docs: function reportReducer (linter, summary, filePath) {
    const fileContents = fs.readFileSync(filePath, {encoding: 'utf8'})
    const file = linter.process(fileContents)
  
    if (file.messages.length !== 0) {
      this.printFilePath(filePath)
  
      file.messages.forEach((message) => {
        const severity = message.fatal ? 'error' : 'warning'
        this.printLintItem(message.line, message.column, severity, message.message, message.ruleId)
  
        if (message.fatal) {
          summary.errors += 1
        } else {
          summary.warnings += 1
        }
      })
  
      console.log('') // logging empty line
    }
  
    return summary
  }