1 /*
 2  * Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved.
 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 4  *
 5  * This code is free software; you can redistribute it and/or modify it
 6  * under the terms of the GNU General Public License version 2 only, as
 7  * published by the Free Software Foundation.
 8  *
 9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 
24 /*
25  * @test
26  * @modules jdk.incubator.code
27  * @run junit TestMethodRefLambda
28  */
29 
30 import jdk.incubator.code.Reflect;
31 import jdk.incubator.code.Op;
32 import jdk.incubator.code.Quoted;
33 import jdk.incubator.code.dialect.java.JavaOp;
34 import org.junit.jupiter.api.Assertions;
35 import org.junit.jupiter.api.TestInstance;
36 import org.junit.jupiter.params.ParameterizedTest;
37 import org.junit.jupiter.params.provider.MethodSource;
38 
39 import java.util.List;
40 import java.util.function.BiFunction;
41 import java.util.function.Function;
42 import java.util.function.IntUnaryOperator;
43 
44 // Declare a per-class lifecycle, so we can declare an instance factory method
45 // as the source of arguments for parameterized tests
46 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
47 public class TestMethodRefLambda {
48 
49     @Reflect
50     List<Object> methodRefLambdas() {
51         return List.of(
52                 (IntUnaryOperator) TestMethodRefLambda::m1,
53                 (IntUnaryOperator) TestMethodRefLambda::m2,
54                 (Function<Integer, Integer>) TestMethodRefLambda::m1,
55                 (Function<Integer, Integer>) TestMethodRefLambda::m2,
56                 (IntUnaryOperator) this::m3,
57                 (BiFunction<TestMethodRefLambda, Integer, Integer>) TestMethodRefLambda::m4
58         );
59     }
60 
61     @ParameterizedTest
62     @MethodSource("methodRefLambdas")
63     public void testIsMethodReference(Object q) {
64         Quoted quoted = Op.ofQuotable(q).get();
65         JavaOp.LambdaOp lop = (JavaOp.LambdaOp) quoted.op();
66         Assertions.assertTrue(lop.methodReference().isPresent());
67     }
68 
69     static int m1(int i) {
70         return i;
71     }
72 
73     static Integer m2(Integer i) {
74         return i;
75     }
76 
77     int m3(int i) {
78         return i;
79     }
80 
81     static int m4(TestMethodRefLambda tl, int i) {
82         return i;
83     }
84 }