TestExecutor.ts

import { AssertionError } from "assert";
import { performance } from "perf_hooks";
import { TestResult } from "./TestResult";
import { TestResultState } from "./TestResult";
import { TestFunction } from "./TestFunction";

export class TestExecutor {
  async executeTest(
    test: TestFunction,
    timeoutMs: number
  ): Promise<TestResult> {
    let t0;

    try {
      t0 = performance.now();

      const testTimeout = new Promise((_, reject) => {
        const id = setTimeout(() => {
          clearTimeout(id);
          reject(`Test timed out after ${timeoutMs}ms`);
        }, timeoutMs);
      });

      await Promise.race([test.apply(null), testTimeout]);

      const t1 = performance.now();
      const time = t1 - t0;

      return {
        state: TestResultState.PASS,
        time,
      };
    } catch (e) {
      const t1 = performance.now();
      const time = t1 - (t0 as number);

      const isAssertionError = e instanceof AssertionError;

      const state = isAssertionError
        ? TestResultState.FAIL
        : TestResultState.ERROR;

      const result: TestResult = {
        state,
        time,
        message: e.message,
      };

      if (!isAssertionError) {
        result.error = e;
      }

      return result;
    }
  }
}