From 453ab0adb8ec9f6da7af1d84590e1a2d309711e7 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Mon, 13 Oct 2025 14:10:56 -1000
Subject: [PATCH] backmerge

---
 esphome/core/helpers.h | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index 6b04af3c7c..e838c82f3e 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -180,6 +180,13 @@ template<typename T> class FixedVector {
     }
   }
 
+  // Helper to reset pointers after cleanup
+  void reset_() {
+    data_ = nullptr;
+    capacity_ = 0;
+    size_ = 0;
+  }
+
  public:
   FixedVector() = default;
 
@@ -187,25 +194,19 @@ template<typename T> class FixedVector {
 
   // Enable move semantics for use in containers
   FixedVector(FixedVector &&other) noexcept : data_(other.data_), size_(other.size_), capacity_(other.capacity_) {
-    other.data_ = nullptr;
-    other.size_ = 0;
-    other.capacity_ = 0;
+    other.reset_();
   }
 
   FixedVector &operator=(FixedVector &&other) noexcept {
     if (this != &other) {
       // Delete our current data
-      if (data_ != nullptr) {
-        delete[] data_;
-      }
+      cleanup_();
       // Take ownership of other's data
       data_ = other.data_;
       size_ = other.size_;
       capacity_ = other.capacity_;
       // Leave other in valid empty state
-      other.data_ = nullptr;
-      other.size_ = 0;
-      other.capacity_ = 0;
+      other.reset_();
     }
     return *this;
   }
@@ -213,9 +214,7 @@ template<typename T> class FixedVector {
   // Allocate capacity - can be called multiple times to reinit
   void init(size_t n) {
     cleanup_();
-    data_ = nullptr;
-    capacity_ = 0;
-    size_ = 0;
+    reset_();
     if (n > 0) {
       // Allocate raw memory without calling constructors
       data_ = static_cast<T *>(::operator new(n * sizeof(T)));
@@ -226,6 +225,12 @@ template<typename T> class FixedVector {
   // Clear the vector (reset size to 0, keep capacity)
   void clear() { size_ = 0; }
 
+  // Shrink capacity to fit current size (frees all memory)
+  void shrink_to_fit() {
+    cleanup_();
+    reset_();
+  }
+
   /// Add element without bounds checking
   /// Caller must ensure sufficient capacity was allocated via init()
   /// Silently ignores pushes beyond capacity (no exception or assertion)