*/
  @SuppressWarnings("unchecked")
  public static <T extends @Nullable Object> Collector<T, ?, T> onlyElement() {
    return (Collector) ONLY_ELEMENT;
  }

  /**
   * This atrocity is here to let us report several of the elements in the stream if there were more
   * than one, not just two.
   */
  private static final class ToOptionalState {
    static final int MAX_EXTRAS = 4;

    @CheckForNull Object element;

                  CollectionFeature.RESTRICTS_ELEMENTS,
                  ListFeature.SUPPORTS_SET)
              .createTestSuite());
    }
    return suite;
  }

  // Test generators.  To let the GWT test suite generator access them, they need to be
  // public named classes with a public default constructor.

  public static final class BytesAsListGenerator extends TestByteListGenerator {
    @Override

                  CollectionFeature.RESTRICTS_ELEMENTS,
                  ListFeature.SUPPORTS_SET)
              .createTestSuite());
    }
    return suite;
  }

  // Test generators.  To let the GWT test suite generator access them, they need to be
  // public named classes with a public default constructor.

  public static final class LongsAsListGenerator extends TestLongListGenerator {
    @Override

				//
				// Send such results anyways as this shall
				// expose a problem underneath.
				if totalPut > throughputHighestPut {
					throughputHighestResults = results
					throughputHighestPut = totalPut
					// let the client see lower value as well
					throughputHighestGet = totalGet
				}
				sendResult()
				break
			}

			// We break if we did not see 2.5% growth rate in total GET

// as an error to be reported.
func readAllInto(b []byte, r *wsutil.Reader, want int64) ([]byte, error) {
	read := int64(0)
	for {
		if len(b) == cap(b) {
			// Add more capacity (let append pick how much).
			b = append(b, 0)[:len(b)]
		}
		n, err := r.Read(b[len(b):cap(b)])
		b = b[:len(b)+n]
		if err != nil {
			if errors.Is(err, io.EOF) {
				if want >= 0 && read+int64(n) != want {

Then, the browser will send an HTTP `OPTIONS` request to the `:80`-backend, and if the backend sends the appropriate headers authorizing the communication from this different origin (`http://localhost:8080`) then the `:8080`-browser will let the JavaScript in the frontend send its request to the `:80`-backend.

To achieve this, the `:80`-backend must have a list of "allowed origins".

                else -> {
                }
            }
        }
    }

    private
    fun containsFailedTest(taskPath: String): Boolean {
        return testPathToBinaryResultsDirs[taskPath]?.let { containsFailedTest(it) } == true
    }

    private
    fun addExecutedTaskPath(taskPath: String) {

                    it.os == testCoverage.os &&
                    it.arch == testCoverage.arch &&
                    it.buildJvm == testCoverage.buildJvm
            }
            foundTestCoverage?.let {
                buildProjectClassTimes[it.asId(MASTER_CHECK_CONFIGURATION)]
            }?.also {

      "Unexpected char 0x${c.charCode()} at $i in $name value" +
        (if (isSensitiveHeader(name)) "" else ": $value")
    }
  }
}

private fun Char.charCode() =
  code.toString(16).let {
    if (it.length < 2) {
      "0$it"
    } else {
      it
    }
  }

internal fun commonHeadersOf(vararg inputNamesAndValues: String): Headers {

        ArtifactResolutionResult result = resolve(request);

        // We have collected all the problems so let's mimic the way the old code worked and just blow up right here.
        // That's right lets just let it rip right here and send a big incomprehensible blob of text at unsuspecting
        // users. Bad dog!

        resolutionErrorHandler.throwErrors(request, result);

        return result;
    }