Added Arel::Nodes::NamedFunction for representing generic SQL functions

3 files changed, 32 insertions, 7 deletions

diff --git a/lib/arel/visitors/depth_first.rb b/lib/arel/visitors/depth_first.rb
index ed95cad472..914b2d1999 100644
--- a/lib/arel/visitors/depth_first.rb
+++ b/lib/arel/visitors/depth_first.rb
@@ -28,6 +28,7 @@ module Arel
       def function o
         visit o.expressions
         visit o.alias
+        visit o.distinct
       end
       alias :visit_Arel_Nodes_Avg    :function
       alias :visit_Arel_Nodes_Exists :function
@@ -35,6 +36,13 @@ module Arel
       alias :visit_Arel_Nodes_Min    :function
       alias :visit_Arel_Nodes_Sum    :function
 
+      def visit_Arel_Nodes_NamedFunction o
+        visit o.name
+        visit o.expressions
+        visit o.distinct
+        visit o.alias
+      end
+
       def visit_Arel_Nodes_Count o
         visit o.expressions
         visit o.alias
diff --git a/lib/arel/visitors/dot.rb b/lib/arel/visitors/dot.rb
index 3c4fe12d1f..92d05c7b67 100644
--- a/lib/arel/visitors/dot.rb
+++ b/lib/arel/visitors/dot.rb
@@ -38,13 +38,6 @@ module Arel
         visit_edge o, "relation"
       end
 
-      def visit_Arel_Nodes_Sum o
-        visit_edge o, "expressions"
-        visit_edge o, "alias"
-      end
-      alias :visit_Arel_Nodes_Max :visit_Arel_Nodes_Sum
-      alias :visit_Arel_Nodes_Avg :visit_Arel_Nodes_Sum
-
       def visit_Arel_Nodes_Count o
         visit_edge o, "expressions"
         visit_edge o, "distinct"
@@ -82,6 +75,24 @@ module Arel
       alias :visit_Arel_Nodes_Top               :unary
       alias :visit_Arel_Nodes_UnqualifiedColumn :unary
 
+      def function o
+        visit_edge o, "expressions"
+        visit_edge o, "distinct"
+        visit_edge o, "alias"
+      end
+      alias :visit_Arel_Nodes_Exists :function
+      alias :visit_Arel_Nodes_Min    :function
+      alias :visit_Arel_Nodes_Max    :function
+      alias :visit_Arel_Nodes_Avg    :function
+      alias :visit_Arel_Nodes_Sum    :function
+
+      def visit_Arel_Nodes_NamedFunction o
+        visit_edge o, "name"
+        visit_edge o, "expressions"
+        visit_edge o, "distinct"
+        visit_edge o, "alias"
+      end
+
       def visit_Arel_Nodes_InsertStatement o
         visit_edge o, "relation"
         visit_edge o, "columns"
diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb
index 4eae5a9ae5..d5534384f8 100644
--- a/lib/arel/visitors/to_sql.rb
+++ b/lib/arel/visitors/to_sql.rb
@@ -183,6 +183,12 @@ eowarn
         visit o.expr
       end
 
+      def visit_Arel_Nodes_NamedFunction o
+        "#{o.name}(#{o.distinct ? 'DISTINCT ' : ''}#{o.expressions.map { |x|
+          visit x
+        }.join(', ')})#{o.alias ? " AS #{visit o.alias}" : ''}"
+      end
+
       def visit_Arel_Nodes_Count o
         "COUNT(#{o.distinct ? 'DISTINCT ' : ''}#{o.expressions.map { |x|
           visit x