Function then

packages/react/src/ReactAct.js:135–178

(resolve: T => mixed, reject: mixed => mixed)

      return {
        then(resolve: T => mixed, reject: mixed => mixed) {
          didAwaitActCall = true;
          thenable.then(
            returnValue => {
              popActScope(prevActQueue, prevActScopeDepth);
              if (prevActScopeDepth === 0) {
                class="cm">// We're exiting the outermost `act` scope. Flush the queue.
                try {
                  flushActQueue(queue);
                  queueMacrotask(() =>
                    class="cm">// Recursively flush tasks scheduled by a microtask.
                    recursivelyFlushAsyncActWork(returnValue, resolve, reject),
                  );
                } catch (error) {
                  class="cm">// `thenable` might not be a real promise, and `flushActQueue`
                  class="cm">// might throw, so we need to wrap `flushActQueue` in a
                  class="cm">// try/catch.
                  ReactSharedInternals.thrownErrors.push(error);
                }
                if (ReactSharedInternals.thrownErrors.length > 0) {
                  const thrownError = aggregateErrors(
                    ReactSharedInternals.thrownErrors,
                  );
                  ReactSharedInternals.thrownErrors.length = 0;
                  reject(thrownError);
                }
              } else {
                resolve(returnValue);
              }
            },
            error => {
              popActScope(prevActQueue, prevActScopeDepth);
              if (ReactSharedInternals.thrownErrors.length > 0) {
                const thrownError = aggregateErrors(
                  ReactSharedInternals.thrownErrors,
                );
                ReactSharedInternals.thrownErrors.length = 0;
                reject(thrownError);
              } else {
                reject(error);
              }
            },
          );
        },
      };
    } else {
      const returnValue: T = (result: any);