test/langtools/tools/javac/generics/bridges/VerifyNoBridgeLoopTest.java

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 * 2 along with this work; if not, write to the Free Software Foundation,
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/*
 * @test
 * @bug 8189659
 * @summary Verify that the infinite loop of bridges from JDK-6996415 is not reintroduced
 * @run main VerifyNoBridgeLoopTest
 */

public class VerifyNoBridgeLoopTest {
    static class Expression {}
    abstract static class ExpVisitor<R,D> {
      static int f = 1;
      protected R visitExpression (Expression exp, D d) { f *= 100; System.out.println(exp); return null; }
    }

    abstract static class ExpExpVisitor<D> extends ExpVisitor<Expression,D> { }

    static class FindTail extends ExpExpVisitor<Expression> {
      protected Expression visitExpression (Expression exp, Expression returnContinuation) {
          return super.visitExpression(exp, exp);
      }
    }
    public static void main(String [] args) {
        new FindTail().visitExpression(new Expression(), new Expression());
        ExpVisitor<Expression, Expression> e = new FindTail();
        e.visitExpression(new Expression(), new Expression());
        if (e.f != 10000)
            throw new AssertionError("Incorrect call sequence");
    }
}