### Question:
FeatureReaderBuilder { public FeatureReaderBuilder headRef(@NonNull String headRef) { this.headRef = headRef; return this; } FeatureReaderBuilder(Context leftRepo, Context rightRepo, RevFeatureType nativeType,
            NodeRef typeRef); FeatureReaderBuilder ignoreIndex(); static FeatureReaderBuilder builder(Context repo, RevFeatureType nativeType,
            NodeRef typeRef); static FeatureReaderBuilder builder(@NonNull Context leftRepo,
            @NonNull Context rightRepo, @NonNull RevFeatureType nativeType,
            @NonNull NodeRef typeRef); FeatureReaderBuilder oldHeadRef(@Nullable String oldHeadRef); FeatureReaderBuilder changeType(@NonNull ChangeType changeType); FeatureReaderBuilder headRef(@NonNull String headRef); FeatureReaderBuilder propertyNames(@Nullable String... propertyNames); FeatureReaderBuilder filter(@NonNull Filter filter); FeatureReaderBuilder screenMap(@Nullable ScreenMap screenMap); FeatureReaderBuilder geometryFactory(@Nullable GeometryFactory geometryFactory); FeatureReaderBuilder simplificationDistance(@Nullable Double simplifDistance); FeatureReaderBuilder sortBy(@Nullable SortBy... sortBy); FeatureReaderBuilder offset(@Nullable Integer offset); FeatureReaderBuilder limit(@Nullable Integer limit); WalkInfo buildTreeWalk(); FeatureReader<SimpleFeatureType, SimpleFeature> build(); SimpleFeatureType resolveFullSchema(); FeatureReaderBuilder targetSchema(@Nullable SimpleFeatureType targetSchema); FeatureReaderBuilder screenMapReplaceGeometryWithPx(Boolean replace); FeatureReaderBuilder retypeIfNeeded(boolean retype); static AutoCloseableIterator<NodeRef> toFeatureRefs(
            final AutoCloseableIterator<DiffEntry> diffs, final ChangeType changeType);  }### Answer:
@Test public void testHeadRef() throws Exception { String branchName = "mybranch"; branch(branchName); checkout(branchName); assertTrue(delete(points1)); add(); commit("deleted points1"); checkout("master"); builder.headRef(branchName); verifyFeatures(Query.ALL, points2, points3); }