Model.Builder builder = Model.newBuilder(model);
        modelMerger.mergeModel_ModelVersion(builder, model, parent, false, null);
        assertNull(builder.build().getModelVersion());

        model = Model.newBuilder().modelVersion("5.0.0").build();
        builder = Model.newBuilder(model);
        modelMerger.mergeModel_ModelVersion(builder, model, parent, false, null);

        // don't merge
    }

    @Override
    protected void mergeModel_Contributors(
            Model.Builder builder, Model target, Model source, boolean sourceDominant, Map<Object, Object> context) {
        // don't merge
    }

    @Override
    protected void mergeModel_Developers(

    }

    @Override
    protected Model mergeModel(Model target, Model source, boolean sourceDominant, Map<Object, Object> context) {
        context.put(ARTIFACT_ID, target.getArtifactId());

        return super.mergeModel(target, source, sourceDominant, context);
    }

    @Override
    protected void mergeModel_Name(

      for (Range<Integer> range2 : RANGES) {
        for (Range<Integer> range3 : RANGES) {
          Map<Integer, Integer> model = Maps.newHashMap();
          mergeModel(model, range1, 1, Integer::sum);
          mergeModel(model, range2, 2, Integer::sum);
          mergeModel(model, range3, 3, Integer::sum);
          RangeMap<Integer, Integer> test = TreeRangeMap.create();
          test.merge(range1, 1, Integer::sum);

pkg fmt, type Stringer interface, String() string
pkg go/ast, const Bad ObjKind
pkg go/ast, const Con ObjKind
pkg go/ast, const FilterFuncDuplicates MergeMode
pkg go/ast, const FilterImportDuplicates MergeMode
pkg go/ast, const FilterUnassociatedComments MergeMode
pkg go/ast, const Fun ObjKind
pkg go/ast, const Lbl ObjKind
pkg go/ast, const Pkg ObjKind
pkg go/ast, const RECV ChanDir
pkg go/ast, const SEND ChanDir