\node_modules\fork-ts-checker-webpack-plugin\lib\service.js:49
    : new IncrementalChecker_1.IncrementalChecker(typescript, exports.createNormalizedMessageFromDiagnostic, exports.createNormalizedMessageFromRuleFailure, process.env.TSCONFIG, JSON.parse(process.env.COMPILER_OPTIONS), process.env.CONTEXT, process.env.TSLINT === 'true' ? true : process.env.TSLINT || false, process.env.TSLINTAUTOFIX === 'true', process.env.WATCH === '' ? [] : process.env.WATCH.split('|'), parseInt(process.env.WORK_NUMBER, 10) || 0, parseInt(process.env.WORK_DIVISION, 10) || 1, process.env.CHECK_SYNTACTIC_ERRORS === 'true', process.env.VUE === 'true', resolveModuleName, resolveTypeReferenceDirective);

TypeError: Cannot read property 'split' of undefined
    at Object.<anonymous> (\node_modules\fork-ts-checker-webpack-plugin\lib\service.js:49:399)
    at Module._compile (module.js:635:30)