Support to_dom_selector for operation selectors (#135)

lib/cable_ready/identifiable.rb

@@ -3,9 +3,13 @@
 module CableReady
   module Identifiable
     def dom_id(record, prefix = nil)
+      return record.to_dom_selector if record.respond_to?(:to_dom_selector)
+
       prefix = prefix.to_s.strip if prefix
 
-      id = if record.is_a?(ActiveRecord::Relation)
+      id = if record.respond_to?(:to_dom_id)
+        record.to_dom_id
+      elsif record.is_a?(ActiveRecord::Relation)
         [prefix, record.model_name.plural].compact.join("_")
       elsif record.is_a?(ActiveRecord::Base)
         ActionView::RecordIdentifier.dom_id(record, prefix)
@@ -15,5 +19,12 @@ def dom_id(record, prefix = nil)
 
       "##{id}".squeeze("#").strip
     end
+
+    def identifiable?(obj)
+      obj.respond_to?(:to_dom_selector) ||
+        obj.respond_to?(:to_dom_id) ||
+        obj.is_a?(ActiveRecord::Relation) ||
+        obj.is_a?(ActiveRecord::Base)
+    end
   end
 end

lib/cable_ready/operation_builder.rb

@@ -32,7 +32,7 @@ def add_operation_method(name)
         options["selector"] = previous_selector if previous_selector && options.exclude?("selector")
         if options.include?("selector")
           @previous_selector = options["selector"]
-          options["selector"] = previous_selector.is_a?(ActiveRecord::Base) || previous_selector.is_a?(ActiveRecord::Relation) ? dom_id(previous_selector) : previous_selector
+          options["selector"] = identifiable?(previous_selector) ? dom_id(previous_selector) : previous_selector
         end
         @enqueued_operations[name.to_s] << options
         self

test/lib/cable_ready/cable_car_test.rb

@@ -25,4 +25,26 @@ class CableReady::CableCarTest < ActiveSupport::TestCase
     CableReady::CableCar.instance.inner_html(selector: "#users", html: "<span>winning</span>").dispatch(clear: false)
     assert_equal({"inner_html" => [{"selector" => "#users", "html" => "<span>winning</span>"}]}, CableReady::CableCar.instance.instance_variable_get(:@enqueued_operations))
   end
+
+  test "selectors should accept any object which respond_to? to_dom_selector" do
+    CableReady::CableCar.instance.reset!
+    my_object = Struct.new(:id) do
+      def to_dom_selector
+        ".#{id}"
+      end
+    end.new("users")
+    dispatch = CableReady::CableCar.instance.inner_html(selector: my_object, html: "<span>winning</span>").dispatch
+    assert_equal({"innerHtml" => [{"selector" => ".users", "html" => "<span>winning</span>"}]}, dispatch)
+  end
+
+  test "selectors should accept any object which respond_to? to_dom_id" do
+    CableReady::CableCar.instance.reset!
+    my_object = Struct.new(:id) do
+      def to_dom_id
+        id
+      end
+    end.new("users")
+    dispatch = CableReady::CableCar.instance.inner_html(selector: my_object, html: "<span>winning</span>").dispatch
+    assert_equal({"innerHtml" => [{"selector" => "#users", "html" => "<span>winning</span>"}]}, dispatch)
+  end
 end