Ransack: "Present" predicate fails with numeric attributes

[ialiendeg]

Using "present" predicate with a numeric field returns an empty array, at least with postgresql database. It seems that the second condition shouldn't be used.

>> SupplierOrder.ransack(work_order_id_present: true).result
  SupplierOrder Load (0.8ms)  SELECT "supplier_orders".* FROM "supplier_orders" WHERE ("supplier_orders"."work_order_id" IS NOT NULL AND "supplier_orders"."work_order_id" != NULL)
=> []

I think the sql should be

SELECT "supplier_orders".* FROM "supplier_orders" WHERE "supplier_orders"."work_order_id" IS NOT NULL

Good work though, this gem is a must :)

[jaredbeck]

I'm seeing the same exact problem with a datetime column.

x != null is a contradiction

[jaredbeck]

Ransack builds the Condition's predicate as follows:

::Banana.arel_table[:created_at].not_eq_all([nil, '']).to_sql
=> "(`bananas`.`created_at` IS NOT NULL AND `bananas`.`created_at` != NULL)"

This implementation is fine for a varchar:

::Banana.arel_table[:color].not_eq_all([nil, '']).to_sql
=> "(`bananas`.`color` IS NOT NULL AND `bananas`.`color` != '')"

As currently implemented, present seems only suited for string-like columns.

@seanfcarroll, should we try to fix present for non-string columns, or should we just note this limitation in the docs?

[gregmolnar]

Let's live with the limitation for now an put this in the backlog.

[jaredbeck]

For posterity, I ended up using the *_not_null predicate instead of *_present.

[benlieb]

@jaredbeck *_not_null on a date field gets:

 undefined method `eq' for #<Arel::Nodes::Equality:0x00007fd5ee4f1cf0>
2.5.3/gems/ransack-2.1.1/lib/ransack/adapters/active_record/context.rb:173:in `build_correlated_subquery'

[prdanelli]

Could I make a suggestion to add something to the docs in the present and `blank sections as this was pretty confusing for a while until i found this bug issue.