AbsTests.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * version 2 for more details (a copy is included in the LICENSE file that
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 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 */

import java.util.function.*;

/*
 * @test
 * @bug 8241374
 * @summary Test abs and absExact for Math and StrictMath
 */
public class AbsTests {
    private static int errors = 0;

    public static void main(String... args) {
        errors += testInRangeIntAbs();
        errors += testIntMinValue();
        errors += testInRangeLongAbs();
        errors += testLongMinValue();

        if (errors > 0) {
            throw new RuntimeException(errors + " errors found testing abs.");
        }
    }

    private static int testInRangeIntAbs() {
        int errors = 0;
        int[][] testCases  = {
            // Argument to abs, expected result
            {+0, 0},
            {+1, 1},
            {-1, 1},
            {-2, 2},
            {+2, 2},
            {-Integer.MAX_VALUE, Integer.MAX_VALUE},
            {+Integer.MAX_VALUE, Integer.MAX_VALUE}
        };

        for(var testCase : testCases) {
            errors += testIntAbs(Math::abs,      testCase[0], testCase[1]);
            errors += testIntAbs(Math::absExact, testCase[0], testCase[1]);
        }
        return errors;
    }

    private static int testIntMinValue() {
        int errors = 0;
        // Strange but true
        errors += testIntAbs(Math::abs, Integer.MIN_VALUE, Integer.MIN_VALUE);

        // Test exceptional behavior for absExact
        try {
            int result = Math.absExact(Integer.MIN_VALUE);
            System.err.printf("Bad return value %d from Math.absExact(MIN_VALUE)%n",
                              result);
            errors++;
        } catch (ArithmeticException ae) {
            ; // Expected
        }
        return errors;
    }

    private static int testIntAbs(IntUnaryOperator absFunc,
                           int argument, int expected) {
        int result = absFunc.applyAsInt(argument);
        if (result != expected) {
            System.err.printf("Unexpected int abs result %d for argument %d%n",
                                result, argument);
            return 1;
        } else {
            return 0;
        }
    }

    // --------------------------------------------------------------------

    private static long testInRangeLongAbs() {
        int errors = 0;
        long[][] testCases  = {
            // Argument to abs, expected result
            {+0L, 0L},
            {+1L, 1L},
            {-1L, 1L},
            {-2L, 2L},
            {+2L, 2L},
            {-Integer.MAX_VALUE, Integer.MAX_VALUE},
            {+Integer.MAX_VALUE, Integer.MAX_VALUE},
            { Integer.MIN_VALUE, -((long)Integer.MIN_VALUE)},
            {-Long.MAX_VALUE, Long.MAX_VALUE},
        };

        for(var testCase : testCases) {
            errors += testLongAbs(Math::abs,      testCase[0], testCase[1]);
            errors += testLongAbs(Math::absExact, testCase[0], testCase[1]);
        }
        return errors;
    }

    private static int testLongMinValue() {
        int errors = 0;
        // Strange but true
        errors += testLongAbs(Math::abs, Long.MIN_VALUE, Long.MIN_VALUE);

        // Test exceptional behavior for absExact
        try {
            long result = Math.absExact(Long.MIN_VALUE);
            System.err.printf("Bad return value %d from Math.absExact(MIN_VALUE)%n",
                              result);
            errors++;
        } catch (ArithmeticException ae) {
            ; // Expected
        }
        return errors;
    }

    private static int testLongAbs(LongUnaryOperator absFunc,
                           long argument, long expected) {
        long result = absFunc.applyAsLong(argument);
        if (result != expected) {
            System.err.printf("Unexpected long abs result %d for argument %d%n",
                                result, argument);
            return 1;
        } else {
            return 0;
        }
    }
}