@stryker-mutator/core/src/process/2-mutant-instrumenter-executor.ts

The extendable JavaScript mutation testing framework

import { execaCommand } from 'execa';
import { Injector, tokens, commonTokens, PluginContext } from '@stryker-mutator/api/plugin';
import { createInstrumenter, InstrumentResult } from '@stryker-mutator/instrumenter';
import { StrykerOptions } from '@stryker-mutator/api/core';
import { Reporter } from '@stryker-mutator/api/report';
import { I } from '@stryker-mutator/util';

import { coreTokens } from '../di/index.js';
import { Sandbox } from '../sandbox/sandbox.js';
import { LoggingClientContext } from '../logging/index.js';
import { ConcurrencyTokenProvider, createCheckerPool } from '../concurrent/index.js';
import { createCheckerFactory } from '../checker/index.js';
import { createPreprocessor } from '../sandbox/index.js';
import { Timer } from '../utils/timer.js';
import { TemporaryDirectory } from '../utils/temporary-directory.js';
import { UnexpectedExitHandler } from '../unexpected-exit-handler.js';
import { FileSystem, Project } from '../fs/index.js';

import { IdGenerator } from '../child-proxy/id-generator.js';

import { DryRunContext } from './3-dry-run-executor.js';

export interface MutantInstrumenterContext extends PluginContext {
  [commonTokens.options]: StrykerOptions;
  [coreTokens.project]: Project;
  [coreTokens.loggingContext]: LoggingClientContext;
  [coreTokens.reporter]: Required<Reporter>;
  [coreTokens.timer]: I<Timer>;
  [coreTokens.temporaryDirectory]: I<TemporaryDirectory>;
  [coreTokens.execa]: typeof execaCommand;
  [coreTokens.process]: NodeJS.Process;
  [coreTokens.unexpectedExitRegistry]: I<UnexpectedExitHandler>;
  [coreTokens.pluginModulePaths]: readonly string[];
  [coreTokens.fs]: I<FileSystem>;
}

export class MutantInstrumenterExecutor {
  public static readonly inject = tokens(commonTokens.injector, coreTokens.project, commonTokens.options);
  constructor(
    private readonly injector: Injector<MutantInstrumenterContext>,
    private readonly project: Project,
    private readonly options: StrykerOptions,
  ) {}

  public async execute(): Promise<Injector<DryRunContext>> {
    // Create the checker and instrumenter
    const instrumenter = this.injector.injectFunction(createInstrumenter);

    // Instrument files in-memory
    const instrumentResult = await instrumenter.instrument(await this.readFilesToMutate(), this.options.mutator);

    // Preprocess the project
    const preprocess = this.injector.injectFunction(createPreprocessor);
    this.writeInstrumentedFiles(instrumentResult);
    await preprocess.preprocess(this.project);

    // Initialize the checker pool
    const concurrencyTokenProviderProvider = this.injector.provideClass(coreTokens.concurrencyTokenProvider, ConcurrencyTokenProvider);
    const concurrencyTokenProvider = concurrencyTokenProviderProvider.resolve(coreTokens.concurrencyTokenProvider);

    const checkerPoolProvider = concurrencyTokenProviderProvider
      .provideValue(coreTokens.checkerConcurrencyTokens, concurrencyTokenProvider.checkerToken$)
      .provideClass(coreTokens.workerIdGenerator, IdGenerator)
      .provideFactory(coreTokens.checkerFactory, createCheckerFactory)
      .provideFactory(coreTokens.checkerPool, createCheckerPool);
    const checkerPool = checkerPoolProvider.resolve(coreTokens.checkerPool);
    await checkerPool.init();

    // Feed the sandbox
    const dryRunProvider = checkerPoolProvider.provideClass(coreTokens.sandbox, Sandbox).provideValue(coreTokens.mutants, instrumentResult.mutants);
    const sandbox = dryRunProvider.resolve(coreTokens.sandbox);
    await sandbox.init();
    return dryRunProvider;
  }

  private readFilesToMutate() {
    return Promise.all([...this.project.filesToMutate.values()].map((file) => file.toInstrumenterFile()));
  }

  private writeInstrumentedFiles(instrumentResult: InstrumentResult): void {
    for (const { name, content } of Object.values(instrumentResult.files)) {
      this.project.files.get(name)!.setContent(content);
    }
  }
}