check sourcesRelatedToTestsInChangedFiles in shouldInstrument

e2e/__tests__/onlyChanged.test.ts

@@ -137,6 +137,39 @@ test('report test coverage for only changed files', () => {
   expect(stdout).not.toMatch('b.js');
 });
 
+test('report test coverage of source on test file change under only changed files', () => {
+  writeFiles(DIR, {
+    '__tests__/a.test.js': `
+    require('../a');
+    test('a1', () => expect(1).toBe(1));
+  `,
+    'a.js': 'module.exports = {}',
+    'package.json': JSON.stringify({
+      jest: {
+        collectCoverage: true,
+        coverageReporters: ['text'],
+        testEnvironment: 'node',
+      },
+    }),
+  });
+
+  run(`${GIT} init`, DIR);
+  run(`${GIT} add .`, DIR);
+  run(`${GIT} commit --no-gpg-sign -m "first"`, DIR);
+
+  writeFiles(DIR, {
+    '__tests__/a.test.js': `
+    require('../a');
+    test('a1', () => expect(1).toBe(1));
+    test('a2', () => expect(2).toBe(2));
+  `,
+  });
+
+  const {stdout} = runJest(DIR, ['-o']);
+
+  expect(stdout).toMatch('a.js');
+});
+
 test('do not pickup non-tested files when reporting coverage on only changed files', () => {
   writeFiles(DIR, {
     'a.js': 'module.exports = {}',

packages/jest-core/src/TestScheduler.ts

@@ -44,6 +44,7 @@ export type TestSchedulerContext = {
   firstRun: boolean;
   previousSuccess: boolean;
   changedFiles?: Set<Config.Path>;
+  sourcesRelatedToTestsInChangedFiles?: Set<Config.Path>;
 };
 export default class TestScheduler {
   private _dispatcher: ReporterDispatcher;
@@ -181,6 +182,8 @@ export default class TestScheduler {
         const Runner: typeof TestRunner = require(config.runner);
         testRunners[config.runner] = new Runner(this._globalConfig, {
           changedFiles: this._context && this._context.changedFiles,
+          sourcesRelatedToTestsInChangedFiles:
+            this._context && this._context.sourcesRelatedToTestsInChangedFiles,
         });
       }
     });
@@ -273,6 +276,8 @@ export default class TestScheduler {
       this.addReporter(
         new CoverageReporter(this._globalConfig, {
           changedFiles: this._context && this._context.changedFiles,
+          sourcesRelatedToTestsInChangedFiles:
+            this._context && this._context.sourcesRelatedToTestsInChangedFiles,
         }),
       );
     }
@@ -303,6 +308,8 @@ export default class TestScheduler {
       this.addReporter(
         new CoverageReporter(this._globalConfig, {
           changedFiles: this._context && this._context.changedFiles,
+          sourcesRelatedToTestsInChangedFiles:
+            this._context && this._context.sourcesRelatedToTestsInChangedFiles,
         }),
       );
     }

packages/jest-core/src/runJest.ts

@@ -242,9 +242,22 @@ export default async function runJest({
   }
 
   if (changedFilesPromise) {
-    testSchedulerContext.changedFiles = (
-      await changedFilesPromise
-    ).changedFiles;
+    const changedFilesInfo = await changedFilesPromise;
+    testSchedulerContext.changedFiles = changedFilesInfo.changedFiles;
+    if (testSchedulerContext.changedFiles) {
+      const sourcesRelatedToTestsInChangedFilesArray = contexts
+        .map(context => {
+          const searchSource = new SearchSource(context);
+          const relatedSourceFromTestsInChangedFiles = searchSource.findRelatedSourcesFromTestsInChangedFiles(
+            changedFilesInfo,
+          );
+          return relatedSourceFromTestsInChangedFiles;
+        })
+        .reduce((total, paths) => [...total, ...paths], []);
+      testSchedulerContext.sourcesRelatedToTestsInChangedFiles = new Set(
+        sourcesRelatedToTestsInChangedFilesArray,
+      );
+    }
   }
 
   const results = await new TestScheduler(

packages/jest-reporters/src/__tests__/coverage_worker.test.js

@@ -41,6 +41,7 @@ test('resolves to the result of generateEmptyCoverage upon success', async () =>
     globalConfig,
     config,
     undefined,
+    undefined,
   );
 
   expect(result).toEqual(42);

packages/jest-reporters/src/coverage_reporter.ts

@@ -204,6 +204,9 @@ export default class CoverageReporter extends BaseReporter {
               changedFiles:
                 this._options.changedFiles &&
                 Array.from(this._options.changedFiles),
+              sourcesRelatedToTestsInChangedFiles:
+                this._options.sourcesRelatedToTestsInChangedFiles &&
+                Array.from(this._options.sourcesRelatedToTestsInChangedFiles),
             },
             path: filename,
           });

packages/jest-reporters/src/coverage_worker.ts

@@ -41,5 +41,8 @@ export function worker({
     globalConfig,
     config,
     options && options.changedFiles && new Set(options.changedFiles),
+    options &&
+      options.sourcesRelatedToTestsInChangedFiles &&
+      new Set(options.sourcesRelatedToTestsInChangedFiles),
   );
 }

packages/jest-reporters/src/generateEmptyCoverage.ts

@@ -31,13 +31,15 @@ export default function (
   globalConfig: Config.GlobalConfig,
   config: Config.ProjectConfig,
   changedFiles?: Set<Config.Path>,
+  sourcesRelatedToTestsInChangedFiles?: Set<Config.Path>,
 ): CoverageWorkerResult | null {
   const coverageOptions = {
     changedFiles,
     collectCoverage: globalConfig.collectCoverage,
     collectCoverageFrom: globalConfig.collectCoverageFrom,
     collectCoverageOnlyFrom: globalConfig.collectCoverageOnlyFrom,
     coverageProvider: globalConfig.coverageProvider,
+    sourcesRelatedToTestsInChangedFiles,
   };
   let coverageWorkerResult: CoverageWorkerResult | null = null;
   if (shouldInstrument(filename, coverageOptions, config)) {

packages/jest-reporters/src/types.ts

@@ -37,10 +37,12 @@ export type CoverageWorker = {worker: typeof worker};
 
 export type CoverageReporterOptions = {
   changedFiles?: Set<Config.Path>;
+  sourcesRelatedToTestsInChangedFiles?: Set<Config.Path>;
 };
 
 export type CoverageReporterSerializedOptions = {
   changedFiles?: Array<Config.Path>;
+  sourcesRelatedToTestsInChangedFiles?: Array<Config.Path>;
 };
 
 export type OnTestStart = (test: Test) => Promise<void>;

packages/jest-runner/src/runTest.ts

@@ -159,6 +159,8 @@ async function runTestInternal(
     collectCoverageFrom: globalConfig.collectCoverageFrom,
     collectCoverageOnlyFrom: globalConfig.collectCoverageOnlyFrom,
     coverageProvider: globalConfig.coverageProvider,
+    sourcesRelatedToTestsInChangedFiles:
+      context && context.sourcesRelatedToTestsInChangedFiles,
   });
 
   const start = Date.now();

packages/jest-runner/src/types.ts

@@ -51,6 +51,7 @@ export type TestRunnerOptions = {
 
 export type TestRunnerContext = {
   changedFiles?: Set<Config.Path>;
+  sourcesRelatedToTestsInChangedFiles?: Set<Config.Path>;
 };
 
 export type TestRunnerSerializedContext = {

packages/jest-runtime/src/index.ts

@@ -141,6 +141,7 @@ class Runtime {
       collectCoverageFrom: [],
       collectCoverageOnlyFrom: undefined,
       coverageProvider: 'babel',
+      sourcesRelatedToTestsInChangedFiles: undefined,
     };
     this._currentlyExecutingModulePath = '';
     this._environment = environment;

packages/jest-transform/src/shouldInstrument.ts

@@ -93,8 +93,15 @@ export default function shouldInstrument(
     return false;
   }
 
-  if (options.changedFiles && !options.changedFiles.has(filename)) {
-    return false;
+  if (options.changedFiles) {
+    if (!options.changedFiles.has(filename)) {
+      if (!options.sourcesRelatedToTestsInChangedFiles) {
+        return false;
+      }
+      if (!options.sourcesRelatedToTestsInChangedFiles.has(filename)) {
+        return false;
+      }
+    }
   }
 
   return true;

packages/jest-transform/src/types.ts

@@ -16,6 +16,7 @@ export type ShouldInstrumentOptions = Pick<
   | 'coverageProvider'
 > & {
   changedFiles?: Set<Config.Path>;
+  sourcesRelatedToTestsInChangedFiles?: Set<Config.Path>;
 };
 
 export type Options = ShouldInstrumentOptions &