code: function fillFileTree (fileTree, fileList) {
    let extname
  
    fileList.forEach(filePath => {
      extname = path.extname(filePath)
      const linters = Object.keys(linterSuffix)
  
      const match = linters.some(linterName => {
        if (linterSuffix[linterName].includes(extname)) {
          fileTree[linterName].push(filePath)
          return true
        }
  
        return false
      })
  
      // 没有匹配到特定的 linter，则分配给所有 linter
      if (!match) {
        linters.forEach(linterName => {
          fileTree[linterName].push(filePath)
        })
      }
    })
  
    return fileTree
  }
docs: 填充 fileTree
  
  @param {object} fileTree file tree
  @param {Array<string>} fileList file list
  @returns {object} filled file tree