jest.conf.js

const tsconfig = require('../../../tsconfig.json');

module.exports = {
    preset: 'jest-preset-angular',
    setupFiles: ['jest-date-mock'],
    setupFilesAfterEnv: ['<rootDir>/src/test/javascript/jest.ts'],
    cacheDirectory: '<rootDir>/target/jest-cache',
    coverageDirectory: '<rootDir>/target/test-results/',
    globals: {
        'ts-jest': {
            stringifyContentPathRegex: '\\.html$',
            tsConfig: '<rootDir>/tsconfig.json',
            astTransformers: ['jest-preset-angular/build/InlineFilesTransformer', 'jest-preset-angular/build/StripStylesTransformer']
        }
    },
    coveragePathIgnorePatterns: [
        '<rootDir>/src/test/javascript'
    ],
    moduleNameMapper: mapTypescriptAliasToJestAlias(),
    reporters: [
        'default',
        [ 'jest-junit', { outputDirectory: './target/test-results/', outputName: 'TESTS-results-jest.xml' } ]
    ],
    testResultsProcessor: 'jest-sonar-reporter',
    transformIgnorePatterns: ['node_modules/'],
    testMatch: ['<rootDir>/src/test/javascript/spec/**/@(*.)@(spec.ts)'],
    rootDir: '../../../',
    testURL: 'http://localhost/'
};

function mapTypescriptAliasToJestAlias(alias = {}) {
    const jestAliases = { ...alias };
    if (!tsconfig.compilerOptions.paths) {
        return jestAliases;
    }
    Object.entries(tsconfig.compilerOptions.paths)
        .filter(([key, value]) => {
            // use Typescript alias in Jest only if this has value
            if (value.length) {
                return true;
            }
            return false;
        })
        .map(([key, value]) => {
            // if Typescript alias ends with /* then in Jest:
            // - alias key must end with /(.*)
            // - alias value must end with /$1
            const regexToReplace = /(.*)\/\*$/;
            const aliasKey = key.replace(regexToReplace, '$1/(.*)');
            const aliasValue = value[0].replace(regexToReplace, '$1/$$1');
            return [aliasKey, `<rootDir>/${aliasValue}`];
        })
        .reduce((aliases, [key, value]) => {
            aliases[key] = value;
            return aliases;
        }, jestAliases);
    return jestAliases;
}