adding a join source node

4 files changed, 18 insertions, 29 deletions

diff --git a/lib/arel/visitors/depth_first.rb b/lib/arel/visitors/depth_first.rb
index 49133653c5..9979c8313e 100644
--- a/lib/arel/visitors/depth_first.rb
+++ b/lib/arel/visitors/depth_first.rb
@@ -39,14 +39,6 @@ module Arel
         visit o.distinct
       end
 
-      def join o
-        visit o.left
-        visit o.right
-        visit o.constraint
-      end
-      alias :visit_Arel_Nodes_InnerJoin :join
-      alias :visit_Arel_Nodes_OuterJoin :join
-
       def nary o
         o.children.each { |child| visit child }
       end
@@ -65,6 +57,7 @@ module Arel
       alias :visit_Arel_Nodes_GreaterThan        :binary
       alias :visit_Arel_Nodes_GreaterThanOrEqual :binary
       alias :visit_Arel_Nodes_In                 :binary
+      alias :visit_Arel_Nodes_InnerJoin          :binary
       alias :visit_Arel_Nodes_LessThan           :binary
       alias :visit_Arel_Nodes_LessThanOrEqual    :binary
       alias :visit_Arel_Nodes_Matches            :binary
@@ -72,6 +65,7 @@ module Arel
       alias :visit_Arel_Nodes_NotIn              :binary
       alias :visit_Arel_Nodes_Or                 :binary
       alias :visit_Arel_Nodes_Ordering           :binary
+      alias :visit_Arel_Nodes_OuterJoin          :binary
       alias :visit_Arel_Nodes_StringJoin         :binary
       alias :visit_Arel_Nodes_TableAlias         :binary
       alias :visit_Arel_Nodes_Values             :binary
diff --git a/lib/arel/visitors/dot.rb b/lib/arel/visitors/dot.rb
index 4f80f31421..c525a64a89 100644
--- a/lib/arel/visitors/dot.rb
+++ b/lib/arel/visitors/dot.rb
@@ -36,7 +36,6 @@ module Arel
       def visit_Arel_Nodes_TableAlias o
         visit_edge o, "name"
         visit_edge o, "relation"
-        visit_edge o, "columns"
       end
 
       def visit_Arel_Nodes_Sum o
@@ -90,7 +89,7 @@ module Arel
       end
 
       def visit_Arel_Nodes_SelectCore o
-        visit_edge o, "froms"
+        visit_edge o, "source"
         visit_edge o, "projections"
         visit_edge o, "wheres"
       end
@@ -146,6 +145,7 @@ module Arel
       alias :visit_Arel_Nodes_NotIn              :visit_Arel_Nodes_Equality
       alias :visit_Arel_Nodes_DoesNotMatch       :visit_Arel_Nodes_Equality
       alias :visit_Arel_Nodes_Matches            :visit_Arel_Nodes_Equality
+      alias :visit_Arel_Nodes_JoinSource         :visit_Arel_Nodes_Equality
 
       def visit_String o
         @node_stack.last.fields << o
diff --git a/lib/arel/visitors/join_sql.rb b/lib/arel/visitors/join_sql.rb
index 427f2bb726..8c31934cd0 100644
--- a/lib/arel/visitors/join_sql.rb
+++ b/lib/arel/visitors/join_sql.rb
@@ -12,8 +12,7 @@ module Arel
       private
 
       def visit_Arel_Nodes_SelectCore o
-        return '' unless Nodes::Join === o.from
-        visit o.from
+        o.source.right.map { |j| visit j }.join ' '
       end
 
       def visit_Arel_Nodes_StringJoin o
@@ -22,20 +21,6 @@ module Arel
           visit(o.right)
         ].compact.join ' '
       end
-
-      def visit_Arel_Nodes_OuterJoin o
-        [
-          (visit o.left if Nodes::Join === o.left),
-          "LEFT OUTER JOIN #{visit o.right} #{visit o.constraint if o.constraint}"
-        ].compact.join ' '
-      end
-
-      def visit_Arel_Nodes_InnerJoin o
-        [
-          (visit o.left if Nodes::Join === o.left),
-          "INNER JOIN #{visit o.right} #{visit o.constraint if o.constraint}"
-        ].compact.join ' '
-      end
     end
   end
 end
diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb
index 5767fbae8d..b83bf2f6e7 100644
--- a/lib/arel/visitors/to_sql.rb
+++ b/lib/arel/visitors/to_sql.rb
@@ -127,7 +127,7 @@ module Arel
       def visit_Arel_Nodes_SelectCore o
         [
           "SELECT #{o.projections.map { |x| visit x }.join ', '}",
-          ("FROM #{visit o.from}" if o.from),
+          visit(o.source),
           ("WHERE #{o.wheres.map { |x| visit x }.join ' AND ' }" unless o.wheres.empty?),
           ("GROUP BY #{o.groups.map { |x| visit x }.join ', ' }" unless o.groups.empty?),
           (visit(o.having) if o.having),
@@ -217,16 +217,26 @@ module Arel
         "#{visit o.left} NOT LIKE #{visit o.right}"
       end
 
+      def visit_Arel_Nodes_JoinSource o
+        return unless o.left || !o.right.empty?
+
+        [
+          "FROM",
+          (visit(o.left) if o.left),
+          o.right.map { |j| visit j }.join(' ')
+        ].compact.join ' '
+      end
+
       def visit_Arel_Nodes_StringJoin o
         "#{visit o.left} #{visit o.right}"
       end
 
       def visit_Arel_Nodes_OuterJoin o
-        "#{visit o.left} LEFT OUTER JOIN #{visit o.right} #{visit o.constraint}"
+        "LEFT OUTER JOIN #{visit o.left} #{visit o.right}"
       end
 
       def visit_Arel_Nodes_InnerJoin o
-        "#{visit o.left} INNER JOIN #{visit o.right} #{visit o.constraint if o.constraint}"
+        "INNER JOIN #{visit o.left} #{visit o.right if o.right}"
       end
 
       def visit_Arel_Nodes_On o