Merge branch 'main' into elenatanasoiu/cop-links

CODEOWNERS

@@ -0,0 +1 @@
+* @github/ruby-architecture-reviewers

CODE_OF_CONDUCT.md

@@ -0,0 +1,73 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to make participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, sex characteristics, gender identity and expression,
+level of experience, education, socio-economic status, nationality, personal
+appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies within all project spaces, and it also applies when
+an individual is representing the project or its community in public spaces.
+Examples of representing a project or community include using an official
+project e-mail address, posting via an official social media account, or acting
+as an appointed representative at an online or offline event. Representation of
+a project may be further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at [email protected]. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org

CONTRIBUTING.md

@@ -0,0 +1,42 @@
+# Contributing
+
+We welcome your contributions to the project. Thank you!
+
+Please note that this project is released with a [Contributor Code of Conduct](CODE_OF_CONDUCT.md). By participating in this project you agree to abide by its terms.
+
+
+## What to contribute
+
+This repository, `rubocop-github`, is part of a broader RuboCop ecosystem.
+
+If the Cop you would like to propose is **generally applicable outside of GitHub**:
+
+1. Propose the change upstream in the core open source project (e.g. [`rubocop`](https://github.com/rubocop/rubocop), or [`rubocop-rails`](https://github.com/rubocop/rubocop-rails)), where it will have maximal visibility and discussion/feedback.
+1. Patch the change provisionally into GitHub's project(s), for immediate benefit; that can include this repository.
+1. ...if the proposal is accepted, remove the patch and pull the updated upstream.
+1. ...if the proposal is not accepted, we usually learn something about our proposal, and we then choose whether to maintain the patch ourselves, discard it, or identify a better open-source home for it.
+
+If the Cop is **only applicable for GitHub**, then this is the right place to propose it.
+
+## How to contribute a Pull Request
+
+1. Fork and clone the repository
+1. [Build it and make sure the tests pass](README.md#Testing) on your machine
+1. Create a new branch: `git checkout -b my-branch-name`
+1. Make your change, add tests, and make sure the tests still pass
+1. Push to your fork and submit a Pull Request
+1. Pat yourself on the back and wait for your pull request to be reviewed and merged.
+
+## For Maintainers
+
+### Releasing a new version
+
+1. Update `rubocop-github.gemspec` with the next version number
+1. Update the `CHANGELOG` with changes and contributor
+1. Run `bundle` to update gem version contained in the lockfile
+1. Make a commit: `Release v{VERSION}`
+1. Tag the commit : `git tag v{VERSION}`
+1. Create the package: `gem build rubocop-github.gemspec`
+1. Push to GitHub: `git push origin && git push origin --tags`
+1. Push to Rubygems: `gem push rubocop-github-{VERSION}.gem`
+1. Publish a new release on GitHub: https://github.com/github/rubocop-github/releases/new

README.md

@@ -1,6 +1,6 @@
 # RuboCop GitHub ![CI](https://github.com/github/rubocop-github/workflows/CI/badge.svg?event=push)
 
-This repository provides recommended RuboCop configuration and additional Cops for use on GitHub open source and internal Ruby projects.
+This repository provides recommended RuboCop configuration and additional Cops for use on GitHub open source and internal Ruby projects, and is the home of [GitHub's Ruby Style Guide](./STYLEGUIDE.md).
 
 ## Usage
 

STYLEGUIDE.md

@@ -27,6 +27,9 @@ This is GitHub's Ruby Style Guide, inspired by [RuboCop's guide][rubocop-guide].
     1. [Conditional keywords](#conditional-keywords)
     2. [Ternary operator](#ternary-operator)
 17. [Syntax](#syntax)
+18. [Rails](#rails)
+    1. [content_for](#content_for)
+    2. [Instance Variables in Views](#instance-variables-in-views)
 
 ## Layout
 
@@ -951,4 +954,129 @@ result = hash.map { |_, v| v + 1 }
 
   Refactoring is even better. It's worth looking hard at any code that explicitly checks types.
 
+## Rails
+
+### content_for
+
+Limit usage of `content_for` helper. The use of `content_for` is the same as setting an instance variable plus `capture`.
+
+``` erb
+<% content_for :foo do %>
+  Hello
+<% end %>
+```
+
+Is effectively the same as
+
+``` erb
+<% @foo_content = capture do %>
+  Hello
+<% end %>
+```
+
+See "Instance Variables in Views" below.
+
+#### Common Anti-patterns
+
+**Using `content_for` within the same template to capture data.**
+
+Instead, just use `capture`.
+
+``` erb
+<!-- bad -->
+<% content_for :page do %>
+  Hello
+<% end %>
+<% if foo? %>
+  <div class="container">
+    <%= yield :page %>
+  </div>
+<% else %>
+  <%= yield :page %>
+<% end %>
+```
+
+Simply capture and use a local variable since the result is only needed in this template.
+
+``` erb
+<!-- good -->
+<% page = capture do %>
+  Hello
+<% end %>
+<% if foo? %>
+  <div class="container">
+    <%= page %>
+  </div>
+<% else %>
+  <%= page %>
+<% end %>
+```
+
+**Using `content_for` to pass content to a subtemplate.**
+
+Instead, `render layout:` with a block.
+
+``` erb
+<!-- bad -->
+<% content_for :page do %>
+  Hello
+<% end %>
+<%= render partial: "page" %>
+<!-- _page.html.erb -->
+<div class="container">
+  <%= yield :page %>
+</div>
+```
+
+Pass the content in a block directly to the `render` function.
+
+``` erb
+<!-- good -->
+<%= render layout: "page" do %>
+  Hello
+<% end %>
+<!-- _page.html.erb -->
+<div class="container">
+  <%= yield %>
+</div>
+```
+
+### Instance Variables in Views
+
+In general, passing data between templates with instance variables is discouraged. This even applies from controllers to templates, not just between partials.
+
+`:locals` can be used to pass data from a controller just like partials.
+
+``` ruby
+def show
+  render "blob/show", locals: {
+    :repository => current_repository,
+    :commit     => current_commit,
+    :blob       => current_blob
+  }
+end
+```
+
+Rails implicit renders are also discouraged.
+
+Always explicitly render templates with a full directory path. This makes template callers easier to trace. You can find all the callers of `"app/view/site/hompage.html.erb"` with a simple project search for `"site/homepage"`.
+
+``` ruby
+def homepage
+  render "site/homepage"
+end
+```
+
+#### Exceptions
+
+There are some known edge cases where you might be forced to use instance variables. In these cases, its okay to do so.
+
+##### Legacy templates
+
+If you need to call a subview that expects an instance variable be set. If possible consider refactoring the subview to accept a local instead.
+
+##### Layouts
+
+Unfortunately the only way to get data into a layout template is with instance variables. You can't explicitly pass locals to them.
+
 [rubocop-guide]: https://github.com/rubocop-hq/ruby-style-guide

config/default.yml

@@ -182,16 +182,14 @@ Layout/HeredocIndentation:
   Enabled: false
 
 Layout/IndentationConsistency:
-  Enabled: false
+  StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#indentation
 
 Layout/IndentationStyle:
-  Enabled: true
   EnforcedStyle: spaces
   IndentationWidth: 2
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#default-indentation
 
 Layout/IndentationWidth:
-  Enabled: true
   Width: 2
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#default-indentation
 
@@ -262,11 +260,9 @@ Layout/SingleLineBlockChain:
   Enabled: false
 
 Layout/SpaceAfterColon:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#spaces-operators
 
 Layout/SpaceAfterComma:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#spaces-operators
 
 Layout/SpaceAfterMethodName:
@@ -276,18 +272,16 @@ Layout/SpaceAfterNot:
   Enabled: true
 
 Layout/SpaceAfterSemicolon:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#spaces-operators
 
 Layout/SpaceAroundBlockParameters:
   Enabled: true
 
 Layout/SpaceAroundEqualsInParameterDefault:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#spaces-around-equals
 
 Layout/SpaceAroundKeyword:
-  Enabled: false
+  StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#spaces-operators
 
 Layout/SpaceAroundMethodCallOperator:
   Enabled: false
@@ -317,7 +311,6 @@ Layout/SpaceInLambdaLiteral:
   Enabled: false
 
 Layout/SpaceInsideArrayLiteralBrackets:
-  Enabled: true
   EnforcedStyle: no_space
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#no-spaces-braces
 
@@ -349,7 +342,6 @@ Layout/TrailingEmptyLines:
   Enabled: true
 
 Layout/TrailingWhitespace:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#trailing-whitespace
 
 Lint/AmbiguousAssignment:
@@ -691,7 +683,7 @@ Lint/UnreachableLoop:
 # TODO: Enable this since it's in the styleguide.
 Lint/UnusedBlockArgument:
   Enabled: false
-  StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#spaces-around-equals
+  StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#underscore-unused-vars
 
 Lint/UnusedMethodArgument:
   Enabled: false
@@ -1090,7 +1082,6 @@ Style/DateTime:
   Enabled: false
 
 Style/DefWithParentheses:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#method-parens-when-arguments
 
 Style/Dir:
@@ -1178,7 +1169,6 @@ Style/FloatDivision:
   Enabled: false
 
 Style/For:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#avoid-for
 
 Style/FormatString:
@@ -1215,7 +1205,6 @@ Style/HashLikeCase:
   Enabled: false
 
 Style/HashSyntax:
-  Enabled: true
   EnforcedStyle: ruby19_no_mixed_keys
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#symbols-as-keys
 
@@ -1316,7 +1305,6 @@ Style/MultilineIfModifier:
   Enabled: false
 
 Style/MultilineIfThen:
-  Enabled: true
   StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#no-then-for-multi-line-if-unless
 
 Style/MultilineInPatternThen:
@@ -1583,8 +1571,8 @@ Style/StringHashKeys:
   Enabled: false
 
 Style/StringLiterals:
-  Enabled: true
   EnforcedStyle: double_quotes
+  StyleGuide: https://github.com/github/rubocop-github/blob/main/STYLEGUIDE.md#double-quotes
 
 Style/StringLiteralsInInterpolation:
   Enabled: false