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/*
* Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 8024415
* @summary Pretty printing of JCConditional does not follow the precedence and
* associativity rules of JCConditional
* @modules jdk.compiler/com.sun.tools.javac.file
* jdk.compiler/com.sun.tools.javac.tree
* jdk.compiler/com.sun.tools.javac.util
* @run testng T8024415
*/
import static org.testng.Assert.assertEquals;
import java.io.IOException;
import java.io.StringWriter;
import org.testng.annotations.Test;
import com.sun.tools.javac.file.JavacFileManager;
import com.sun.tools.javac.tree.JCTree;
import com.sun.tools.javac.tree.JCTree.JCExpression;
import com.sun.tools.javac.tree.Pretty;
import com.sun.tools.javac.tree.TreeMaker;
import com.sun.tools.javac.util.Context;
import com.sun.tools.javac.util.Names;
/*
* Test verifies that the precedence rules of conditional expressions
* (JCConditional) are correct.
*/
@Test
public class T8024415 {
TreeMaker maker;
JCExpression x;
public T8024415() {
Context ctx = new Context();
JavacFileManager.preRegister(ctx);
maker = TreeMaker.instance(ctx);
Names names = Names.instance(ctx);
x = maker.Ident(names.fromString("x"));
}
// JLS 15.25: The conditional operator is syntactically right-associative
// (it groups right-to-left). Thus, a?b:c?d:e?f:g means the same as
// a?b:(c?d:(e?f:g)).
public void testAssociativity() throws IOException {
JCTree left = maker.Conditional(maker.Conditional(x, x, x), x, x);
JCTree right = maker.Conditional(x, x, maker.Conditional(x, x, x));
String prettyLeft = prettyPrint(left);
String prettyRight = prettyPrint(right);
assertEquals(prettyLeft.replaceAll("\\s", ""), "(x?x:x)?x:x");
assertEquals(prettyRight.replaceAll("\\s", ""), "x?x:x?x:x");
}
// The true-part of of a conditional expression is surrounded by ? and :
// and can thus always be parsed unambiguously without surrounding
// parentheses.
public void testPrecedence() throws IOException {
JCTree left = maker.Conditional(maker.Assign(x, x), x, x);
JCTree middle = maker.Conditional(x, maker.Assign(x, x), x);
JCTree right = maker.Conditional(x, x, maker.Assign(x, x));
String prettyLeft = prettyPrint(left);
String prettyMiddle = prettyPrint(middle);
String prettyRight = prettyPrint(right);
assertEquals(prettyLeft.replaceAll("\\s", ""), "(x=x)?x:x");
assertEquals(prettyMiddle.replaceAll("\\s", ""), "x?x=x:x");
assertEquals(prettyRight.replaceAll("\\s", ""), "x?x:(x=x)");
}
// Helper method
private static String prettyPrint(JCTree tree) throws IOException {
StringWriter sw = new StringWriter();
new Pretty(sw, true).printExpr(tree);
return sw.toString();
}
}
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