Remove instance variables in generated specs

[nekketsuuu]

Problem

I noticed some generated scaffold specs contain explicit instance variable gets and sets. But rubocop-rspec gem, at least v2.10.0, prefers no instance variable usages in specs by default (RSpec/InstanceVariable cop, introduced in 2014 rubocop/rubocop-rspec#3).

In fact, I confirmed that some specs such as spec/views/posts/edit.html.erb_spec.rb generated by bin/rails g scaffold post are offended by rubocop.

What I Changed

Therefore, I removed usage of instance variables from generated specs.

For historians, commits in 2010 (f06aa50 and 0d244a1) introduce the use of instance variables, maybe without strong reasons.

Changes to Specs

The following table is a summary of changes to generated edit_spec.rb. I generated these results on my local environment with Rails 7.0.2.4 and rspec-{core,expectations,mocks,support} 3.12.0.pre. Specs in "After" column do not contain @post.

Context	Before	After
Without attributes	require 'rails_helper' RSpec.describe "posts/edit", type: :view do before(:each) do @post = assign(:post, Post.create!()) end it "renders the edit post form" do render assert_select "form[action=?][method=?]", post_path(@post), "post" do end end end	require 'rails_helper' RSpec.describe "posts/edit", type: :view do let(:post) { Post.create!() } before(:each) do assign(:post, post) end it "renders the edit post form" do render assert_select "form[action=?][method=?]", post_path(post), "post" do end end end
With an attribute	require 'rails_helper' RSpec.describe "posts/edit", type: :view do before(:each) do @post = assign(:post, Post.create!( content: "MyText" )) end it "renders the edit post form" do render assert_select "form[action=?][method=?]", post_path(@post), "post" do assert_select "textarea[name=?]", "post[content]" end end end	require 'rails_helper' RSpec.describe "posts/edit", type: :view do let(:post) { Post.create!( content: "MyText" ) } before(:each) do assign(:post, post) end it "renders the edit post form" do render assert_select "form[action=?][method=?]", post_path(post), "post" do assert_select "textarea[name=?]", "post[content]" end end end
With two attributes	require 'rails_helper' RSpec.describe "posts/edit", type: :view do before(:each) do @post = assign(:post, Post.create!( content: "MyText", priority: 1 )) end it "renders the edit post form" do render assert_select "form[action=?][method=?]", post_path(@post), "post" do assert_select "textarea[name=?]", "post[content]" assert_select "input[name=?]", "post[priority]" end end end	require 'rails_helper' RSpec.describe "posts/edit", type: :view do let(:post) { Post.create!( content: "MyText", priority: 1 ) } before(:each) do assign(:post, post) end it "renders the edit post form" do render assert_select "form[action=?][method=?]", post_path(post), "post" do assert_select "textarea[name=?]", "post[content]" assert_select "input[name=?]", "post[priority]" end end end

[pirj]

Is it the only change needed for generated specs to pass the RuboCop check?
I can think of e.g. RSpec/HookArgument cop that might be triggered by before(:each), as its default enforced style is "implicit", and it is enabled by default.

[nekketsuuu]

Is it the only change needed for generated specs to pass the RuboCop check?

Nice point. No, other cops such as Style/StringLiterals by rubocop gem are triggered. Almost all triggered cops are, however, able to auto-corrected by rubocop. The only exceptions I found are RSpec/InstanceVariable cop and Metrics/BlockLength cop.

So I want to change generated codes beforehand for RSpec/InstanceVariable. Also I don't touch for Metrics/BlockLength because many generated specs can be offended by that cop when attributes are too many (and I personally prefer to ignore Metrics/BlockLength for specs).

This is why I only changed usage of instance variables in this pull request. Thank you for pointing it out.

[pirj]

Thank you!