From 70a9c2f8b6d4408af1b91592af5e77350f3c7335 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Fri, 27 Mar 2026 15:49:57 -1000
Subject: [PATCH] [sensor] Assert size before writing, not after

---
 esphome/components/sensor/filter.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/esphome/components/sensor/filter.h b/esphome/components/sensor/filter.h
index 516b5e7a897..df2b8c0c422 100644
--- a/esphome/components/sensor/filter.h
+++ b/esphome/components/sensor/filter.h
@@ -346,11 +346,11 @@ uint32_t get_loop_component_start_time();
 template<size_t N> class ValueListFilter : public Filter {
  protected:
   explicit ValueListFilter(std::initializer_list<TemplatableValue<float>> values) {
+    ESPHOME_DEBUG_ASSERT(values.size() == N);
     size_t i = 0;
     for (const auto &v : values) {
       this->values_[i++] = v;
     }
-    ESPHOME_DEBUG_ASSERT(i == N);
   }
 
   /// Check if sensor value matches any configured value (with accuracy rounding)