message: refactor: use assign from utils to more easily replace it in the future
diff: @@ -11,6 +11,7 @@ import {
  validatePatterns
  } from "./lexer"
  import {
  + assign,
  cloneArr,
  cloneObj,
  forEach,
  @@ -124,7 +125,7 @@ export class Lexer {
  }
  // todo: defaults func?
  - this.config = Object.assign({}, DEFAULT_LEXER_CONFIG, config)
  + this.config = assign({}, DEFAULT_LEXER_CONFIG, config) as any
  const traceInitVal = this.config.traceInitPerf
  if (traceInitVal === true) {
  @@ -260,11 +261,11 @@ export class Lexer {
  this.charCodeToPatternIdxToConfig[currModName] =
  currAnalyzeResult.charCodeToPatternIdxToConfig
  - this.emptyGroups = Object.assign(
  + this.emptyGroups = assign(
  {},
  this.emptyGroups,
  currAnalyzeResult.emptyGroups
  - )
  + ) as any
  this.hasCustom = currAnalyzeResult.hasCustom || this.hasCustom
  