Move the construction of `WhereClause` objects out of `Relation`

Yes, I know, I called it a factory so I'm basically the worst person
ever who loves Java and worships the Gang of Four.

1 files changed, 34 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/relation/where_clause_factory.rb b/activerecord/lib/active_record/relation/where_clause_factory.rb
new file mode 100644
index 0000000000..0430922be3
--- /dev/null
+++ b/activerecord/lib/active_record/relation/where_clause_factory.rb
@@ -0,0 +1,34 @@
+module ActiveRecord
+  class Relation
+    class WhereClauseFactory
+      def initialize(klass, predicate_builder)
+        @klass = klass
+        @predicate_builder = predicate_builder
+      end
+
+      def build(opts, other)
+        binds = []
+
+        case opts
+        when String, Array
+          parts = [klass.send(:sanitize_sql, other.empty? ? opts : ([opts] + other))]
+        when Hash
+          attributes = predicate_builder.resolve_column_aliases(opts)
+          attributes = klass.send(:expand_hash_conditions_for_aggregates, attributes)
+
+          attributes, binds = predicate_builder.create_binds(attributes)
+
+          parts = predicate_builder.build_from_hash(attributes)
+        else
+          parts = [opts]
+        end
+
+        WhereClause.new(parts, binds)
+      end
+
+      protected
+
+      attr_reader :klass, :predicate_builder
+    end
+  end
+end