Incremental compilation

[keeganwitt]

No description provided.

[keeganwitt]

I've been studying the Maven Compiler plugin for inspiration. They do matching of sources to classes to detect changes (comparing the timestamps between the two). But this is tougher to do in Groovy, given the source filenames don't have to match the compiled class name. I'm trying to come up with an alternative strategy for detecting whether recompilation is needed due to updated sources.

One option would be to save a list of source files and last modified timestamps, then check every source file for a newer timestamp than the timestamp saved. But I'm a little concerned about the performance of this approach.

[keeganwitt]

Some additional possible considerations:

• Is there any impact around MGROOVY-187?
• Is there any risks introduced by the lack of idempotency of the Groovy compiler (I think not)?
• Can we handle changes to other JVM languages in a joint compilation scenario (Scala/Clojure/Kotlin/etc)?
• Can we handle changes in generated sources?
• Can we handle changes to jars in a lib directory?