Parse Java annotations on wildcard type arguments

[mkurz]

Java permits type-use annotations before wildcard type arguments, for example

Function<@Nullable ? super String, @Nullable ? extends Object>

Reproduce

You can use this repo's test files:

$ cd tests/pos/java-annotated-wildcards/

$ scala -version
Scala code runner version: 1.12.4
Scala version (default): 3.8.3

$ scalac -usejavacp Nullable.java Test.java 
-- Error: Test.java:4:21 ---------------------------------------------------------------------------------------------------------------------------
4 |  Function<@Nullable ? super String, @Nullable ? extends Object> mappingFunction();
  |                     ^^^^^^^^
  |                     illegal start of type
-- Error: Test.java:4:82 ---------------------------------------------------------------------------------------------------------------------------
4 |  Function<@Nullable ? super String, @Nullable ? extends Object> mappingFunction();
  |                                                                                  ^
  |                                                                                  null expected but ';' found.
  |
5 |}
2 errors found

Java however can compile it:

$ java -version
openjdk version "1.8.0_492"
OpenJDK Runtime Environment (Temurin)(build 1.8.0_492-b09)
OpenJDK 64-Bit Server VM (Temurin)(build 25.492-b09, mixed mode)

$ javac Nullable.java Test.java 
$ ls -1 *.class
Nullable.class
Test.class

How much have you relied on LLM-based tools in this contribution?

Not at all (update: after the GitHub actions jobs failed I used codex for analysing the code and find out what broke, that lead to force push)

How was the solution tested?

New automated tests (including the issue's reproducer)
Plus Manual tests

See also

• Fix annotations being not expected in the middle of an array type by java parser #22391
  • basically same kind of fix

[mkurz]

Backport for Scala 2:

• Parse Java annotations on wildcard type arguments scala#11252