compile:doc results in compilation error for static inner classes in java

[NAJ10]

ReproduceScalaDoc.zip

When "sbt compile:doc" is run on the attached mixed Java/Scala sbt project (unzip ReproduceScalaDoc.zip) the following error is seen

[error] /home/user/Development/repository/ReproduceScalaDoc/src/main/java/example/Trade.java:13: not found: type Identifier
[error]     public Trade(Identifier id) {
[error]                  ^
[info] No documentation generated with unsuccessful compiler run

sbt compile produces no error.

This is seen with Scala versions 2.12.0, 2.12.1 and 2.12.2. The problem does not occur on Scala 2.11.11.

This example has been distilled from our applications very large code base which is a mixture of Scala and Java. The application is the product of over 15 years work. The problem was found in the course of migrating from Scala 2.11 to Scala 2.12.

It seems like static inner classes are not being handled correctly. A similar/identical problem occurs when enums are nested inside a Java class.

[SethTisue]

workaround: you can restore the 2.11 behavior with scalacOptions in (Compile, doc) += "-no-java-comments" (as per the 2.12.0 release notes)

[lrytz]

This is a duplicate of #9111, it works if you use specify the outer name when referencing class Trade

    public Trade(Trade.Identifier id) {