add Bundler.clean_system and Bundler.clean_exec

lib/bundler.rb

@@ -200,6 +200,14 @@ def with_clean_env
       end
     end
 
+    def clean_system(*args)
+      with_clean_env { Kernel.system(*args) }
+    end
+
+    def clean_exec(*args)
+      with_clean_env { Kernel.exec(*args) }
+    end
+
     def default_gemfile
       SharedHelpers.default_gemfile
     end

spec/runtime/with_clean_env_spec.rb

@@ -45,3 +45,34 @@
   end
 
 end
+
+describe "Bundler.clean_system" do
+
+  it "runs system inside with_clean_env" do
+    bundle_path = Bundler::ORIGINAL_ENV['BUNDLE_PATH']
+    Bundler::ORIGINAL_ENV['BUNDLE_PATH'] = "./Gemfile"
+
+    Bundler.clean_system(%{echo 'if [ "$BUNDLE_PATH" = "" ]; then exit 42; else exit 1; fi' | /bin/sh})
+    $?.exitstatus.should == 42
+
+    Bundler::ORIGINAL_ENV['BUNDLE_PATH'] = bundle_path
+  end
+
+end
+
+describe "Bundler.clean_exec" do
+
+  it "runs exec inside with_clean_env" do
+    bundle_path = Bundler::ORIGINAL_ENV['BUNDLE_PATH']
+    Bundler::ORIGINAL_ENV['BUNDLE_PATH'] = "./Gemfile"
+
+    pid = Kernel.fork do
+      Bundler.clean_exec(%{echo 'if [ "$BUNDLE_PATH" = "" ]; then exit 42; else exit 1; fi' | /bin/sh})
+    end
+    Process.wait(pid)
+    $?.exitstatus.should == 42
+
+    Bundler::ORIGINAL_ENV['BUNDLE_PATH'] = bundle_path
+  end
+
+end