Disable ImageExpirationPool during testing (#4363)

* Disable ImageExpirationPool during testing

* Update CHANGELOG.md

---------

Co-authored-by: pajlada <rasmus.karlsson@pajlada.com>

src/messages/Image.hpp

@@ -19,6 +19,14 @@
 #include <memory>
 #include <mutex>
 
+#ifdef CHATTERINO_TEST
+// When running tests, the ImageExpirationPool destructor can be called before
+// all images are deleted, leading to a use-after-free of its mutex. This
+// happens despite the lifetime of the ImageExpirationPool being (apparently)
+// static. Therefore, just disable it during testing.
+#    define DISABLE_IMAGE_EXPIRATION_POOL
+#endif
+
 namespace chatterino {
 namespace detail {
     template <typename Image>
@@ -105,6 +113,8 @@ private:
 // forward-declarable function that calls Image::getEmpty() under the hood.
 ImagePtr getEmptyImagePtr();
 
+#ifndef DISABLE_IMAGE_EXPIRATION_POOL
+
 class ImageExpirationPool
 {
 private:
@@ -131,4 +141,6 @@ private:
     std::mutex mutex_;
 };
 
+#endif
+
 }  // namespace chatterino