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, 80 insertions, 0 deletions

diff --git a/spec/bundler/bundler/environment_preserver_spec.rb b/spec/bundler/bundler/environment_preserver_spec.rb
new file mode 100644
index 0000000000..41d2650055
--- /dev/null
+++ b/spec/bundler/bundler/environment_preserver_spec.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+require "spec_helper"
+
+RSpec.describe Bundler::EnvironmentPreserver do
+  let(:preserver) { described_class.new(env, ["foo"]) }
+
+  describe "#backup" do
+    let(:env) { { "foo" => "my-foo", "bar" => "my-bar" } }
+    subject { preserver.backup }
+
+    it "should create backup entries" do
+      expect(subject["BUNDLER_ORIG_foo"]).to eq("my-foo")
+    end
+
+    it "should keep the original entry" do
+      expect(subject["foo"]).to eq("my-foo")
+    end
+
+    it "should not create backup entries for unspecified keys" do
+      expect(subject.key?("BUNDLER_ORIG_bar")).to eq(false)
+    end
+
+    it "should not affect the original env" do
+      subject
+      expect(env.keys.sort).to eq(%w(bar foo))
+    end
+
+    context "when a key is empty" do
+      let(:env) { { "foo" => "" } }
+
+      it "should not create backup entries" do
+        expect(subject.key?("BUNDLER_ORIG_foo")).to eq(false)
+      end
+    end
+
+    context "when an original key is set" do
+      let(:env) { { "foo" => "my-foo", "BUNDLER_ORIG_foo" => "orig-foo" } }
+
+      it "should keep the original value in the BUNDLER_ORIG_ variable" do
+        expect(subject["BUNDLER_ORIG_foo"]).to eq("orig-foo")
+      end
+
+      it "should keep the variable" do
+        expect(subject["foo"]).to eq("my-foo")
+      end
+    end
+  end
+
+  describe "#restore" do
+    subject { preserver.restore }
+
+    context "when an original key is set" do
+      let(:env) { { "foo" => "my-foo", "BUNDLER_ORIG_foo" => "orig-foo" } }
+
+      it "should restore the original value" do
+        expect(subject["foo"]).to eq("orig-foo")
+      end
+
+      it "should delete the backup value" do
+        expect(subject.key?("BUNDLER_ORIG_foo")).to eq(false)
+      end
+    end
+
+    context "when no original key is set" do
+      let(:env) { { "foo" => "my-foo" } }
+
+      it "should keep the current value" do
+        expect(subject["foo"]).to eq("my-foo")
+      end
+    end
+
+    context "when the original key is empty" do
+      let(:env) { { "foo" => "my-foo", "BUNDLER_ORIG_foo" => "" } }
+
+      it "should keep the current value" do
+        expect(subject["foo"]).to eq("my-foo")
+      end
+    end
+  end
+end