[rubygems/rubygems] Stop bundler eagerly loading all specs with exts

We were setting the wrong `extension_dir` for git specs stubs

Additionally, the call to `self.extension_dir` was loading the
remote spec, which was avoidable since the stub had an extension dir
(and in fact its #gem_build_complete_path does exactly what we want
anyway)

Finally, now set the base_dir when loading the remote_spec from a
stub specification, since the git source sets the base dir for stubs
based on where the spec _will_ be installed to, and we want to preserve
that so the base_dir for the loaded spec & the stub are the same

https://github.com/rubygems/rubygems/commit/a94acb465b

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/bundler/stub_specification.rb b/lib/bundler/stub_specification.rb
index 88a4257fa4..6f4264e561 100644
--- a/lib/bundler/stub_specification.rb
+++ b/lib/bundler/stub_specification.rb
@@ -16,7 +16,8 @@ module Bundler
       # Stub has no concept of source, which means that extension_dir may be wrong
       # This is the case for git-based gems. So, instead manually assign the extension dir
       return unless source.respond_to?(:extension_dir_name)
-      path = File.join(stub.extensions_dir, source.extension_dir_name)
+      unique_extension_dir = [source.extension_dir_name, File.basename(full_gem_path)].uniq.join("-")
+      path = File.join(stub.extensions_dir, unique_extension_dir)
       stub.extension_dir = File.expand_path(path)
     end
 
@@ -56,7 +57,7 @@ module Bundler
     end
 
     def gem_build_complete_path
-      File.join(extension_dir, "gem.build_complete")
+      stub.gem_build_complete_path
     end
 
     def default_gem?
@@ -108,6 +109,7 @@ module Bundler
         end
 
         rs.source = source
+        rs.base_dir = stub.base_dir
 
         rs
       end