[CHEF-3933] support new gem dependency installer return type

in rubygems commit 432fc4818bbf14dfa5e49bbc1950eaa6d3fde133, return type
of dependency_installer's #find_gems_with_sources is changed to return a
Gem::AvailableSet collection instead of an ordered Array.

2 files changed, 27 insertions, 6 deletions

diff --git a/chef/lib/chef/provider/package/rubygems.rb b/chef/lib/chef/provider/package/rubygems.rb
index 2a778fdb14..5b47532597 100644
--- a/chef/lib/chef/provider/package/rubygems.rb
+++ b/chef/lib/chef/provider/package/rubygems.rb
@@ -165,14 +165,23 @@ class Chef
           # Find the newest gem version available from Gem.sources that satisfies
           # the constraints of +gem_dependency+
           def find_newest_remote_version(gem_dependency, *sources)
-            # DependencyInstaller sorts the results such that the last one is
-            # always the one it considers best.
-            spec_with_source = dependency_installer.find_gems_with_sources(gem_dependency).last
+            available_gems = dependency_installer.find_gems_with_sources(gem_dependency)
+            spec, source = if available_gems.respond_to?(:last)
+              # DependencyInstaller sorts the results such that the last one is
+              # always the one it considers best.
+              spec_with_source = available_gems.last
+              spec_with_source && spec_with_source
+            else
+              # Rubygems 2.0 returns a Gem::Available set, which is a
+              # collection of AvailableSet::Tuple structs
+              available_gems.pick_best!
+              best_gem = available_gems.set.first
+              best_gem && [best_gem.spec, best_gem.source]
+            end
 
-            spec = spec_with_source && spec_with_source[0]
-            version = spec && spec_with_source[0].version
+            version = spec && spec.version
             if version
-              logger.debug { "#{@new_resource} found gem #{spec.name} version #{version} for platform #{spec.platform} from #{spec_with_source[1]}" }
+              logger.debug { "#{@new_resource} found gem #{spec.name} version #{version} for platform #{spec.platform} from #{source}" }
               version
             else
               source_list = sources.compact.empty? ? "[#{Gem.sources.to_a.join(', ')}]" : "[#{sources.join(', ')}]"
diff --git a/chef/spec/unit/provider/package/rubygems_spec.rb b/chef/spec/unit/provider/package/rubygems_spec.rb
index b3b7a030db..d7941af76d 100644
--- a/chef/spec/unit/provider/package/rubygems_spec.rb
+++ b/chef/spec/unit/provider/package/rubygems_spec.rb
@@ -95,6 +95,18 @@ describe Chef::Provider::Package::Rubygems::CurrentGemEnvironment do
     @gem_env.candidate_version_from_remote(Gem::Dependency.new('rspec', '>= 0')).should == Gem::Version.new('1.3.0')
   end
 
+  it "finds a matching gem candidate version on rubygems 2.0.0+" do
+    dep = Gem::Dependency.new('rspec', '>= 0')
+    dep_installer = Gem::DependencyInstaller.new
+    @gem_env.stub!(:dependency_installer).and_return(dep_installer)
+    best_gem = mock("best gem match", :spec => gemspec("rspec", Gem::Version.new("1.3.0")), :source => "https://rubygems.org")
+    available_set = mock("Gem::AvailableSet test double")
+    available_set.should_receive(:pick_best!)
+    available_set.should_receive(:set).and_return([best_gem])
+    dep_installer.should_receive(:find_gems_with_sources).with(dep).and_return(available_set)
+    @gem_env.candidate_version_from_remote(Gem::Dependency.new('rspec', '>= 0')).should == Gem::Version.new('1.3.0')
+  end
+
   it "gives the candidate version as nil if none is found" do
     dep = Gem::Dependency.new('rspec', '>= 0')
     latest = []