Function it

testing/bdd.ts:566–643

(...args: ItArgs<T>)

 * @param args The test case
 */
export function it<T>(...args: ItArgs<T>) {
  if (TestSuiteInternal.runningCount > 0) {
    throw new Error(
      "Cannot register new test cases after already registered test cases start running",
    );
  }
  const assertionState = getAssertionState();
  const options = itDefinition(...args);
  const { suite } = options;
  const testSuite = suite
    ? TestSuiteInternal.suites.get(suite.symbol)
    : TestSuiteInternal.current;

  if (!TestSuiteInternal.started) TestSuiteInternal.started = true;
  if (testSuite) {
    TestSuiteInternal.addStep(testSuite, options);
  } else {
    const {
      name,
      fn,
      ignore,
      only,
      permissions,
      sanitizeExit = globalSanitizersState.sanitizeExit,
      sanitizeOps = globalSanitizersState.sanitizeOps,
      sanitizeResources = globalSanitizersState.sanitizeResources,
    } = options;
    const opts: Deno.TestDefinition = {
      name,
      async fn(t) {
        TestSuiteInternal.runningCount++;
        try {
          await fn.call({} as T, t);
        } finally {
          TestSuiteInternal.runningCount--;
        }

        try {
          if (assertionState.checkAssertionErrorState()) {
            throw new AssertionError(
              "Expected at least one assertion to be called but received none",
            );
          }

          if (assertionState.checkAssertionCountSatisfied()) {
            throw new AssertionError(
              `Expected exactly ${assertionState.assertionCount} ${
                assertionState.assertionCount === 1 ? "assertion" : "assertions"
              } to be called, ` +
                `but received ${assertionState.assertionTriggeredCount}`,
            );
          }
        } finally {
          assertionState.resetAssertionState();
        }
      },
    };
    if (ignore !== undefined) {