test(e2e): add test for jest-ts usecase (#2177)

e2e/helpers.ts

@@ -43,9 +43,15 @@ export async function expectMetricsResult(expectedMetricsResult: Partial<Metrics
 
 export async function expectMetrics(expectedMetrics: Partial<Metrics>) {
   const actualMetricsResult = await readMutationTestResult();
+  const actualMetrics: Partial<Metrics> = {};
   Object.entries(expectedMetrics).forEach(([key, value]) => {
-    expect(actualMetricsResult.metrics).property(key, value);
+    if (key === 'mutationScore' || key === 'mutationScoreBasedOnCoveredCode') {
+      actualMetrics[key] = parseFloat(actualMetricsResult.metrics[key].toFixed(2));
+    } else {
+      actualMetrics[key as keyof Metrics] = value;
+    }
   });
+  expect(actualMetrics).deep.eq(expectedMetrics);
 }
 
 export function produceMetrics(metrics: Partial<Metrics>): Metrics {

e2e/package.json

@@ -27,6 +27,7 @@
     "mutation-testing-metrics": "~1.3.0",
     "rxjs": "~6.5.3",
     "semver": "~6.3.0",
+    "ts-jest": "^25.4.0",
     "ts-node": "~7.0.0",
     "typescript": "~3.7.2",
     "webpack": "~4.41.2"

e2e/test/jest-with-ts/jest.config.js

@@ -0,0 +1,10 @@
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+
+  // Example pulled from: https://kulshekhar.github.io/ts-jest/user/config/#example
+  moduleNameMapper: {
+    '^@App/(.*)$': '<rootDir>/src/$1',
+    '^lib/(.*)$': '<rootDir>/common/$1'
+  }
+};