DuplicateOptionAnnotationsException when a nested group is defined inside a mixin

[teoincontatto]

With version 4.0.2-SNAPSHOT I am facing a DuplicateOptionAnnotationsException in a particular use case. The mixin is using a nested group inside of a group. I managed to generate a simple test case that reproduce the issue:

• Test code:

@picocli.CommandLine.Command(name = "test-with-mixin-and-nested-group",
    description = "Picocli section test with mixin and nested group.",
    abbreviateSynopsis = true,
    sortOptions = false)
public class Test {
  @Mixin
  TestConfig testConfig = new TestConfig();

  private static class TestConfig {
    @ArgGroup(validate = false, heading = "A1%n")
    private final A1 a1 = new A1();

    private static class A1 {
      @ArgGroup(exclusive = true)
      private final NestedA1 nestedA1 = new NestedA1();

      private static class NestedA1 {
        @Option(names = {"-ta1", "--test-a1"})
        private String testA1;
        @Option(names = {"-ta2", "--test-a2"})
        private String testA2;
      }
    }

    @ArgGroup(validate = false, heading = "A2%n")
    private final A2 a2 = new A2();

    private static class A2 {
      @Option(names = {"-tb1", "--test-b1"})
      private String testB1;
      @Option(names = {"-tb2", "--test-b2"})
      private String testB2;
    }
  }

  /**
   * Picocli test.
   */
  public static void main(String[] args) {
    new CommandLine(new Test()).usage(System.out);
  }
}

• Output:

picocli.CommandLine$DuplicateOptionAnnotationsException: Option name '-ta2' is used by both field String com.ongres.egres.TestPicocliHeadingSection$TestWithNestedMixin$TestConfig$A1$NestedA1.testA2 and field String com.ongres.egres.TestPicocliHeadingSection$TestWithNestedMixin$TestConfig$A1$NestedA1.testA2
	at picocli.CommandLine$DuplicateOptionAnnotationsException.create(CommandLine.java:15027)
	at picocli.CommandLine$DuplicateOptionAnnotationsException.access$1700(CommandLine.java:15021)
	at picocli.CommandLine$Model$CommandSpec.addOption(CommandLine.java:5381)
	at picocli.CommandLine$Model$CommandSpec.addMixin(CommandLine.java:5567)
	at picocli.CommandLine$Model$CommandReflection.initFromAnnotatedTypedMembers(CommandLine.java:9641)
	at picocli.CommandLine$Model$CommandReflection.initFromAnnotatedFields(CommandLine.java:9621)
	at picocli.CommandLine$Model$CommandReflection.extractCommandSpec(CommandLine.java:9532)
	at picocli.CommandLine$Model$CommandSpec.forAnnotatedObject(CommandLine.java:5116)
	at picocli.CommandLine.<init>(CommandLine.java:223)
	at picocli.CommandLine.<init>(CommandLine.java:196)
	at Test.main(Test.java:45)

Originally posted by @teoincontatto in #776 (comment)

[remkop]

Thank you again for raising this!
I think I know what the issue is and will commit a fix shortly.

[remkop]

Fixed in master.
Can you verify?

I plan to do a picocli-4.0.2 release that includes this fix later this week.

[teoincontatto]

Confirmed!

[remkop]

Thanks for the confirmation!