module Sass::Script::Tree # A SassScript object representing `#{}` interpolation within a string. # # @see Interpolation class StringInterpolation < Node # @return [Literal] The string literal before this interpolation. attr_reader :before # @return [Node] The SassScript within the interpolation attr_reader :mid # @return [StringInterpolation, Literal] # The string literal or string interpolation before this interpolation. attr_reader :after # Whether this is a CSS string or a CSS identifier. The difference is that # strings are written with double-quotes, while identifiers aren't. # # String interpolations are only ever identifiers if they're quote-like # functions such as `url()`. # # @return [Symbol] `:string` or `:identifier` def type @before.value.type end # Returns the quote character that should be used to wrap a Sass # representation of this interpolation. def quote quote_for(self) || '"' end # Interpolation in a string is of the form `"before #{mid} after"`, # where `before` and `after` may include more interpolation. # # @param before [StringInterpolation, Literal] See {StringInterpolation#before} # @param mid [Node] See {StringInterpolation#mid} # @param after [Literal] See {StringInterpolation#after} def initialize(before, mid, after) @before = before @mid = mid @after = after end # @return [String] A human-readable s-expression representation of the interpolation def inspect "(string_interpolation #{@before.inspect} #{@mid.inspect} #{@after.inspect})" end # @see Node#to_sass def to_sass(opts = {}) quote = type == :string ? opts[:quote] || quote_for(self) || '"' : :none opts = opts.merge(:quote => quote) res = "" res << quote if quote != :none res << _to_sass(before, opts) res << '#{' << @mid.to_sass(opts.merge(:quote => nil)) << '}' res << _to_sass(after, opts) res << quote if quote != :none res end # Returns the three components of the interpolation, `before`, `mid`, and `after`. # # @return [Array] # @see #initialize # @see Node#children def children [@before, @mid, @after].compact end # @see Node#deep_copy def deep_copy node = dup node.instance_variable_set('@before', @before.deep_copy) if @before node.instance_variable_set('@mid', @mid.deep_copy) node.instance_variable_set('@after', @after.deep_copy) if @after node end protected # Evaluates the interpolation. # # @param environment [Sass::Environment] The environment in which to evaluate the SassScript # @return [Sass::Script::Value::String] # The SassScript string that is the value of the interpolation def _perform(environment) res = "" before = @before.perform(environment) res << before.value mid = @mid.perform(environment) res << (mid.is_a?(Sass::Script::Value::String) ? mid.value : mid.to_s(:quote => :none)) res << @after.perform(environment).value opts(Sass::Script::Value::String.new(res, before.type)) end private def _to_sass(string_or_interp, opts) result = string_or_interp.to_sass(opts) opts[:quote] == :none ? result : result.slice(1...-1) end def quote_for(string_or_interp) if string_or_interp.is_a?(Sass::Script::Tree::Literal) return nil if string_or_interp.value.value.empty? return '"' if string_or_interp.value.value.include?("'") return "'" if string_or_interp.value.value.include?('"') return nil end # Double-quotes take precedence over single quotes. before_quote = quote_for(string_or_interp.before) return '"' if before_quote == '"' after_quote = quote_for(string_or_interp.after) return '"' if after_quote == '"' # Returns "'" if either or both insist on single quotes, and nil # otherwise. before_quote || after_quote end end end