Move predicate building to a stand alone PredicateBuilder class

1 files changed, 36 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb
new file mode 100644
index 0000000000..c85a0510b4
--- /dev/null
+++ b/activerecord/lib/active_record/relation/predicate_builder.rb
@@ -0,0 +1,36 @@
+module ActiveRecord
+  class PredicateBuilder
+
+    def initialize(engine)
+      @engine = engine
+    end
+
+    def build_from_hash(attributes, default_table)
+      predicates = attributes.map do |column, value|
+        arel_table = default_table
+
+        if value.is_a?(Hash)
+          arel_table = Arel::Table.new(column, @engine)
+          build_predicate_from_hash(value, arel_table)
+        else
+          column = column.to_s
+
+          if column.include?('.')
+            table_name, column = column.split('.', 2)
+            arel_table = Arel::Table.new(table_name, @engine)
+          end
+
+          case value
+          when Array, Range, ActiveRecord::Associations::AssociationCollection, ActiveRecord::NamedScope::Scope
+            arel_table[column].in(value)
+          else
+            arel_table[column].eq(value)
+          end
+        end
+      end
+
+      predicates.flatten
+    end
+
+  end
+end