1 files changed, 48 insertions, 0 deletions
diff --git a/activerecord/lib/arel/insert_manager.rb b/activerecord/lib/arel/insert_manager.rb
new file mode 100644
index 0000000000..dcbac6cb43
--- /dev/null
+++ b/activerecord/lib/arel/insert_manager.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+module Arel
+  class InsertManager < Arel::TreeManager
+    def initialize
+      super
+      @ast = Nodes::InsertStatement.new
+    end
+
+    def into table
+      @ast.relation = table
+      self
+    end
+
+    def columns; @ast.columns end
+    def values= val; @ast.values = val; end
+
+    def select select
+      @ast.select = select
+    end
+
+    def insert fields
+      return if fields.empty?
+
+      if String === fields
+        @ast.values = Nodes::SqlLiteral.new(fields)
+      else
+        @ast.relation ||= fields.first.first.relation
+
+        values = []
+
+        fields.each do |column, value|
+          @ast.columns << column
+          values << value
+        end
+        @ast.values = create_values values, @ast.columns
+      end
+      self
+    end
+
+    def create_values values, columns
+      Nodes::Values.new values, columns
+    end
+
+    def create_values_list(rows)
+      Nodes::ValuesList.new(rows)
+    end
+  end
+end