Class: RuboCop::Cop::Style::StringLiterals

# File 'lib/rubocop/cop/style/string_literals.rb', line 71

def all_string_literals?(nodes)
  nodes.all? { |n| n.str_type? || n.dstr_type? }
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 61

def autocorrect(corrector, node)
  StringLiteralCorrector.correct(corrector, node, style)
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 105

def check_multiline_quote_style(node, quote)
  children = node.children
  if unexpected_single_quotes?(quote)
    all_children_with_quotes = children.all? { |c| wrong_quotes?(c) }
    register_offense(node) if all_children_with_quotes
  elsif unexpected_double_quotes?(quote) && !accept_child_double_quotes?(children)
    register_offense(node)
  end
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 75

def detect_quote_styles(node)
  styles = node.children.map { |c| c.loc.begin }

  # For multi-line strings that only have quote marks
  # at the beginning of the first line and the end of
  # the last, the begin and end region of each child
  # is nil. The quote marks are in the parent node.
  return [node.loc.begin.source] if styles.all?(&:nil?)

  styles.map(&:source).uniq
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 87

def message(_node)
  if style == :single_quotes
    "Prefer single-quoted strings when you don't need string " \
      'interpolation or special symbols.'
  else
    'Prefer double-quoted strings unless you need single quotes to ' \
      'avoid extra backslashes for escaping.'
  end
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 97

def offense?(node)
  wrong_quotes?(node) && !inside_interpolation?(node)
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 37

def on_dstr(node)
  # Strings which are continued across multiple lines using \
  # are parsed as a `dstr` node with `str` children
  # If one part of that continued string contains interpolations,
  # then it will be parsed as a nested `dstr` node
  return unless consistent_multiline?
  return if node.heredoc?

  children = node.children
  return unless all_string_literals?(children)

  quote_styles = detect_quote_styles(node)

  if quote_styles.size > 1
    register_offense(node, message: MSG_INCONSISTENT)
  else
    check_multiline_quote_style(node, quote_styles[0])
  end

  ignore_node(node)
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 65

def register_offense(node, message: nil)
  add_offense(node, message: message || message(node)) do |corrector|
    autocorrect(corrector, node)
  end
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 119

def unexpected_double_quotes?(quote)
  quote == '"' && style == :single_quotes
end

# File 'lib/rubocop/cop/style/string_literals.rb', line 115

def unexpected_single_quotes?(quote)
  quote == "'" && style == :double_quotes
end