7,9 +7,7 @@ module Bubble
         raise GemfileNotFound, "`#{gemfile}` not found"
       end
 
-      definition = new
-      Dsl.evaluate(gemfile, definition)
-      definition
+      Dsl.evaluate(gemfile)
     end
 
     def self.default_gemfile
@@ -24,10 +22,76 @@ module Bubble
       raise GemfileNotFound, "The default Gemfile was not found"
     end
 
+    def self.from_lock(lockfile)
+      gemfile_definition = from_gemfile(nil)
+
+      details = YAML.load_file(lockfile)
+      sources = details["sources"].map do |args|
+        name, options = args.to_a.flatten
+        Bubble::Source.const_get(name).new(options)
+      end
+
+      dependencies = details["dependencies"].map do |args|
+        Gem::Dependency.new(*args.to_a.flatten)
+      end
+
+      specs = details["specs"].map do |args|
+        Gem::Dependency.new(*args.to_a.flatten)
+      end
+
+      locked_definition = new(dependencies, sources, specs)
+
+      raise GemfileError unless gemfile_definition.matches?(locked_definition) &&
+                                locked_definition.matches?(gemfile_definition)
+
+      locked_definition
+    end
+
     attr_reader :dependencies, :sources
 
-    def initialize
-      @dependencies, @sources = [], Gem.sources.map { |s| Source::Rubygems.new(:uri => s) }
+    def initialize(dependencies, sources, resolved_dependencies = nil)
+      @dependencies = dependencies
+      @sources = sources
+
+      if resolved_dependencies
+        @specs = resolved_dependencies.map do |dep|
+          index.search(dep).first
+        end
+      end
+    end
+
+    def matches?(other)
+      dependencies.all? do |dep|
+        dep =~ other.specs.find {|spec| spec.name == dep.name }
+      end
+    end
+
+    def specs
+      @specs ||= Resolver.resolve(dependencies, index)
+    end
+
+    def index
+      @index ||= begin
+        index = Index.new
+        sources.reverse_each do |source|
+          index.merge! source.local_specs
+        end
+        index
+      end
+    end
+
+    def to_yaml(options = {})
+      details.to_yaml(options)
+    end
+
+  private
+
+    def details
+      {}.tap do |det|
+        det["sources"] = sources.map { |s| { s.class.name.split("::").last => s.options} }
+        det["specs"] = specs.map { |s| {s.name => s.version.to_s} }
+        det["dependencies"] = dependencies.map { |d| {d.name => d.version_requirements.to_s} }
+      end
     end
   end
 end
\ No newline at end of file
diff --git a/lib/bubble/dsl.rb b/lib/bubble/dsl.rb
index 02668a2db7..7459b97c5c 100644
--- a/lib/bubble/dsl.rb
+++ b/lib/bubble/dsl.rb
@@ -2,14 +2,15 @@ module Bubble
   class DslError < StandardError; end
 
   class Dsl
-    def self.evaluate(gemfile, definition)
-      builder = new(definition)
+    def self.evaluate(gemfile)
+      builder = new
       builder.instance_eval(File.read(gemfile.to_s), gemfile.to_s, 1)
-      definition
+      builder.to_definition
     end
 
-    def initialize(definition)
-      @definition = definition
+    def initialize
+      @sources = Gem.sources.map { |s| Source::Rubygems.new(:uri => s) }
+      @dependencies = []
       @git = nil
       @git_sources = {}
     end
@@ -18,7 +19,7 @@ module Bubble
       options = Hash === args.last ? args.pop : {}
       version = args.last || ">= 0"
 
-      @definition.dependencies << Dependency.new(name, version, options)
+      @dependencies << Dependency.new(name, version, options)
     end
 
     def source(source)
@@ -28,7 +29,7 @@ module Bubble
       else source
       end
 
-      @definition.sources << source
+      @sources << source
     end
 
     def path(path, options = {})
@@ -39,5 +40,9 @@ module Bubble
       source Source::Git.new(options.merge(:uri => uri))
     end
 
+    def to_definition
+      Definition.new(@dependencies, @sources)
+    end
+
   end
 end
\ No newline at end of file
diff --git a/lib/bubble/environment.rb b/lib/bubble/environment.rb
index a06bea85f4..adcb3e3bd7 100644
--- a/lib/bubble/environment.rb
+++ b/lib/bubble/environment.rb
@@ -1,5 +1,9 @@
 module Bubble
   class Environment
+    def self.from_gemfile(gemfile)
+      new Definition.from_gemfile(gemfile)
+    end
+
     def initialize(definition)
       @definition = definition
     end
@@ -16,18 +20,19 @@ module Bubble
       @definition.dependencies
     end
 
+    def lock
+      yml = @definition.to_yaml
+      File.open("#{Definition.default_gemfile.dirname}/omg.yml", 'w') do |f|
+        f.puts yml
+      end
+    end
+
     def specs
-      @specs ||= Resolver.resolve(dependencies, index)
+      @definition.specs
     end
 
     def index
-      @index ||= begin
-        index = Index.new
-        @definition.sources.reverse_each do |source|
-          index.merge! source.local_specs
-        end
-        index
-      end
+      @definition.index
     end
 
   end
diff --git a/lib/bubble/source.rb b/lib/bubble/source.rb
index 137a247cb1..1e347a92f0 100644
--- a/lib/bubble/source.rb
+++ b/lib/bubble/source.rb
@@ -4,9 +4,10 @@ require "digest/sha1"
 module Bubble
   module Source
     class Rubygems
-      attr_reader :uri
+      attr_reader :uri, :options
 
       def initialize(options = {})
+        @options = options
         @uri = options[:uri]
         @uri = URI.parse(@uri) unless @uri.is_a?(URI)
         raise ArgumentError, "The source must be an absolute URI" unless @uri.absolute?
@@ -52,9 +53,10 @@ module Bubble
     end
 
     class Path
-      attr_reader :path
+      attr_reader :path, :options
 
       def initialize(options)
+        @options = options
         @glob = options[:glob] || "{,*/}*.gemspec"
         @path = options[:path]
       end
@@ -86,11 +88,16 @@ module Bubble
       attr_reader :uri, :ref
 
       def initialize(options)
+        @options = options
         @glob = options[:glob] || "{,*/}*.gemspec"
         @uri  = options[:uri]
         @ref  = options[:ref] || options[:branch] || 'master'
       end
 
+      def to_yaml(options = {})
+        { :uri => @uri.to_s, :ref => @ref, :glob => @glob }.to_yaml
+      end
+
       def path
         Bubble.install_path.join("#{base_name}-#{uri_hash}-#{ref}")
       end
diff --git a/spec/lock/gems_spec.rb b/spec/lock/gems_spec.rb
new file mode 100644
index 0000000000..25d3baddf8
--- /dev/null
+++ b/spec/lock/gems_spec.rb
@@ -0,0 +1,23 @@
+require File.expand_path('../../spec_helper', __FILE__)
+
+describe "bbl lock with gems" do
+  before :each do
+    in_app_root
+  end
+
+  it "locks the gemfile resolve to the versions available at the time" do
+    gemfile <<-G
+      gem "rack"
+    G
+
+    system_gems "rack-0.9.1" do
+      bbl :lock
+    end
+
+    system_gems "rack-1.0.0", "rack-0.9.1" do
+      should_be_available "rack 0.9.1"
+    end
+  end
+
+  it "includes the ruby version as a dependency of the lock"
+end
\ No newline at end of file
diff --git a/spec/runtime/load_spec.rb b/spec/runtime/load_spec.rb
index 9b60673b7c..2813f1af92 100644
--- a/spec/runtime/load_spec.rb
+++ b/spec/runtime/load_spec.rb
@@ -37,4 +37,88 @@ describe "Bubble.load" do
       Bubble.load("omg.rb")
     }.should raise_error(Bubble::GemfileNotFound, /omg\.rb/)
   end
+
+  describe "when locked" do
+    before :each do
+      system_gems "rack-1.0.0", "activesupport-2.3.2", "activerecord-2.3.2", "activerecord-2.3.1"
+    end
+
+    it "raises an exception if the Gemfile adds a dependency" do
+      gemfile <<-G
+        gem "rack"
+      G
+
+      bbl :lock
+
+      gemfile <<-G
+        gem "rack"
+        gem "activerecord"
+      G
+
+      lambda { Bubble.load }.should raise_error(Bubble::GemfileError)
+    end
+
+    it "raises an exception if the Gemfile removes a dependency" do
+      gemfile <<-G
+        gem "rack"
+        gem "activerecord"
+      G
+
+      bbl :lock
+
+      gemfile <<-G
+        gem "rack"
+      G
+
+      lambda { Bubble.load }.should raise_error(Bubble::GemfileError)
+    end
+
+    it "raises an exception if the Gemfile changes a dependency in an incompatible way" do
+      gemfile <<-G
+        gem "rack"
+        gem "activerecord"
+      G
+
+      bbl :lock
+
+      gemfile <<-G
+        gem "rack"
+        gem "activerecord", "2.3.1"
+      G
+
+      lambda { Bubble.load }.should raise_error(Bubble::GemfileError)
+    end
+
+    it "raises an exception if the Gemfile replaces a root with a child dep of the root" do
+      gemfile <<-G
+        gem "rack"
+        gem "activerecord"
+      G
+
+      bbl :lock
+
+      gemfile <<-G
+        gem "rack"
+        gem "activesupport"
+      G
+
+      lambda { Bubble.load }.should raise_error(Bubble::GemfileError)
+    end
+
+    it "works if the Gemfile changes in a compatible way" do
+      gemfile <<-G
+        gem "rack"
+        gem "activerecord", "2.3.2"
+      G
+
+      bbl :lock
+
+      gemfile <<-G
+        gem "rack"
+        gem "activerecord", ">= 2.0.0"
+      G
+
+      lambda { Bubble.load }.should_not raise_error(Bubble::GemfileError)
+    end
+  end
 end
\ No newline at end of file
diff --git a/spec/support/builders.rb b/spec/support/builders.rb
index 43612947e1..5404bd43aa 100644
--- a/spec/support/builders.rb
+++ b/spec/support/builders.rb
@@ -23,7 +23,7 @@ module Spec
         build_gem "actionpack",     "2.3.2" do |s|
           s.add_dependency "activesupport", "2.3.2"
         end
-        build_gem "activerecord",   "2.3.2" do |s|
+        build_gem "activerecord",   ["2.3.1", "2.3.2"] do |s|
           s.add_dependency "activesupport", "2.3.2"
         end
         build_gem "actionmailer",   "2.3.2" do |s|
diff --git a/spec/support/matchers.rb b/spec/support/matchers.rb
index 948de5a797..edd7215074 100644
--- a/spec/support/matchers.rb
+++ b/spec/support/matchers.rb
@@ -22,5 +22,7 @@ module Spec
         Gem::Version.new(out).should == Gem::Version.new(version)
       end
     end
+
+    alias should_be_available should_be_installed
   end
 end
\ No newline at end of file