Fri, 24 Apr 2020 03:58:51 +0100
Merge
1 /*
2 * Copyright (c) 2013, 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 */
24 /*
25 * @test
26 * @bug 8024415
27 * @summary Pretty printing of JCConditional does not follow the precedence and
28 * associativity rules of JCConditional
29 * @run testng T8024415
30 */
33 import static org.testng.Assert.assertEquals;
35 import java.io.IOException;
36 import java.io.StringWriter;
38 import org.testng.annotations.Test;
40 import com.sun.tools.javac.file.JavacFileManager;
41 import com.sun.tools.javac.tree.JCTree;
42 import com.sun.tools.javac.tree.JCTree.JCExpression;
43 import com.sun.tools.javac.tree.Pretty;
44 import com.sun.tools.javac.tree.TreeMaker;
45 import com.sun.tools.javac.util.Context;
46 import com.sun.tools.javac.util.Names;
49 /*
50 * Test verifies that the precedence rules of conditional expressions
51 * (JCConditional) are correct.
52 */
53 @Test
54 public class T8024415 {
56 TreeMaker maker;
57 JCExpression x;
60 public T8024415() {
61 Context ctx = new Context();
62 JavacFileManager.preRegister(ctx);
63 maker = TreeMaker.instance(ctx);
64 Names names = Names.instance(ctx);
65 x = maker.Ident(names.fromString("x"));
66 }
69 // JLS 15.25: The conditional operator is syntactically right-associative
70 // (it groups right-to-left). Thus, a?b:c?d:e?f:g means the same as
71 // a?b:(c?d:(e?f:g)).
72 public void testAssociativity() throws IOException {
74 JCTree left = maker.Conditional(maker.Conditional(x, x, x), x, x);
75 JCTree right = maker.Conditional(x, x, maker.Conditional(x, x, x));
77 String prettyLeft = prettyPrint(left);
78 String prettyRight = prettyPrint(right);
80 assertEquals(prettyLeft.replaceAll("\\s", ""), "(x?x:x)?x:x");
81 assertEquals(prettyRight.replaceAll("\\s", ""), "x?x:x?x:x");
83 }
86 // The true-part of of a conditional expression is surrounded by ? and :
87 // and can thus always be parsed unambiguously without surrounding
88 // parentheses.
89 public void testPrecedence() throws IOException {
91 JCTree left = maker.Conditional(maker.Assign(x, x), x, x);
92 JCTree middle = maker.Conditional(x, maker.Assign(x, x), x);
93 JCTree right = maker.Conditional(x, x, maker.Assign(x, x));
95 String prettyLeft = prettyPrint(left);
96 String prettyMiddle = prettyPrint(middle);
97 String prettyRight = prettyPrint(right);
99 assertEquals(prettyLeft.replaceAll("\\s", ""), "(x=x)?x:x");
100 assertEquals(prettyMiddle.replaceAll("\\s", ""), "x?x=x:x");
101 assertEquals(prettyRight.replaceAll("\\s", ""), "x?x:(x=x)");
103 }
106 // Helper method
107 private static String prettyPrint(JCTree tree) throws IOException {
108 StringWriter sw = new StringWriter();
109 new Pretty(sw, true).printExpr(tree);
110 return sw.toString();
111 }
113 }