Provide friendlier error when async_count is not supported

jdlubrano · jdlubrano · commit 71e7125700c9 · 2024-08-12T10:23:38.000-04:00
diff --git a/lib/active_admin/async_count.rb b/lib/active_admin/async_count.rb
@@ -1,7 +1,11 @@
 # frozen_string_literal: true
 module ActiveAdmin
   class AsyncCount
+    class NotSupportedError < RuntimeError; end
+
     def initialize(collection)
+      raise NotSupportedError, "#{collection.inspect} does not support :async_count" unless collection.respond_to?(:async_count)
+
       @collection = collection.except(:select, :order)
       @promise = @collection.async_count
     end
diff --git a/spec/unit/views/components/scopes_spec.rb b/spec/unit/views/components/scopes_spec.rb
@@ -69,7 +69,7 @@
       end
 
       it "raises an error when ActiveRecord async_count is unavailable", unless: Post.respond_to?(:async_count) do
-        expect { scopes }.to raise_error(NoMethodError, %r{async_count})
+        expect { scopes }.to raise_error(ActiveAdmin::AsyncCount::NotSupportedError, %r{does not support :async_count})
       end
 
       context "when async_count is available in Rails", if: Post.respond_to?(:async_count) do
