Refactor PredicateBuilder

lib/mobility/plugins/query.rb

@@ -75,34 +75,41 @@ def map(opts, locale, invert: false)
 
  attrs_opts = opts.slice(*i18n_keys)
 
- predicate_builder = PredicateBuilder.new(attrs.backend_class)
+ predicate_builder = PredicateBuilder.new(attrs)
  predicates += i18n_keys.map do |key|
- predicate_builder.build(key, locale, opts.delete(key), attrs.options)
+ predicate_builder.build(key, locale, opts.delete(key), invert)
  end
 
  [attrs, attrs_opts]
  }.compact
 
- # TODO: inline this
- inverter = ::ActiveRecord::Relation::WhereClause.new([]).method(:invert_predicate) if invert
- predicates = predicates.map(&inverter.method(:call)) if invert
-
  [opts, predicates.inject(&:and), map]
  end
  end
 
  class PredicateBuilder
- def initialize(backend_class)
- @backend_class = backend_class
+ attr_reader :backend_class, :backend_options
+
+ def initialize(attributes)
+ @backend_class = attributes.backend_class
+ @backend_options = attributes.options
+ end
+
+ def build(attr, locale, values, invert)
+ predicate = _build(attr, locale, values)
+ predicate = invert(predicate) if invert
+ predicate
  end
 
- def build(attr, locale, values, backend_options)
- node = @backend_class.build_node(attr, locale, backend_options)
+ private
+
+ def _build(attr, locale, values)
+ node = backend_class.build_node(attr, locale, backend_options)
 
  nils, vals = Array.wrap(collapse(values)).uniq.partition(&:nil?)
  return node.eq(nil) if vals.empty?
 
- vals = vals.map { |val| @backend_class.quote_value(val, backend_options) }
+ vals = vals.map { |val| backend_class.quote_value(val, backend_options) }
 
  predicate = vals.length == 1 ? node.eq(vals.first) : node.in(vals)
  predicate = predicate.or(node.eq(nil)) unless nils.empty?
@@ -112,6 +119,11 @@ def build(attr, locale, values, backend_options)
  def collapse(value)
  value.is_a?(Array) ? value.uniq : value
  end
+
+ # TODO: inline this
+ def invert(predicate)
+ ::ActiveRecord::Relation::WhereClause.new([]).method(:invert_predicate)[predicate]
+ end
  end
 
  private_constant :WhereChain, :ClauseMapper, :PredicateBuilder