NoMethodError：[]：Array的未定义方法`errors'

Question

当我为下面的代码运行test时，我得到NoM​​ethodError

csv_importer.rb

require 'csv_importer/engine'

class WebImport
  def initialize(url)
    @url = url
  end

  def call
    url = 'http://example.com/people.csv'
    csv_string = open(url).read.force_encoding('UTF-8')

    string_to_users(csv_string)
  end

  def string_to_users(csv_string)
    counter = 0
    duplicate_counter = 0

    user = []
    CSV.parse(csv_string, headers: true, header_converters: :symbol) do |row|
      next unless row[:name].present? && row[:email_address].present?
      user = CsvImporter::User.create row.to_h
      if user.persisted?
        counter += 1
      else
        duplicate_counter += 1
      end
    end
    p "Email duplicate record: #{user.email_address} - #{user.errors.full_messages.join(',')}" if user.errors.any?

    p "Imported #{counter} users, #{duplicate_counter} duplicate rows ain't added in total"
  end
end

csv_importer_test.rb

require 'csv_importer/engine'
require 'test_helper'
require 'rake'

class CsvImporterTest < ActiveSupport::TestCase

  test 'truth' do
    assert_kind_of Module, CsvImporter
  end

  test 'should override_application and import data' do
    a = WebImport.new(url: 'http://example.com/people.csv')
    a.string_to_users('Olaoluwa Afolabi')# <-- I still get error even I put a comma separated list of attributes that is imported into the db here.
    assert_equal User.count, 7
  end
end

代码中网址的csv格式： 一旦我运行Rake任务

，这将保存到DB中

Name,Email Address,Telephone Number,Website
Coy Kunde,stone@stone.com,0800 382630,mills.net

我做了多少调试：

我使用byebug并且我在csv_importer_test.rb中找到了a.string_to_users('Olaoluwa Afolabi')所在的行rails test正在抛出错误。请参阅下面的byebug错误：

所以，当我运行web3.eth.getBalance(address)时，我收到以下错误：

那么，我如何解决这个错误，我不知道到底做错了什么？

Answer 1

如果您的csv_string中没有任何行，则此行：

user = CsvImporter::User.create row.to_h

未执行，因此user变量包含以前的值，即[]：

user = []

我们知道，errors没有定义Array方法，但您尝试在此行中调用它：

p "Email duplicate record: #{user.email_address} - #{user.errors.full_messages.join(',')}" if user.errors.any?

这就是你收到错误的原因。