Gotchas

The purpose of this guide is to document potential "gotchas" that contributors might encounter or should avoid during development of GitLab CE and EE.

Do not assert against the absolute value of a sequence-generated attribute

Consider the following factory:

FactoryBot.definedofactory:labeldosequence(:title){|n|"label#{n}"}endend

Consider the following API spec:

require'rails_helper'describeAPI::Labelsdoit'creates a first label'docreate(:label)getapi("/projects/#{project.id}/labels",user)expect(response).tohave_http_status(200)expect(json_response.first['name']).toeq('label1')endit'creates a second label'docreate(:label)getapi("/projects/#{project.id}/labels",user)expect(response).tohave_http_status(200)expect(json_response.first['name']).toeq('label1')endend

When run, this spec doesn't do what we might expect:

1)API::API reproduce sequence issue creates a second labelFailure/Error: expect(json_response.first['name']).to eq('label1')expected:"label1"got:"label2"(compared using==)

That's because FactoryBot sequences are not reseted for each example.

Please remember that sequence-generated values exist only to avoid having to explicitly set attributes that have a uniqueness constraint when using a factory.

Solution

If you assert against a sequence-generated attribute's value, you should set it explicitly. Also, the value you set shouldn't match the sequence pattern.

For instance, using our:labelfactory, writingcreate(:label, title: 'foo')is ok, butcreate(:label, title: 'label1')is not.

Following is the fixed API spec:

require'rails_helper'describeAPI::Labelsdoit'creates a first label'docreate(:label,标题:'foo')getapi("/projects/#{project.id}/labels",user)expect(response).tohave_http_status(200)expect(json_response.first['name']).toeq('foo')endit'creates a second label'docreate(:label,标题:'bar')getapi("/projects/#{project.id}/labels",user)expect(response).tohave_http_status(200)expect(json_response.first['name']).toeq('bar')endend

Do notrescue Exception

See"Why is it bad style torescue Exception => ein Ruby?".

Note:This rule isenforced automatically by Rubocop.

Do not use inline JavaScript in views

Using the inline:javascriptHaml filters comes with a performance overhead. Using inline JavaScript is not a good way to structure your code and should be avoided.

Note:We've删除这两个过滤器sin an initializer.

Further reading

• Stack Overflow:Why you should not write inline JavaScript