TreeUtils { public static boolean isBooleanLiteral(Tree tree) { if (tree.is(Kind.NAME)) { String name = ((Name) tree).name(); return name.equals("True") || name.equals("False"); } return false; } private  TreeUtils(); @CheckForNull static Tree firstAncestor(Tree tree, Predicate<Tree> predicate); @CheckForNull static Tree firstAncestorOfKind(Tree tree, Kind... kinds); static List<Token> tokens(Tree tree); static List<Token> nonWhitespaceTokens(Tree tree); static boolean hasDescendant(Tree tree, Predicate<Tree> predicate); static Stream<Expression> flattenTuples(Expression expression); static Optional<Symbol> getSymbolFromTree(@Nullable Tree tree); @CheckForNull static ClassSymbol getClassSymbolFromDef(@Nullable ClassDef classDef); @CheckForNull static FunctionSymbol getFunctionSymbolFromDef(@Nullable FunctionDef functionDef); static List<Parameter> nonTupleParameters(FunctionDef functionDef); static List<Parameter> positionalParameters(FunctionDef functionDef); static List<FunctionDef> topLevelFunctionDefs(ClassDef classDef); @CheckForNull static RegularArgument argumentByKeyword(String keyword, List<Argument> arguments); @CheckForNull static RegularArgument nthArgumentOrKeyword(int argPosition, String keyword, List<Argument> arguments); static boolean isBooleanLiteral(Tree tree); static String nameFromExpression(Expression expression); @CheckForNull static LocationInFile locationInFile(Tree tree, @Nullable String fileId);  }
@Test public void test_isBooleanLiteral() { assertThat(TreeUtils.isBooleanLiteral(lastExpression("True"))).isTrue(); assertThat(TreeUtils.isBooleanLiteral(lastExpression("False"))).isTrue(); assertThat(TreeUtils.isBooleanLiteral(lastExpression("x"))).isFalse(); assertThat(TreeUtils.isBooleanLiteral(lastExpression("foo()"))).isFalse(); }