Merge bundler to standard libraries.

  rubygems 2.7.x depends bundler-1.15.x. This is preparation for
  rubygems and bundler migration.

  * lib/bundler.rb, lib/bundler/*: files of bundler-1.15.4
  * spec/bundler/*: rspec examples of bundler-1.15.4. I applied patches.
    * https://github.com/bundler/bundler/pull/6007
    * Exclude not working examples on ruby repository.
    * Fake ruby interpriter instead of installed ruby.
  * Makefile.in: Added test task named `test-bundler`. This task is only
    working macOS/linux yet. I'm going to support Windows environment later.
  * tool/sync_default_gems.rb: Added sync task for bundler.

  [Feature #12733][ruby-core:77172]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59779 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 25 insertions, 0 deletions

diff --git a/spec/bundler/bundler/stub_specification_spec.rb b/spec/bundler/bundler/stub_specification_spec.rb
new file mode 100644
index 0000000000..f1ddf43bb4
--- /dev/null
+++ b/spec/bundler/bundler/stub_specification_spec.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+require "spec_helper"
+
+RSpec.describe Bundler::StubSpecification do
+  let(:gemspec) do
+    Gem::Specification.new do |s|
+      s.name = "gemname"
+      s.version = "1.0.0"
+      s.loaded_from = __FILE__
+    end
+  end
+
+  let(:with_bundler_stub_spec) do
+    described_class.from_stub(gemspec)
+  end
+
+  if Bundler.rubygems.provides?(">= 2.1")
+    describe "#from_stub" do
+      it "returns the same stub if already a Bundler::StubSpecification" do
+        stub = described_class.from_stub(with_bundler_stub_spec)
+        expect(stub).to be(with_bundler_stub_spec)
+      end
+    end
+  end
+end