@CollectionSize.Require(ZERO)
  public void testPeek_empty() {
    assertNull("emptyQueue.peek() should return null", getQueue().peek());
    expectUnchanged();
  }

  @CollectionSize.Require(ONE)
  public void testPeek_size1() {
    assertEquals("size1Queue.peek() should return first element", e0(), getQueue().peek());
    expectUnchanged();
  }

  @CollectionFeature.Require(KNOWN_ORDER)

  return object : mockwebserver3.Dispatcher() {
    override fun dispatch(request: mockwebserver3.RecordedRequest): mockwebserver3.MockResponse = delegate.dispatch(request.unwrap()).wrap()

    override fun peek(): mockwebserver3.MockResponse = delegate.peek().wrap()

    override fun close() {
      delegate.shutdown()
    }
  }
}

internal fun MockResponse.wrap(): mockwebserver3.MockResponse {

    // other threads waiting on take() will also return.
    if (result == DEAD_LETTER) responseQueue.add(DEAD_LETTER)

    return result
  }

  public override fun peek(): MockResponse = responseQueue.peek() ?: failFastResponse ?: super.peek()

  public open fun enqueue(response: MockResponse) {
    responseQueue.add(response)
  }

  public open fun clear() {
    responseQueue.clear()
  }

    public boolean remove(Object object) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.remove(object);
    }

    @Override
    public @Nullable E peek() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.peek();
    }

    @Override
    public E element() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.element();
    }

    @Override

        Smb2IoctlResponse ioResp = mock(Smb2IoctlResponse.class);
        SrvPipePeekResponse peek = mock(SrvPipePeekResponse.class);
        when(peek.getReadDataAvailable()).thenReturn(7);
        when(ioResp.getOutputData()).thenReturn(peek);

        when(tree.send(any(Smb2IoctlRequest.class), eq(RequestParam.NO_RETRY))).thenReturn(ioResp);

        // Act

 * an HTTP call to a remote server.
 */
interface TrailersSource {
  @Throws(IOException::class)
  fun peek(): Headers? = null

  @Throws(IOException::class)
  fun get(): Headers

  companion object {
    @JvmField
    val EMPTY: TrailersSource =
      object : TrailersSource {
        override fun peek() = Headers.EMPTY

        override fun get() = Headers.EMPTY
      }
  }

		t.Fatalf("length differs from expected")
	}

	v, ok := lc.Peek("key1")
	if v != "val1" {
		t.Fatalf("value differs from expected")
	}
	if !ok {
		t.Fatalf("should be true")
	}

	if !lc.Contains("key1") {
		t.Fatalf("should contain key1")
	}
	if lc.Contains("key2") {
		t.Fatalf("should not contain key2")
	}

	v, ok = lc.Peek("key2")
	if v != "" {
		t.Fatalf("should be empty")
	}

        SrvPipePeekResponse peek = resp.getOutputData(SrvPipePeekResponse.class);
        assertNotNull(peek);
        assertEquals(16, resp.getOutputLength());
        // Default zeros
        assertEquals(0, peek.getNamedPipeState());
        assertEquals(0, peek.getReadDataAvailable());
        assertEquals(0, peek.getNumberOfMessages());
        assertEquals(0, peek.getMessageLength());
    }

	switch t.tok {
	case '\n':
		t.line++
	case '-':
		if s.Peek() == '>' {
			s.Next()
			t.tok = ARR
			return ARR
		}
	case '@':
		if s.Peek() == '>' {
			s.Next()
			t.tok = ROT
			return ROT
		}
	case '<':
		if s.Peek() == '<' {
			s.Next()
			t.tok = LSH
			return LSH
		}
	case '>':
		if s.Peek() == '>' {
			s.Next()
			t.tok = RSH
			return RSH
		}
	}

}

func (in *Input) expectNewline(directive string) {
	tok := in.Stack.Next()
	if tok != '\n' {
		in.expectText("expected newline after", directive)
	}
}

func (in *Input) Next() ScanToken {
	if in.peek {
		in.peek = false
		tok := in.peekToken
		in.text = in.peekText
		return tok
	}
	// If we cannot generate a token after 100 macro invocations, we're in trouble.
	// The usual case is caught by Push, below, but be safe.