Prior to this commit, it was possible to create a DefaultGenerationContext
based on a ClassNameGenerator and GeneratedFiles; however, there was no way
to create a DefaultGenerationContext that reused an existing RuntimeHints
instance which is necessary in certain use cases -- for example, in the
TestContext framework where multiple GenerationContexts are created
based on shared instances of GeneratedFiles and RuntimeHints.
This commit addresses this by introducing a public
DefaultGenerationContext(ClassNameGenerator,GeneratedFiles,RuntimeHints)
constructor.