如何在 Rspec-Rails 中引发运行时错误

Question

我必须测试出现一些错误的代码，我尝试了几种技术但都失败了。 class的结构定义如下：

架构控制器：

class SchemasController < ApplicationController
  def index
    @get_schema = Api::AnalyticsQueryBuilderMetadataService::Schema.show
  end
end

Api -> AnalyticsQueryBuilderMetadataService -> Schema.rb文件下的显示方法：

def self.show
        params = { 'limit' => 40 }
        response = Api::Connection.initiate_request('entities', params)
        if response.nil?
           Rails.logger.error 'Data not found for ClientId '
           raise 'Data not found'
        else
           get_schema(response)
        end
end

我为 schema_spec.rb 编写的 Rspec 测试：

require 'rails_helper'
require 'spec_helper'

RSpec.describe Api::AnalyticsQueryBuilderMetadataService::Schema do
  describe 'GET all schema' do
    before do
      # allow_any_instance_of(SchemasController).to receive(:connection).and_return({})
      #binding.pry
      allow(Api::Connection).to receive(:initiate_request).and_return(nil)
    end

    context 'When no json body is passed' do
      it 'Raises NoMethodError' do
        # obj = SchemasController.new
        result = Api::AnalyticsQueryBuilderMetadataService::Schema.show()
        # expect {result}.to raise_error(RuntimeError)
        expect{result}.to raise_error
      end

      
    end
  end
end

但它给出的错误是：

Failures:

  1) Api::AnalyticsQueryBuilderMetadataService::Schema GET all schema When no json body is passed Raises NoMethodError
     Failure/Error: raise 'Data not found'
     
     RuntimeError:
       Data not found
     # ./app/lib/api/analytics_query_builder_metadata_service/schema.rb:22:in `show'
     # ./spec/lib/api/analytics_query_builder_metadata_service/schema_spec.rb:17:in `block (4 levels) in <top (required)>'

Finished in 2.3 seconds (files took 5.63 seconds to load)
44 examples, 1 failure

Failed examples:

rspec ./spec/lib/api/analytics_query_builder_metadata_service/schema_spec.rb:15 # Api::AnalyticsQueryBuilderMetadataService::Schema GET all schema When no json body is passed Raises NoMethodError

帮我解决这个问题。

Answer 1

来自文档；

使用 raise_error 匹配器指定代码块引发错误。

这意味着块中的代码应该是引发错误的代码，但在您的情况下，当您声明result变量时会引发错误。

要使其工作，您可以跳过变量声明并将变量值作为expect块传递；

expect { Api::AnalyticsQueryBuilderMetadataService::Schema.show }
  .to raise_error(StandardError, 'Data not found')