Ruby Style Guide

Apply these conventions when writing or modifying Ruby code.

Guidelines

• When writing a Ruby script or CLI, always use Thor.
• Prefer double quotes for strings; use single quotes only when the string contains double quotes, in shell commands with interpolation, or when following existing code patterns.
• Use parallel assignment for instance variables when initializing from local variables with matching names; split across two lines when assigning 3 or more.
• Indent private methods by 2 additional spaces after the private keyword.
• Prefer case when over if elsif for multiple conditional branches.
• Put if and unless on a separate line, except when using return or raise without arguments or with one short argument: return if failed?, return false if failed?, raise unless succeeded?, raise error unless succeeded?
• Use guard clauses for early returns.
• Use safe navigation operator (&.) for nil checks.
• Add a blank line after multi-line block headers before the block body.
• Use multi-line, leading-dot chaining when calling more than one method in a row.
• Prefer chaining over temporary variables when it stays readable; then and tap are often helpful.
• Prefer numbered parameters (_1, _2) for small blocks; use it only when numbered params don't work.
• Prefer endless method definitions for simple, single-expression methods that fit within 80 chars.
• Prefer percent notation for arrays of symbols, array of strings, and regexes (%i[foo bar] over [:foo, :bar], %w[foo bar] over ["foo", "bar"] and %r(foo) over /foo/).
• Prefer hash value omission ({ foo:, bar: } over { foo: foo, bar: bar }).
• When a method call with keyword arguments or a hash literal exceeds ~80 chars, break after the first argument using a trailing backslash and align remaining args:

  # bad
  render partial: "webinars/header_image_page", locals: { webinar: requested_resource }, layout: false
  
  # good
  render \
    partial: "webinars/header_image_page",
    locals:  { webinar: requested_resource },
    layout:  false