Class: RuboCop::Cop::Lint::LiteralInInterpolation

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 78

def autocorrected_value(node)
  case node.type
  when :int
    node.children.last.to_i.to_s
  when :float
    node.children.last.to_f.to_s
  when :str
    autocorrected_value_for_string(node)
  when :sym
    autocorrected_value_for_symbol(node)
  when :array
    autocorrected_value_for_array(node)
  when :hash
    autocorrected_value_for_hash(node)
  when :nil
    ''
  else
    node.source.gsub('"', '\"')
  end
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 145

def autocorrected_value_for_array(node)
  return node.source.gsub('"', '\"') unless node.percent_literal?

  contents_range(node).source.split.to_s.gsub('"', '\"')
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 151

def autocorrected_value_for_hash(node)
  hash_string = node.children.map do |child|
    key = autocorrected_value_in_hash(child.key)
    value = autocorrected_value_in_hash(child.value)
    "#{key}=>#{value}"
  end.join(', ')

  "{#{hash_string}}"
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 121

def autocorrected_value_for_string(node)
  if node.source.start_with?("'", '%q')
    node.children.last.inspect[1..-2]
  else
    node.children.last
  end
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 129

def autocorrected_value_for_symbol(node)
  end_pos =
    node.loc.end ? node.loc.end.begin_pos : node.source_range.end_pos

  range_between(node.loc.begin.end_pos, end_pos).source.gsub('"', '\"')
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 162

def autocorrected_value_in_hash(node)
  case node.type
  when :int
    node.children.last.to_i.to_s
  when :float
    node.children.last.to_f.to_s
  when :str
    "\\\"#{node.value.to_s.gsub('"') { '\\\\\"' }}\\\""
  when :sym
    autocorrected_value_in_hash_for_symbol(node)
  when :array
    autocorrected_value_for_array(node)
  when :hash
    autocorrected_value_for_hash(node)
  else
    node.source.gsub('"', '\"')
  end
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 136

def autocorrected_value_in_hash_for_symbol(node)
  # TODO: We need to detect symbol unacceptable names more correctly
  if / |"|'/.match?(node.value.to_s)
    ":\\\"#{node.value.to_s.gsub('"') { '\\\\\"' }}\\\""
  else
    ":#{node.value}"
  end
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 192

def ends_heredoc_line?(node)
  grandparent = node.parent.parent
  return false unless grandparent&.dstr_type? && grandparent.heredoc?

  line = processed_source.lines[node.last_line - 1]
  line.size == node.loc.last_column + 1
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 100

def handle_special_regexp_chars(begin_node, value)
  parent_node = begin_node.parent

  return value unless parent_node.regexp_type? && parent_node.slash_literal? && value['/']

  # When a literal string containing a forward slash preceded by backslashes
  # is interpolated inside a regexp, the number of resultant backslashes in the
  # compiled Regexp is `(2(n+1) / 4)+1`, where `n` is the number of backslashes
  # inside the interpolation.
  # ie. 0-2 backslashes is compiled to 1, 3-6 is compiled to 3, etc.
  # This maintains that same behavior in order to ensure the Regexp behavior
  # does not change upon removing the interpolation.
  value.gsub(%r{(\\*)/}) do
    backslashes = Regexp.last_match[1]
    backslash_count = backslashes.length
    needed_backslashes = (2 * ((backslash_count + 1) / 4)) + 1

    "#{'\\' * needed_backslashes}/"
  end
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 200

def in_array_percent_literal?(node)
  parent = node.parent
  return false unless parent.type?(:dstr, :dsym)

  grandparent = parent.parent
  grandparent&.array_type? && grandparent.percent_literal?
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 57

def offending?(node)
  node &&
    !special_keyword?(node) &&
    prints_as_self?(node) &&
    # Special case for `Layout/TrailingWhitespace`
    !(space_literal?(node) && ends_heredoc_line?(node)) &&
    # Handled by `Lint/ArrayLiteralInRegexp`
    !array_in_regexp?(node)
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 28

def on_interpolation(begin_node)
  final_node = begin_node.children.last
  return unless offending?(final_node)

  # %W and %I split the content into words before expansion
  # treating each interpolation as a word component, so
  # interpolation should not be removed if the expanded value
  # contains a space character.
  expanded_value = autocorrected_value(final_node)
  expanded_value = handle_special_regexp_chars(begin_node, expanded_value)

  return if in_array_percent_literal?(begin_node) && /\s|\A\z/.match?(expanded_value)

  add_offense(final_node) do |corrector|
    next if final_node.dstr_type? # nested, fixed in next iteration

    replacement = if final_node.str_type? && !final_node.value.valid_encoding?
                    final_node.source.delete_prefix('"').delete_suffix('"')
                  else
                    expanded_value
                  end

    corrector.replace(final_node.parent, replacement)
  end
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 183

def prints_as_self?(node)
  node.basic_literal? ||
    (COMPOSITE.include?(node.type) && node.children.all? { |child| prints_as_self?(child) })
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 188

def space_literal?(node)
  node.str_type? && node.value.valid_encoding? && node.value.blank?
end

# File 'lib/rubocop/cop/lint/literal_in_interpolation.rb', line 67

def special_keyword?(node)
  # handle strings like __FILE__
  (node.str_type? && !node.loc.respond_to?(:begin)) || node.source_range.is?('__LINE__')
end