During a plugin install, if the plugin is already installed and
activated, no specification will be returned as there was nothing
new installed. In this situation, look for the requested plugin
within the activated specifications. If it is found, then proceed
since the plugin is installed. If it is not found, return an error.
This pull request adds an enhancement to the internal Bundler class
to cache solution sets. This prevents Vagrant from generating a
solution for configured plugins on every run. Modifications to
the configured plugin list (global or local) will result in the
cached solution being invalidatd and resolved again.
Also included is the removal of the GEMRC modifications required
for Windows.
Due to the Vagrantfile being loaded prior to plugin loading to determine
project local plugin information the Vagrant.has_plugin? helper will always
return false when the Vagrantfile is first loaded. To prevent this behavior
we can check for plugins in the plugin data files prior to the plugins
being loaded, and after they have been loaded we can fallback to the
original specification based check.
When using prerelease gems we need to ensure we store the gem version otherwise Bundler won't use the correct gem version since prerelease gems are not available by default. By storing the gem version for prerelease gems, we allow Bundler to properly resolve prerelease gems and not give potentially confusing errors to Vagrant users using prerelease plugins.
