Custom reporter integration

.vscode/settings.json

@@ -2,5 +2,7 @@
   "jest.pathToJest": "npm run jest --",
   "editor.rulers": [
     80
-  ]
+],
+"eslint.enable": true,
+"javascript.validate.enable": false
 }

packages/jest-cli/src/TestRunner.js

@@ -379,11 +379,16 @@ class TestRunner {
   _setupReporters() {
     const config = this._config;
 
-    this.addReporter(
-      config.verbose
-        ? new VerboseReporter(config)
-        : new DefaultReporter(),
-    );
+    if (config.reporters) {
+      this._addCustomReporters(config.reporters);
+    }
+
+    // Default Reporters are setup when
+    // noDefaultReporters is false, which is false by default
+    // and can be set to true in configuration.
+    if (!config.noDefaultReporters) {
+      this._setupDefaultReporters();
+    }
 
     if (config.collectCoverage) {
       // coverage reporter dependency graph is pretty big and we don't
@@ -392,12 +397,74 @@ class TestRunner {
       this.addReporter(new CoverageReporter());
     }
 
-    this.addReporter(new SummaryReporter());
     if (config.notify) {
       this.addReporter(new NotifyReporter(this._startRun));
     }
   }
 
+  /**
+   * _setupDefaultReporters
+   * Method for setting up the default reporters
+   */
+  _setupDefaultReporters() {
+    const config = this._config;
+
+    this.addReporter(
+      config.verbose
+        ? new VerboseReporter(config)
+        : new DefaultReporter()
+    );
+
+    this.addReporter(new SummaryReporter());
+  }
+
+  /**
+   * Add Custom reporters to Jest
+   * Custom reporters can be added to Jest using the reporters option in Jest
+   * Config. The format for adding a custom reporter is following
+   *
+   * "reporters": [
+   *    ["reporterPath/packageName", { option1: 'fasklj' }], 
+   *    // Format if we want to specify options
+   *    
+   *    "reporterName"
+   *    // Format if we don't want to specify any options
+   * ]
+   */
+  _addCustomReporters(reporters: any) {
+    let reporterPath, reporterConfig;
+
+    reporters.forEach(entry => {
+      if (Array.isArray(entry)) {
+        [reporterPath, reporterConfig] = entry;
+      } else {
+        if (typeof entry !== 'string') {
+          throw new Error(`
+            Unexpected custom reporter configuration.
+            Expected to get either a path string or an array of [path, confg]
+            got: ${JSON.stringify(entry)}
+          `);
+        }
+
+        reporterPath = entry;
+      }
+
+      try {
+        const reporter = require(reporterPath);
+        this.addReporter(new reporter(reporterConfig || {}));
+      } catch (error) {
+        console.error(`
+          Failed to set up reporter:
+            ${JSON.stringify(reporterPath)}
+          Config:
+            ${JSON.stringify(reporterConfig)}
+        `);
+
+        throw error;
+      }
+    });
+  }
+
   _bailIfNeeded(aggregatedResults: AggregatedResult, watcher: TestWatcher) {
     if (this._config.bail && aggregatedResults.numFailedTests !== 0) {
       if (watcher.isWatchMode()) {

packages/jest-cli/src/__tests__/TestRunner-test.js

@@ -38,6 +38,100 @@ test('.addReporter() .removeReporter()', () => {
   expect(runner._dispatcher._reporters).not.toContain(reporter);
 });
 
+// Checking for the method _addCustomReporters
+// Custom reporters used here are the reporters within the package
+// No extra reporters are included to be used
+describe('_addCustomReporters', () => {
+  // Paths for the given reporters
+  const SUMMARY_REPORTER_PATH = './reporters/SummaryReporter.js';
+  const VERBOSE_REPORTER_PATH = './reporters/VerboseReporter.js';
+  const DEFAULT_REPORTER_PATH = './reporters/DefaultReporter.js';
+
+  // Requiring constructors of the given reporters
+  // to check against the reporters added
+  const summaryReporter = require('.' + SUMMARY_REPORTER_PATH);
+  const verboseReporter = require('.' + VERBOSE_REPORTER_PATH);
+  const defaultReporter = require('.' + DEFAULT_REPORTER_PATH);
+
+  let runner;
+
+  beforeEach(() => {
+    runner = new TestRunner({}, {}, {});
+
+    // Removing all the reporters we previously have in the 
+    // Dispatcher. Helps in removing inconsistencies in Tests.
+    runner._dispatcher._reporters = [];
+  });
+
+  test('adds reporter using 2D Array format', () => {
+    const reporters = [
+      [SUMMARY_REPORTER_PATH, {}],
+    ];
+
+    expect(runner._dispatcher._reporters).toHaveLength(0);
+    expect(runner._dispatcher._reporters[0]).toBeUndefined();
+
+    runner._addCustomReporters(reporters);
+
+    expect(runner._dispatcher._reporters).toHaveLength(1);
+    expect(runner._dispatcher._reporters.pop()).toBeInstanceOf(summaryReporter);
+  });
+
+  test('adds reporter using 2D syntax with no configuration object', () => {
+    const reporters = [
+      [SUMMARY_REPORTER_PATH],
+    ];
+
+    runner._addCustomReporters(reporters);
+
+    expect(runner._dispatcher._reporters).toHaveLength(1);
+    expect(runner._dispatcher._reporters.pop()).toBeInstanceOf(SummaryReporter);
+  });
+
+  test('adds reporter using string syntax (no custom configuration)', () => {
+    const reporters = [
+      SUMMARY_REPORTER_PATH,
+    ];
+
+    runner._addCustomReporters(reporters);
+
+    expect(runner._dispatcher._reporters).toHaveLength(1);
+    expect(runner._dispatcher._reporters.pop()).toBeInstanceOf(summaryReporter);
+  });
+
+  test('adds two reporters with variable format', () => {
+    const reporters = [
+      VERBOSE_REPORTER_PATH,
+      [DEFAULT_REPORTER_PATH, {}],
+    ];
+    runner._addCustomReporters(reporters);
+
+    expect(runner._dispatcher._reporters).toHaveLength(2);
+
+    expect(runner._dispatcher._reporters[0]).toBeInstanceOf(verboseReporter);
+    expect(runner._dispatcher._reporters[1]).toBeInstanceOf(defaultReporter);
+  });
+
+  test('throws on invalid file path', () => {
+    const reporters = [
+      ['ohthisisnotgoingtobearealpath.sadfslj', {}],
+    ];
+
+    const addInvalidReporters = () => {
+      runner._addCustomReporters(reporters);    
+    };
+
+    expect(addInvalidReporters).toThrow();
+    expect(addInvalidReporters).toThrow(/Cannot find module/);
+    expect(runner._dispatcher._reporters).toHaveLength(0);
+  });
+
+  test('throws on invalid argument to reporter', () => {
+    expect(() => {
+      runner._addCustomReporters('This should be an array obviously');
+    }).toThrow();
+  });
+});
 
 describe('_createInBandTestRun()', () => {
   test('injects the rawModuleMap to each the worker in watch mode', () => {

packages/jest-config/src/normalize.js

@@ -349,11 +349,15 @@ function normalize(config: InitialConfig, argv: Object = {}) {
       case 'moduleLoader':
       case 'modulePaths':
       case 'name':
+      case 'noDefaultReporters':
       case 'noStackTrace':
       case 'notify':
       case 'persistModuleRegistryBetweenSpecs':
       case 'preset':
       case 'replname':
+      case 'reporters':
+        value = _replaceRootDirTags(config.rootDir, config[key]);
+        break;
       case 'resetMocks':
       case 'resetModules':
       case 'rootDir':

packages/jest-config/src/validConfig.js

@@ -54,9 +54,13 @@ module.exports = ({
   modulePathIgnorePatterns: ['<rootDir>/build/'],
   modulePaths: ['/shared/vendor/modules'],
   name: 'string',
+  noDefaultReporters: false,
   noStackTrace: false,
   notify: false,
   preset: 'react-native',
+  reporters: [
+    ['./here-it-goes.js', {option1: true}],
+  ],
   resetMocks: false,
   resetModules: false,
   rootDir: '/',

types/Config.js

@@ -84,9 +84,11 @@ export type Config = {|
   modulePathIgnorePatterns: Array<string>,
   modulePaths: Array<string>,
   name: string,
+  noDefaultReporters: boolean,
   noStackTrace: boolean,
   notify: boolean,
   preset: ?string,
+  reporters: Array<string | Array<string | Object>>,
   resetMocks: boolean,
   resetModules: boolean,
   rootDir: Path,
@@ -132,6 +134,7 @@ export type InitialConfig = {|
   forceExit?: boolean,
   globals?: ConfigGlobals,
   haste?: HasteConfig,
+  reporters?: Array<string | Array<string | Object>>,
   logHeapUsage?: boolean,
   logTransformErrors?: ?boolean,
   moduleDirectories?: Array<string>,
@@ -142,6 +145,7 @@ export type InitialConfig = {|
   modulePathIgnorePatterns?: Array<string>,
   modulePaths?: Array<string>,
   name?: string,
+  noDefaultReporters?: boolean,
   noStackTrace?: boolean,
   notify?: boolean,
   preprocessorIgnorePatterns?: Array<Glob>,