fix(jest-types): tighten Config types and set more defaults

CHANGELOG.md

@@ -54,6 +54,7 @@
 - `[jest-snapshot]` [**BREAKING**] Remove `report` method and throw matcher errors ([#9049](https://github.com/facebook/jest/pull/9049))
 - `[jest-transform]` Properly cache transformed files across tests ([#8890](https://github.com/facebook/jest/pull/8890))
 - `[jest-transform]` Don't fail the test suite when a generated source map is invalid ([#9058](https://github.com/facebook/jest/pull/9058))
+- `[jest-types]` [**BREAKING**] Use less `null | undefined` in config types ([#9200](https://github.com/facebook/jest/pull/9200))
 - `[jest-utils]` Allow querying process.domain ([#9136](https://github.com/facebook/jest/pull/9136))
 - `[pretty-format]` Correctly detect memoized elements ([#9196](https://github.com/facebook/jest/pull/9196))
 

e2e/__tests__/__snapshots__/moduleNameMapper.test.ts.snap

@@ -19,7 +19,7 @@ FAIL __tests__/index.js
       "moduleNameMapper": {
         "/\\.(css|less)$/": "no-such-module"
       },
-      "resolver": null
+      "resolver": undefined
     }
 
        8 | 'use strict';

e2e/__tests__/__snapshots__/showConfig.test.ts.snap

@@ -13,14 +13,11 @@ exports[`--showConfig outputs config info and exits 1`] = `
         "/node_modules/"
       ],
       "cwd": "<<REPLACED_ROOT_DIR>>",
-      "dependencyExtractor": null,
       "detectLeaks": false,
       "detectOpenHandles": false,
       "errorOnDeprecated": false,
-      "filter": null,
+      "extraGlobals": [],
       "forceCoverageMatch": [],
-      "globalSetup": null,
-      "globalTeardown": null,
       "globals": {},
       "haste": {
         "computeSha1": false,
@@ -38,13 +35,12 @@ exports[`--showConfig outputs config info and exits 1`] = `
         "tsx",
         "node"
       ],
-      "moduleNameMapper": {},
+      "moduleNameMapper": [],
       "modulePathIgnorePatterns": [],
       "name": "[md5 hash]",
       "prettierPath": "prettier",
       "resetMocks": false,
       "resetModules": false,
-      "resolver": null,
       "restoreMocks": false,
       "rootDir": "<<REPLACED_ROOT_DIR>>",
       "roots": [
@@ -72,7 +68,8 @@ exports[`--showConfig outputs config info and exits 1`] = `
       "transform": [
         [
           "^.+\\\\.[jt]sx?$",
-          "<<REPLACED_JEST_PACKAGES_DIR>>/babel-jest/build/index.js"
+          "<<REPLACED_JEST_PACKAGES_DIR>>/babel-jest/build/index.js",
+          {}
         ]
       ],
       "transformIgnorePatterns": [
@@ -93,35 +90,37 @@ exports[`--showConfig outputs config info and exits 1`] = `
       "lcov",
       "clover"
     ],
-    "coverageThreshold": null,
     "detectLeaks": false,
     "detectOpenHandles": false,
     "errorOnDeprecated": false,
     "expand": false,
-    "filter": null,
-    "globalSetup": null,
-    "globalTeardown": null,
+    "extraGlobals": [],
+    "findRelatedTests": false,
+    "forceExit": false,
     "json": false,
+    "lastCommit": false,
     "listTests": false,
+    "logHeapUsage": false,
     "maxConcurrency": 5,
     "maxWorkers": "[maxWorkers]",
     "noStackTrace": false,
     "nonFlagArgs": [],
     "notify": false,
     "notifyMode": "failure-change",
+    "onlyChanged": false,
+    "onlyFailures": false,
     "passWithNoTests": false,
-    "projects": null,
+    "projects": [],
     "rootDir": "<<REPLACED_ROOT_DIR>>",
     "runTestsByPath": false,
     "skipFilter": false,
     "testFailureExitCode": 1,
     "testPathPattern": "",
-    "testResultsProcessor": null,
     "testSequencer": "<<REPLACED_JEST_PACKAGES_DIR>>/jest-test-sequencer/build/index.js",
     "updateSnapshot": "all",
     "useStderr": false,
-    "verbose": null,
     "watch": false,
+    "watchAll": false,
     "watchman": true
   },
   "version": "[version]"

packages/jest-cli/src/init/__tests__/__snapshots__/init.test.js.snap

@@ -42,10 +42,10 @@ module.exports = {
   // collectCoverage: false,
 
   // An array of glob patterns indicating a set of files for which coverage information should be collected
-  // collectCoverageFrom: null,
+  // collectCoverageFrom: undefined,
 
   // The directory where Jest should output its coverage files
-  // coverageDirectory: null,
+  // coverageDirectory: undefined,
 
   // An array of regexp pattern strings used to skip coverage collection
   // coveragePathIgnorePatterns: [
@@ -61,10 +61,10 @@ module.exports = {
   // ],
 
   // An object that configures minimum threshold enforcement for coverage results
-  // coverageThreshold: null,
+  // coverageThreshold: undefined,
 
   // A path to a custom dependency extractor
-  // dependencyExtractor: null,
+  // dependencyExtractor: undefined,
 
   // Make calling deprecated APIs throw helpful error messages
   // errorOnDeprecated: false,
@@ -73,10 +73,10 @@ module.exports = {
   // forceCoverageMatch: [],
 
   // A path to a module which exports an async function that is triggered once before all test suites
-  // globalSetup: null,
+  // globalSetup: undefined,
 
   // A path to a module which exports an async function that is triggered once after all test suites
-  // globalTeardown: null,
+  // globalTeardown: undefined,
 
   // A set of global variables that need to be available in all test environments
   // globals: {},
@@ -112,10 +112,10 @@ module.exports = {
   // notifyMode: \\"failure-change\\",
 
   // A preset that is used as a base for Jest's configuration
-  // preset: null,
+  // preset: undefined,
 
   // Run tests from one or more projects
-  // projects: null,
+  // projects: undefined,
 
   // Use this configuration option to add custom reporters to Jest
   // reporters: undefined,
@@ -127,13 +127,13 @@ module.exports = {
   // resetModules: false,
 
   // A path to a custom resolver
-  // resolver: null,
+  // resolver: undefined,
 
   // Automatically restore mock state between every test
   // restoreMocks: false,
 
   // The root directory that Jest should scan for tests and modules within
-  // rootDir: null,
+  // rootDir: undefined,
 
   // A list of paths to directories that Jest should use to search for files in
   // roots: [
@@ -176,7 +176,7 @@ module.exports = {
   // testRegex: [],
 
   // This option allows the use of a custom results processor
-  // testResultsProcessor: null,
+  // testResultsProcessor: undefined,
 
   // This option allows use of a custom test runner
   // testRunner: \\"jasmine2\\",
@@ -188,7 +188,7 @@ module.exports = {
   // timers: \\"real\\",
 
   // A map from regular expressions to paths to transformers
-  // transform: null,
+  // transform: undefined,
 
   // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
   // transformIgnorePatterns: [
@@ -199,7 +199,7 @@ module.exports = {
   // unmockedModulePathPatterns: undefined,
 
   // Indicates whether each individual test should be reported during the run
-  // verbose: null,
+  // verbose: undefined,
 
   // An array of regexp patterns that are matched against all source file paths before re-running tests in watch mode
   // watchPathIgnorePatterns: [],

packages/jest-config/src/Defaults.ts

@@ -21,18 +21,11 @@ const defaultOptions: Config.DefaultOptions = {
   changedFilesWithAncestor: false,
   clearMocks: false,
   collectCoverage: false,
-  collectCoverageFrom: null,
-  coverageDirectory: null,
   coveragePathIgnorePatterns: [NODE_MODULES_REGEXP],
   coverageReporters: ['json', 'text', 'lcov', 'clover'],
-  coverageThreshold: null,
-  dependencyExtractor: null,
   errorOnDeprecated: false,
   expand: false,
-  filter: null,
   forceCoverageMatch: [],
-  globalSetup: null,
-  globalTeardown: null,
   globals: {},
   haste: {
     computeSha1: false,
@@ -48,14 +41,10 @@ const defaultOptions: Config.DefaultOptions = {
   noStackTrace: false,
   notify: false,
   notifyMode: 'failure-change',
-  preset: null,
   prettierPath: 'prettier',
-  projects: null,
   resetMocks: false,
   resetModules: false,
-  resolver: null,
   restoreMocks: false,
-  rootDir: null,
   roots: ['<rootDir>'],
   runTestsByPath: false,
   runner: 'jest-runner',
@@ -70,15 +59,12 @@ const defaultOptions: Config.DefaultOptions = {
   testMatch: ['**/__tests__/**/*.[jt]s?(x)', '**/?(*.)+(spec|test).[tj]s?(x)'],
   testPathIgnorePatterns: [NODE_MODULES_REGEXP],
   testRegex: [],
-  testResultsProcessor: null,
   testRunner: 'jasmine2',
   testSequencer: '@jest/test-sequencer',
   testURL: 'http://localhost',
   timers: 'real',
-  transform: null,
   transformIgnorePatterns: [NODE_MODULES_REGEXP],
   useStderr: false,
-  verbose: null,
   watch: false,
   watchPathIgnorePatterns: [],
   watchman: true,

packages/jest-config/src/__tests__/normalize.test.js

@@ -328,12 +328,12 @@ describe('transform', () => {
     );
 
     expect(options.transform).toEqual([
-      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util'],
-      [DEFAULT_JS_PATTERN, require.resolve('babel-jest')],
-      ['abs-path', '/qux/quux'],
+      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util', {}],
+      [DEFAULT_JS_PATTERN, require.resolve('babel-jest'), {}],
+      ['abs-path', '/qux/quux', {}],
     ]);
   });
-  it("pulls in config if it's passed as an array", () => {
+  it("pulls in config if it's passed as an array, and defaults to empty object", () => {
     const {options} = normalize(
       {
         rootDir: '/root/',
@@ -346,9 +346,9 @@ describe('transform', () => {
       {},
     );
     expect(options.transform).toEqual([
-      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util'],
+      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util', {}],
       [DEFAULT_JS_PATTERN, require.resolve('babel-jest'), {rootMode: 'upward'}],
-      ['abs-path', '/qux/quux'],
+      ['abs-path', '/qux/quux', {}],
     ]);
   });
 });
@@ -822,7 +822,7 @@ describe('Upgrade help', () => {
       {},
     );
 
-    expect(options.transform).toEqual([['.*', '/node_modules/bar/baz']]);
+    expect(options.transform).toEqual([['.*', '/node_modules/bar/baz', {}]]);
     expect(options.transformIgnorePatterns).toEqual([
       joinForPattern('bar', 'baz'),
       joinForPattern('qux', 'quux'),
@@ -1152,8 +1152,8 @@ describe('preset', () => {
       '/node_modules/b',
     ]);
     expect(options.transform).toEqual([
-      ['a', '/node_modules/a'],
-      ['b', '/node_modules/b'],
+      ['a', '/node_modules/a', {}],
+      ['b', '/node_modules/b', {}],
     ]);
   });
 
@@ -1202,10 +1202,10 @@ describe('preset', () => {
     );
 
     expect(options.transform).toEqual([
-      ['e', '/node_modules/ee'],
-      ['b', '/node_modules/bb'],
-      ['c', '/node_modules/cc'],
-      ['a', '/node_modules/aa'],
+      ['e', '/node_modules/ee', {}],
+      ['b', '/node_modules/bb', {}],
+      ['c', '/node_modules/cc', {}],
+      ['a', '/node_modules/aa', {}],
     ]);
   });
 

packages/jest-config/src/normalize.ts

@@ -673,7 +673,7 @@ export default function normalize(
                 key,
                 rootDir: options.rootDir,
               }),
-              ...(Array.isArray(transformElement) ? [transformElement[1]] : []),
+              Array.isArray(transformElement) ? transformElement[1] : {},
             ];
           });
         break;
@@ -947,6 +947,29 @@ export default function normalize(
     newOptions.onlyChanged = newOptions.watch;
   }
 
+  if (!newOptions.onlyChanged) {
+    newOptions.onlyChanged = false;
+  }
+
+  if (!newOptions.lastCommit) {
+    newOptions.lastCommit = false;
+  }
+
+  if (!newOptions.onlyFailures) {
+    newOptions.onlyFailures = false;
+  }
+
+  if (!newOptions.watchAll) {
+    newOptions.watchAll = false;
+  }
+
+  // as any since it can happen. We really need to fix the types here
+  if (
+    newOptions.moduleNameMapper === (DEFAULT_CONFIG.moduleNameMapper as any)
+  ) {
+    newOptions.moduleNameMapper = [];
+  }
+
   newOptions.updateSnapshot =
     argv.ci && !argv.updateSnapshot
       ? 'none'
@@ -1014,6 +1037,26 @@ export default function normalize(
     newOptions.collectCoverageFrom = [];
   }
 
+  if (!newOptions.findRelatedTests) {
+    newOptions.findRelatedTests = false;
+  }
+
+  if (!newOptions.projects) {
+    newOptions.projects = [];
+  }
+
+  if (!newOptions.extraGlobals) {
+    newOptions.extraGlobals = [];
+  }
+
+  if (!newOptions.forceExit) {
+    newOptions.forceExit = false;
+  }
+
+  if (!newOptions.logHeapUsage) {
+    newOptions.logHeapUsage = false;
+  }
+
   return {
     hasDeprecationWarnings,
     options: newOptions,