System.Threading.Tests.ReaderWriterLockTests.DowngradeQuirks_ChangedInDotNetCore C# (CSharp) Method

        public static void DowngradeQuirks_ChangedInDotNetCore()
        {
            var trwl = new TestReaderWriterLock();
            TestLockCookie tlc;

            // Downgrade quirk when downgrading from a state where multiple recursive write locks are held, when the lock cookie
            // was obtained from a state where:
            //   - No lock was held
            //   - When any number of recursive write locks are held
            // The expectation in both cases is that a downgrade respects the lock cookie and restores the write lock recursion
            // level to the point indicated by the lock cookie.
            {
                // Lock cookie obtained when no lock is held
                tlc = trwl.UpgradeToWriterLock();
                trwl.AcquireWriterLock();
                trwl.DowngradeFromWriterLock(tlc);
                trwl.VerifyIsReaderLockHeld(false);
                trwl.VerifyIsWriterLockHeld(false);

                // Lock cookie obtained when write locks are held
                trwl.AcquireWriterLock();
                tlc = trwl.UpgradeToWriterLock();
                trwl.AcquireWriterLock();
                trwl.DowngradeFromWriterLock(tlc);
                trwl.VerifyIsReaderLockHeld(false);
                trwl.VerifyIsWriterLockHeld(true);
                trwl.ReleaseWriterLock();
                trwl.VerifyIsWriterLockHeld(false);
            }

            // Cannot downgrade to a recursive write lock level greater than or equal to the current
            trwl.AcquireWriterLock();
            trwl.AcquireWriterLock();
            tlc = trwl.UpgradeToWriterLock();
            trwl.ReleaseWriterLock();
            trwl.DowngradeFromWriterLock(tlc, InvalidLockCookieExceptionHResult);
            trwl.ReleaseWriterLock();
            trwl.DowngradeFromWriterLock(tlc, InvalidLockCookieExceptionHResult);
            trwl.ReleaseWriterLock();
            trwl.VerifyIsReaderLockHeld(false);
            trwl.VerifyIsWriterLockHeld(false);

            trwl.Dispose();
        }