buck.generatedSourcePath is not reported for java_test rule

Created by: elucash

Given the JSON output of commands such as

buck targets "//..." --json --show-output

Apparently, for java_test rules which have plugins/annotation processors enabled and successfully generating and compiling additional Java classes, the rule JSON doesn't return buck.generatedSourcePath field as it does for say java_library. Under closer inspection, the internal location of the generated files folder itself is slightly different than for libraries, it looks like buck-out/annotation/{path}/__{name}#testsjar_gen__ and this suggests that different storage/mechanism is used for java_test. However, It would still be great if JSON output of test rule still returns buck.generatedSourcePath field pointing to an internal path in the same manner as it does for java_library.

Thank you!