What is the syntax for referring to named scopes within Squeel?

Question

Is there a way, using Squeel, to refer to already existing scopes?

Consider the following:

scope :continuous, where{ job_type_id == 1 }
scope :standard, where{ job_type_id == 2 }

scope :active, where{ (job_status_id == 2) & ((job_type_id == 1) | ((job_type_id == 2) & (date_start > Time.now) & (date_end < Time.now))) }

All three scopes work properly, but the logic from the first two (continuous and standard) are duplicated within the third, which is what I'd like to avoid, by doing something like:

scope :active, where{ (job_status_id == 2) & (continuous | (standard & (date_start > Time.now) & (date_end < Time.now))) }

... except that I can't find the correct syntax in the Squeel DSL for referring to named scopes.

Is there a way to do what I'd like, or do I just need to be explicit?

Answer 1

Squeel currently doesn't support referencing named scopes. The preferred method is using Squeel sifters and then using the sifters in your scopes:

sifter :continuous { where{ job_type_id == 1 }}
sifter :standard   { where{ job_type_id == 2 }}

scope :continuous, -> { where{ sift(:continuous) }}
scope :standard,   -> { where{ sift(:standard) }}
scope :active,     -> { where{ (job_status_id == 2) & (sift(:continuous) | (sift(:standard) & (date_start > Time.now) & (date_end < Time.now)) }}

Clearly still some repetition, and probably not the best example or use, but just wanted to show how to implement your example with them.

Reference sifters: https://github.com/ernie/squeel#sifters