feat: Added GithubActionsReporter

packages/jest-reporters/src/GithubActionsReporter.ts

@@ -0,0 +1,47 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import type {
+  AggregatedResult, TestResult
+} from '@jest/test-result';
+import BaseReporter from './BaseReporter';
+import type { Context } from './types';
+
+const newLine = /\n/g;
+const encodedNewLine = "%0A";
+const lineAndColumnInStackTrace = /^.*:([0-9]+):([0-9]+).*$/;
+
+export default class GithubActionReporter extends BaseReporter {
+  onRunComplete(
+    _contexts?: Set<Context>,
+    aggregatedResults?: AggregatedResult) {
+    var messages = getMessages(aggregatedResults?.testResults);
+
+    for (const message of messages) {
+      console.log(message);
+    }
+  }
+}
+
+function getMessages(results: TestResult[] | undefined){
+  if(!results) return [];
+
+  return results
+    .reduce(flatMap(({ testFilePath, testResults }) => testResults
+      .filter(r => r.status === "failed")
+      .reduce(flatMap(r => r.failureMessages), [])
+      .map(m => m.replace(newLine, encodedNewLine))
+      .map(m => lineAndColumnInStackTrace.exec(m))
+      .filter((m): m is RegExpExecArray => m !== null)
+      .map(([message, line, col]) =>
+        `::error file=${testFilePath},line=${line},col=${col}::${message}`)),
+    []);
+}
+
+function flatMap<In, Out>(map: (x: In) => Out[]) {
+  return (out: Out[], entry: In) => out.concat(...map(entry))
+}

packages/jest-reporters/src/index.ts

@@ -24,6 +24,7 @@ export {default as DefaultReporter} from './DefaultReporter';
 export {default as NotifyReporter} from './NotifyReporter';
 export {default as SummaryReporter} from './SummaryReporter';
 export {default as VerboseReporter} from './VerboseReporter';
+export {default as GithubActionsReporter} from './GithubActionsReporter';
 export type {
   Context,
   Reporter,