Merge pull request #3896 from EduardoBautista/fix-missing-source

Print a warning when a gem can't be cached due to a missing source

2 files changed, 15 insertions, 1 deletions

diff --git a/lib/bundler/source/rubygems.rb b/lib/bundler/source/rubygems.rb
index d15362b9aa..a9b10f5936 100644
--- a/lib/bundler/source/rubygems.rb
+++ b/lib/bundler/source/rubygems.rb
@@ -189,7 +189,11 @@ module Bundler
         cached_path = cached_path(spec)
         if cached_path.nil?
           remote_spec = remote_specs.search(spec).first
-          cached_path = fetch_gem(remote_spec)
+          if remote_spec
+            cached_path = fetch_gem(remote_spec)
+          else
+            Bundler.ui.warn "#{spec.full_name} is built in to Ruby, and can't be cached because your Gemfile doesn't have any sources that contain it."
+          end
         end
         cached_path
       end
diff --git a/spec/cache/gems_spec.rb b/spec/cache/gems_spec.rb
index 1d26f5011b..fef6e0fce6 100644
--- a/spec/cache/gems_spec.rb
+++ b/spec/cache/gems_spec.rb
@@ -116,6 +116,16 @@ describe "bundle cache" do
       bundle "install --local"
       should_be_installed("builtin_gem_2 1.0.2")
     end
+
+    it "errors if the builtin gem isn't available to cache" do
+      install_gemfile <<-G
+        gem 'builtin_gem', '1.0.2'
+      G
+
+      bundle :cache
+      expect(exitstatus).to_not eq(0) if exitstatus
+      expect(out).to include("builtin_gem-1.0.2 is built in to Ruby, and can't be cached")
+    end
   end
 
   describe "when there are also git sources" do