Make Bundler never instantiate development dependencies #8486
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What was the end-user or developer problem that led to this PR?
None, just want to make the code simpler and error messages read a bit better.
What is your fix for the problem, implemented in this PR?
Bundler does not really have a concept of "development dependencies", like RubyGems has. Bundler has the more generic concept of "groups".
Under the hood, the
gemspecDSL will put gemspec development dependencies under a:developmentGemfile group, but there's no reason to instantiate these as development dependencies, they are regular runtime dependencies, except that they belong in a group named :development.By never instantiating development dependencies at all, we avoid having to introduce hacks to "undo" the type Bundler does not know about, and I also think the error messages read better.
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