1 files changed, 38 insertions, 0 deletions
diff --git a/activerecord/lib/arel/tree_manager.rb b/activerecord/lib/arel/tree_manager.rb
new file mode 100644
index 0000000000..ed47b09a37
--- /dev/null
+++ b/activerecord/lib/arel/tree_manager.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+  class TreeManager
+    include Arel::FactoryMethods
+
+    attr_reader :ast
+
+    def initialize
+      @ctx = nil
+    end
+
+    def to_dot
+      collector = Arel::Collectors::PlainString.new
+      collector = Visitors::Dot.new.accept @ast, collector
+      collector.value
+    end
+
+    def to_sql(engine = Table.engine)
+      collector = Arel::Collectors::SQLString.new
+      collector = engine.connection.visitor.accept @ast, collector
+      collector.value
+    end
+
+    def initialize_copy(other)
+      super
+      @ast = @ast.clone
+    end
+
+    def where(expr)
+      if Arel::TreeManager === expr
+        expr = expr.ast
+      end
+      @ctx.wheres << expr
+      self
+    end
+  end
+end