Fix NoMethodError on bundler/inline environment

  Fixes #2041

  raw_require_paths returns nil variable when running with
  bundle/inline environment.

Author: hsbt

lib/rubygems/basic_specification.rb

@@ -275,10 +275,14 @@ def matches_for_glob glob # TODO: rename?
   # for this spec.
 
   def lib_dirs_glob
-    dirs = if self.raw_require_paths.size > 1 then
-             "{#{self.raw_require_paths.join(',')}}"
+    dirs = if self.raw_require_paths
+             if self.raw_require_paths.size > 1 then
+               "{#{self.raw_require_paths.join(',')}}"
+             else
+               self.raw_require_paths.first
+             end
            else
-             self.raw_require_paths.first
+            "lib" # default value for require_paths for bundler/inline
            end
 
     "#{self.full_gem_path}/#{dirs}".dup.untaint

test/rubygems/test_gem_stub_specification.rb

@@ -110,6 +110,18 @@ def test_matches_for_glob
     assert_equal code_rb, stub.matches_for_glob('code*').first
   end
 
+  def test_matches_for_glob_with_bundler_inline
+    stub = stub_with_extension
+    code_rb = File.join stub.gem_dir, 'lib', 'code.rb'
+    FileUtils.mkdir_p File.dirname code_rb
+    FileUtils.touch code_rb
+
+    stub.stub(:raw_require_paths, nil) do
+      assert_equal code_rb, stub.matches_for_glob('code*').first
+    end
+  end
+
+
   def test_missing_extensions_eh
     stub = stub_with_extension do |s|
       extconf_rb = File.join s.gem_dir, s.extensions.first