Update UPGRADING notes regarding return usage and simplify endpoint execution

CHANGELOG.md

@@ -34,6 +34,7 @@
 * [#2594](https://github.com/ruby-grape/grape/pull/2594): Fix routes memoization - [@ericproulx](https://github.com/ericproulx).
 * [#2595](https://github.com/ruby-grape/grape/pull/2595): Keep `within_namespace` as part of our internal api - [@ericproulx](https://github.com/ericproulx).
 * [#2596](https://github.com/ruby-grape/grape/pull/2596): Remove `namespace_reverse_stackable_with_hash` from public scope - [@ericproulx](https://github.com/ericproulx).
+* [#2621](https://github.com/ruby-grape/grape/pull/2621): Update upgrading notes regarding `return` usage and simplify endpoint execution - [@ericproulx](https://github.com/ericproulx).
 * Your contribution here.
 
 ### 2.4.0 (2025-06-18)

UPGRADING.md

@@ -23,7 +23,7 @@ See [#2617](https://github.com/ruby-grape/grape/pull/2617) for more information.
 
 #### Endpoint execution simplified and `return` deprecated
 
-Executing a endpoint's block has been simplified and calling `return` in it has been deprecated.
+Executing a endpoint's block has been simplified and calling `return` in it has been deprecated. Use `next` instead.
 
 See [#2577](https://github.com/ruby-grape/grape/pull/2577) for more information.
 

lib/grape/endpoint.rb

@@ -71,24 +71,10 @@ def initialize(new_settings, options = {}, &block)
 
       @lazy_initialize_lock = Mutex.new
       @lazy_initialized = nil
-      @block = nil
-
       @status = nil
       @stream = nil
       @body = nil
-
-      if block
-        @source = block
-        @block = lambda do |endpoint_instance|
-          ActiveSupport::Notifications.instrument('endpoint_render.grape', endpoint: endpoint_instance) do
-            endpoint_instance.instance_exec(&block)
-          rescue LocalJumpError => e
-            Grape.deprecator.warn 'Using `return` in an endpoint has been deprecated.'
-            return e.exit_value
-          end
-        end
-      end
-
+      @source = block
       @helpers = build_helpers
     end
 
@@ -255,7 +241,14 @@ def run
     end
 
     def execute
-      @block&.call(self)
+      return unless @source
+
+      ActiveSupport::Notifications.instrument('endpoint_render.grape', endpoint: self) do
+        instance_exec(&@source)
+      rescue LocalJumpError => e
+        Grape.deprecator.warn 'Using `return` in an endpoint has been deprecated. Use `next` instead.'
+        return e.exit_value
+      end
     end
 
     def lazy_initialize!

spec/grape/endpoint_spec.rb

@@ -771,16 +771,32 @@ def memoized
     expect(last_response.body).to eq('yo')
   end
 
-  it 'allows explicit return calls' do
-    subject.get('/home') do
-      return 'Hello'
+  context 'when `return`' do
+    it 'calls deprecator' do
+      subject.get('/home') do
+        return 'Hello'
+      end
+
+      expect(Grape.deprecator).to receive(:warn).with('Using `return` in an endpoint has been deprecated. Use `next` instead.')
+
+      get '/home'
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq('Hello')
     end
+  end
 
-    expect(Grape.deprecator).to receive(:warn).with('Using `return` in an endpoint has been deprecated.')
+  context 'when `next`' do
+    it 'does not call deprecator' do
+      subject.get('/home') do
+        next 'Hello'
+      end
 
-    get '/home'
-    expect(last_response.status).to eq(200)
-    expect(last_response.body).to eq('Hello')
+      expect(Grape.deprecator).not_to receive(:warn)
+
+      get '/home'
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq('Hello')
+    end
   end
 
   context 'filters' do