Use thread variable instead of fiber variable to store the hub (#1380)

* Use thread variable instead of fiber variable to store the hub

* Update changelog

Author: st0012

sentry-ruby/CHANGELOG.md

@@ -5,6 +5,8 @@
 - Correct type attribute's usages [#1354](https://github.com/getsentry/sentry-ruby/pull/1354)
 - Fix sampling decision precedence [#1335](https://github.com/getsentry/sentry-ruby/pull/1335)
 - Fix set_contexts [#1375](https://github.com/getsentry/sentry-ruby/pull/1375) 
+- Use thread variable instead of fiber variable to store the hub [#1380](https://github.com/getsentry/sentry-ruby/pull/1380)
+  - Fixes [#1374](https://github.com/getsentry/sentry-ruby/issues/1374)
 
 ## 4.3.1
 

sentry-ruby/lib/sentry-ruby.rb

@@ -68,7 +68,7 @@ def init(&block)
       client = Client.new(config)
       scope = Scope.new(max_breadcrumbs: config.max_breadcrumbs)
       hub = Hub.new(client, scope)
-      Thread.current[THREAD_LOCAL] = hub
+      Thread.current.thread_variable_set(THREAD_LOCAL, hub)
       @main_hub = hub
       @background_worker = Sentry::BackgroundWorker.new(config)
     end
@@ -92,7 +92,7 @@ def get_current_hub
       # ideally, we should do this proactively whenever a new thread is created
       # but it's impossible for the SDK to keep track every new thread
       # so we need to use this rather passive way to make sure the app doesn't crash
-      Thread.current[THREAD_LOCAL] || clone_hub_to_current_thread
+      Thread.current.thread_variable_get(THREAD_LOCAL) || clone_hub_to_current_thread
     end
 
     # Returns the current active client.
@@ -107,7 +107,7 @@ def get_current_scope
 
     # Clones the main thread's active hub and stores it to the current thread.
     def clone_hub_to_current_thread
-      Thread.current[THREAD_LOCAL] = get_main_hub.clone
+      Thread.current.thread_variable_set(THREAD_LOCAL, get_main_hub.clone)
     end
 
     # Takes a block and yields the current active scope.

sentry-ruby/spec/sentry_spec.rb

@@ -64,6 +64,18 @@
 
       new_thread.join
     end
+
+    it "stores the hub in a thread variable (instead of just fiber variable)" do
+      Sentry.set_tags(outside_fiber: true)
+
+      fiber = Fiber.new do
+        Sentry.set_tags(inside_fiber: true)
+      end
+
+      fiber.resume
+
+      expect(Sentry.get_current_scope.tags).to eq({ outside_fiber: true, inside_fiber: true })
+    end
   end
 
   describe ".configure_scope" do