Fixes broken test

Wanting to help out, I was on the outlook for something easy
to fix in bundler. I stumbled upon this issue 4854, which was already
tackled by b-ggs but somehow not merged yet. I went on to check whether
I could do something. Here's what I've come up with:

b-ggs' PR included everything to solve the issue, but introduced the
use of ```Bundler.app_cache``` in the resolver. This works out just
fine until you run ```bundle plugin install```, which does not seem to
require a Gemfile. ```Bundler.app_cache``` however calls ```root```,
which then again tries to find a Gemfile. This obviously fails and
raises a ```GemfileNotFound``` exception. The error message
"Could not locate Gemfile or .bundle/ directory" starts very similar
to the one expected in the failing test ("Could not find"). This
however, is a completely different error.

The solution is now is to rescue the GemfileNotFound error when it
comes up to here.

All credit for solving the issue goes to b-ggs and his PR here:
bundler/bundler pull:4865

Fix rubocop offense

1 files changed, 6 insertions, 1 deletions

diff --git a/lib/bundler/resolver.rb b/lib/bundler/resolver.rb
index e636e1f815..1dbe5b9921 100644
--- a/lib/bundler/resolver.rb
+++ b/lib/bundler/resolver.rb
@@ -250,6 +250,7 @@ module Bundler
     end
 
     def search_for(dependency)
+      puts "Searching for #{dependency}"
       platform = dependency.__platform
       dependency = dependency.dep unless dependency.is_a? Gem::Dependency
       search = @search_for[dependency] ||= begin
@@ -365,7 +366,11 @@ module Bundler
                        "Source does not contain any versions of '#{requirement}'"
                      end
         else
-          cache_message = Bundler.app_cache.exist? ? " or in gems cached in vendor/cache" : ""
+          cache_message = begin
+                            " or in gems cached in #{Bundler.settings.app_cache_path}" if Bundler.app_cache.exist?
+                          rescue GemfileNotFound
+                            nil
+                          end
           message = "Could not find gem '#{requirement}' in any of the gem sources " \
             "listed in your Gemfile#{cache_message}."
         end