for generateProto, delete the output directory before calling protoc

[devinrsmith]

Fix for #331 / #332

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[devinrsmith]

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[joschi]

I've been running into the same problem and worked around it as described in #331 (comment).

Any chance of getting this PR merged?

[voidzcy]

I've been running into the same problem and worked around it as described in #331 (comment).

Any chance of getting this PR merged?

We can't get this merged as long as people are pointing generatedFilesBaseDir to their custom directory for generated files. People used to use it for putting generate files together with other files. We cannot just wipe the directory (see #332).

For general cases, you should at most need a clean build and that will delete unnecessary files after you proto definition changes.

We'd probably change the actual implementation of generatedFilesBaseDir to use a Copy task that copies generated files to the custom directory. Then we are free wipe the task's output directory while keeping existing users of generatedFilesBaseDir safe.

[mattwelke]

For general cases, you should at most need a clean build and that will delete unnecessary files after you proto definition changes.

So the solution here would be to do a ./gradlew clean build for example? The clean deletes the old generated Java source code, and the build creates new code?

[ejona86]

#636 was merged in favor of this one. This has been a long-time pain, so I appreciate the effort to get it fixed.