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

Author: SimenB

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))
 

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/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,

packages/jest-haste-map/src/index.ts

@@ -54,7 +54,7 @@ type Options = {
   computeDependencies?: boolean;
   computeSha1?: boolean;
   console?: Console;
-  dependencyExtractor?: string;
+  dependencyExtractor?: string | null;
   extensions: Array<string>;
   forceNodeFilesystemAPI?: boolean;
   hasteImplModulePath?: string;
@@ -79,7 +79,7 @@ type InternalOptions = {
   cacheDirectory: string;
   computeDependencies: boolean;
   computeSha1: boolean;
-  dependencyExtractor?: string;
+  dependencyExtractor: string | null;
   extensions: Array<string>;
   forceNodeFilesystemAPI: boolean;
   hasteImplModulePath?: string;
@@ -251,7 +251,7 @@ class HasteMap extends EventEmitter {
           ? true
           : options.computeDependencies,
       computeSha1: options.computeSha1 || false,
-      dependencyExtractor: options.dependencyExtractor,
+      dependencyExtractor: options.dependencyExtractor || null,
       extensions: options.extensions,
       forceNodeFilesystemAPI: !!options.forceNodeFilesystemAPI,
       hasteImplModulePath: options.hasteImplModulePath,

packages/jest-haste-map/src/types.ts

@@ -16,7 +16,7 @@ export type Mapper = (item: string) => Array<string> | null;
 export type WorkerMessage = {
   computeDependencies: boolean;
   computeSha1: boolean;
-  dependencyExtractor?: string;
+  dependencyExtractor?: string | null;
   rootDir: string;
   filePath: string;
   hasteImplModulePath?: string;

packages/jest-reporters/src/coverage_reporter.ts

@@ -107,7 +107,7 @@ export default class CoverageReporter extends BaseReporter {
       );
     }
 
-    this._checkThreshold(this._globalConfig, map);
+    this._checkThreshold(map);
   }
 
   private async _addUntestedFiles(
@@ -209,11 +209,10 @@ export default class CoverageReporter extends BaseReporter {
     }
   }
 
-  private _checkThreshold(
-    globalConfig: Config.GlobalConfig,
-    map: istanbulCoverage.CoverageMap,
-  ) {
-    if (globalConfig.coverageThreshold) {
+  private _checkThreshold(map: istanbulCoverage.CoverageMap) {
+    const {coverageThreshold} = this._globalConfig;
+
+    if (coverageThreshold) {
       function check(
         name: string,
         thresholds: Config.CoverageThresholdValue,
@@ -250,7 +249,7 @@ export default class CoverageReporter extends BaseReporter {
         PATH: 'path',
       };
       const coveredFiles = map.files();
-      const thresholdGroups = Object.keys(globalConfig.coverageThreshold);
+      const thresholdGroups = Object.keys(coverageThreshold);
       const groupTypeByThresholdGroup: {[index: string]: string} = {};
       const filesByGlob: {[index: string]: Array<string>} = {};
 
@@ -342,7 +341,7 @@ export default class CoverageReporter extends BaseReporter {
               errors = errors.concat(
                 check(
                   thresholdGroup,
-                  globalConfig.coverageThreshold[thresholdGroup],
+                  coverageThreshold[thresholdGroup],
                   coverage,
                 ),
               );
@@ -357,7 +356,7 @@ export default class CoverageReporter extends BaseReporter {
               errors = errors.concat(
                 check(
                   thresholdGroup,
-                  globalConfig.coverageThreshold[thresholdGroup],
+                  coverageThreshold[thresholdGroup],
                   coverage,
                 ),
               );
@@ -370,7 +369,7 @@ export default class CoverageReporter extends BaseReporter {
                 errors = errors.concat(
                   check(
                     fileMatchingGlob,
-                    globalConfig.coverageThreshold[thresholdGroup],
+                    coverageThreshold[thresholdGroup],
                     map.fileCoverageFor(fileMatchingGlob).toSummary(),
                   ),
                 );

packages/jest-resolve/src/types.ts

@@ -14,7 +14,7 @@ export type ResolverConfig = {
   hasCoreModules: boolean;
   moduleDirectories: Array<string>;
   moduleNameMapper?: Array<ModuleNameMapperConfig> | null;
-  modulePaths: Array<Config.Path>;
+  modulePaths?: Array<Config.Path>;
   platforms?: Array<string>;
   resolver?: Config.Path | null;
   rootDir: Config.Path;

packages/jest-runtime/src/cli/index.ts

@@ -68,10 +68,9 @@ export function run(cliArgv?: Config.Argv, cliInfo?: Array<string>) {
   const options = readConfig(argv, root);
   const globalConfig = options.globalConfig;
   // Always disable automocking in scripts.
-  const config = {
+  const config: Config.ProjectConfig = {
     ...options.projectConfig,
     automock: false,
-    unmockedModulePathPatterns: null,
   };
 
   // Break circular dependency

packages/jest-runtime/src/index.ts

@@ -123,7 +123,7 @@ class Runtime {
       changedFiles: undefined,
       collectCoverage: false,
       collectCoverageFrom: [],
-      collectCoverageOnlyFrom: null,
+      collectCoverageOnlyFrom: undefined,
     };
     this._currentlyExecutingModulePath = '';
     this._environment = environment;
@@ -489,7 +489,7 @@ class Runtime {
       collectCoverage: this._coverageOptions.collectCoverage,
       collectCoverageFrom: this._coverageOptions.collectCoverageFrom,
       collectCoverageOnlyFrom: this._coverageOptions.collectCoverageOnlyFrom,
-      extraGlobals: this._config.extraGlobals || [],
+      extraGlobals: this._config.extraGlobals,
     };
   }
 
@@ -713,7 +713,6 @@ class Runtime {
     Object.defineProperty(localModule, 'require', {
       value: this._createRequireImplementation(localModule, options),
     });
-    const extraGlobals = this._config.extraGlobals || [];
     const transformedFile = this._scriptTransformer.transform(
       filename,
       this._getFullTransformationOptions(options),
@@ -750,7 +749,7 @@ class Runtime {
         filename,
         localModule.require as LocalModuleRequire,
       ), // jest object
-      ...extraGlobals.map(globalVariable => {
+      ...this._config.extraGlobals.map(globalVariable => {
         if (this._environment.global[globalVariable]) {
           return this._environment.global[globalVariable];
         }

packages/jest-transform/src/ScriptTransformer.ts

@@ -361,7 +361,7 @@ export default class ScriptTransformer {
       (this.shouldTransform(filename) || instrument);
 
     try {
-      const extraGlobals = (options && options.extraGlobals) || [];
+      const extraGlobals = options ? options.extraGlobals : [];
 
       if (willTransform) {
         const transformedSource = this.transformSource(