Merge pull request #1226 from mollerhoj/allow_null_always_first_or_last

allow ransack to treat nulls as always first or last

Author: scarroll32

README.md

@@ -278,6 +278,14 @@ Ransack.configure do |c|
 end
 ```
 
+To treat nulls as having the lowest or highest value respectively. To force nulls to always be first or last, use
+
+```rb
+Ransack.configure do |c|
+  c.postgres_fields_sort_option = :nulls_always_first # or :nulls_always_last
+end
+```
+
 See this feature: https://www.postgresql.org/docs/13/queries-order.html
 
 #### Case Insensitive Sorting in PostgreSQL

lib/ransack/adapters/active_record/context.rb

@@ -47,6 +47,10 @@ def evaluate(search, opts = {})
                   scope_or_sort = scope_or_sort.direction == :asc ? Arel.sql("#{scope_or_sort.to_sql} NULLS FIRST") : Arel.sql("#{scope_or_sort.to_sql} NULLS LAST")
                 when :nulls_last
                   scope_or_sort = scope_or_sort.direction == :asc ? Arel.sql("#{scope_or_sort.to_sql} NULLS LAST") : Arel.sql("#{scope_or_sort.to_sql} NULLS FIRST")
+                when :nulls_always_first
+                  scope_or_sort = Arel.sql("#{scope_or_sort.to_sql} NULLS FIRST")
+                when :nulls_always_last
+                  scope_or_sort = Arel.sql("#{scope_or_sort.to_sql} NULLS LAST")
                 end
 
                 relation = relation.order(scope_or_sort)

lib/ransack/configuration.rb

@@ -149,7 +149,7 @@ def sanitize_custom_scope_booleans=(boolean)
     # User may want to configure it like this:
     #
     # Ransack.configure do |c|
-    #   c.postgres_fields_sort_option = :nulls_first # or :nulls_last
+    #   c.postgres_fields_sort_option = :nulls_first # or e.g. :nulls_always_last
     # end
     #
     # See this feature: https://www.postgresql.org/docs/13/queries-order.html

spec/ransack/search_spec.rb

@@ -605,6 +605,18 @@ def remove_quotes_and_backticks(str)
         s = Search.new(Person, s: 'doubled_name desc')
         expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" DESC NULLS FIRST"
 
+        Ransack.configure { |c| c.postgres_fields_sort_option = :nulls_always_first }
+        s = Search.new(Person, s: 'doubled_name asc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" ASC NULLS FIRST"
+        s = Search.new(Person, s: 'doubled_name desc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" DESC NULLS FIRST"
+
+        Ransack.configure { |c| c.postgres_fields_sort_option = :nulls_always_last }
+        s = Search.new(Person, s: 'doubled_name asc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" ASC NULLS LAST"
+        s = Search.new(Person, s: 'doubled_name desc')
+        expect(s.result.to_sql).to eq "SELECT \"people\".* FROM \"people\" ORDER BY \"people\".\"name\" || \"people\".\"name\" DESC NULLS LAST"
+
         Ransack.options = default
       end
     end