Fix custom validator not ending with _validator (ruby-grape#2337)

* Remove !
Add spec

* Changelog entry

* Update Changelog's entry
Update spec comment
Add spec for anonymous class

* Fix cop

CHANGELOG.md

@@ -13,6 +13,7 @@
 #### Fixes
 
 * [#2328](https://github.com/ruby-grape/grape/pull/2328): Don't cache Class.instance_methods - [@byroot](https://github.com/byroot).
+* [#2337](https://github.com/ruby-grape/grape/pull/2337): Fix: allow custom validators that do not end with _validator - [@ericproulx](https://github.com/ericproulx).
 * Your contribution here.
 
 ## 1.7.1 (2023/05/14)

lib/grape/validations/validators/base.rb

@@ -64,7 +64,7 @@ def validate!(params)
         def self.inherited(klass)
           return if klass.name.blank?
 
-          short_validator_name = klass.name.demodulize.underscore.delete_suffix!('_validator')
+          short_validator_name = klass.name.demodulize.underscore.delete_suffix('_validator')
           Validations.register_validator(short_validator_name, klass)
         end
 

spec/grape/validations/validators/base_spec.rb

@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+RSpec.describe Grape::Validations::Validators::Base do
+  describe '#inherited' do
+    context 'when validator is anonymous' do
+      subject(:custom_validator) { Class.new(described_class) }
+
+      it 'does not register the validator' do
+        expect(Grape::Validations).not_to receive(:register_validator)
+        custom_validator
+      end
+    end
+
+    # Anonymous class does not have a name and class A < B would leak.
+    # Simulates inherited callback
+    context "when validator's underscored name does not end with _validator" do
+      subject(:custom_validator) { described_class.inherited(TestModule::CustomValidatorABC) }
+
+      before { stub_const('TestModule::CustomValidatorABC', Class.new) }
+
+      it 'registers the custom validator with a short name' do
+        expect(Grape::Validations).to receive(:register_validator).with('custom_validator_abc', TestModule::CustomValidatorABC)
+        custom_validator
+      end
+    end
+
+    context "when validator's underscored name ends with _validator" do
+      subject(:custom_validator) { described_class.inherited(TestModule::CustomValidator) }
+
+      before { stub_const('TestModule::CustomValidator', Class.new) }
+
+      it 'registers the custom validator with short name not ending with validator' do
+        expect(Grape::Validations).to receive(:register_validator).with('custom', TestModule::CustomValidator)
+        custom_validator
+      end
+    end
+  end
+end