From e63428ddce7125318503ebfb40462f823b0bfd56 Mon Sep 17 00:00:00 2001
From: Jonathan Swoboda <154711427+swoboda1337@users.noreply.github.com>
Date: Thu, 24 Sep 2026 17:31:16 +0100
Subject: [PATCH] [nextion] Keep add_waveform_data() available without a
 waveform sensor (#19590)

---
 esphome/components/nextion/nextion.h                      | 2 --
 esphome/components/nextion/nextion_commands.cpp           | 2 --
 tests/components/nextion/common_waveform_lambda.yaml      | 8 ++++++++
 .../nextion/test-waveform-lambda.esp32-idf.yaml           | 3 +++
 4 files changed, 11 insertions(+), 4 deletions(-)
 create mode 100644 tests/components/nextion/common_waveform_lambda.yaml
 create mode 100644 tests/components/nextion/test-waveform-lambda.esp32-idf.yaml

diff --git a/esphome/components/nextion/nextion.h b/esphome/components/nextion/nextion.h
index 6c9c8760f8..320aec048a 100644
--- a/esphome/components/nextion/nextion.h
+++ b/esphome/components/nextion/nextion.h
@@ -614,7 +614,6 @@ class Nextion final : public NextionBase, public PollingComponent, public uart::
    */
   void disable_component_touch(const char *component);
 
-#ifdef USE_NEXTION_WAVEFORM
   /**
    * Add waveform data to a waveform component
    * @param component_id The integer component id.
@@ -624,7 +623,6 @@ class Nextion final : public NextionBase, public PollingComponent, public uart::
   void add_waveform_data(uint8_t component_id, uint8_t channel_number, uint8_t value);
 
   void open_waveform_channel(uint8_t component_id, uint8_t channel_number, uint8_t value);
-#endif  // USE_NEXTION_WAVEFORM
 
   /**
    * Display a picture at coordinates.
diff --git a/esphome/components/nextion/nextion_commands.cpp b/esphome/components/nextion/nextion_commands.cpp
index a356d54e2f..dd3a97065c 100644
--- a/esphome/components/nextion/nextion_commands.cpp
+++ b/esphome/components/nextion/nextion_commands.cpp
@@ -217,7 +217,6 @@ void Nextion::set_component_value(const char *component, int32_t value) {
   this->add_no_result_to_queue_with_printf_(".val", "%s.val=%" PRId32, component, value);
 }
 
-#ifdef USE_NEXTION_WAVEFORM
 void Nextion::add_waveform_data(uint8_t component_id, uint8_t channel_number, uint8_t value) {
   this->add_no_result_to_queue_with_printf_("add", "add %" PRIu8 ",%" PRIu8 ",%" PRIu8, component_id, channel_number,
                                             value);
@@ -227,7 +226,6 @@ void Nextion::open_waveform_channel(uint8_t component_id, uint8_t channel_number
   this->add_no_result_to_queue_with_printf_("addt", "addt %" PRIu8 ",%" PRIu8 ",%" PRIu8, component_id, channel_number,
                                             value);
 }
-#endif  // USE_NEXTION_WAVEFORM
 
 void Nextion::set_component_coordinates(const char *component, uint16_t x, uint16_t y) {
   this->add_no_result_to_queue_with_printf_(".xcen", "%s.xcen=%" PRIu16, component, x);
diff --git a/tests/components/nextion/common_waveform_lambda.yaml b/tests/components/nextion/common_waveform_lambda.yaml
new file mode 100644
index 0000000000..70b1c62d87
--- /dev/null
+++ b/tests/components/nextion/common_waveform_lambda.yaml
@@ -0,0 +1,8 @@
+# Waveform commands from a lambda with no waveform sensor configured, so
+# USE_NEXTION_WAVEFORM is not defined.
+display:
+  - platform: nextion
+    id: main_lcd
+    lambda: |-
+      id(main_lcd).open_waveform_channel(37, 0, 10);
+      id(main_lcd).add_waveform_data(37, 0, 42);
diff --git a/tests/components/nextion/test-waveform-lambda.esp32-idf.yaml b/tests/components/nextion/test-waveform-lambda.esp32-idf.yaml
new file mode 100644
index 0000000000..53535ab6c4
--- /dev/null
+++ b/tests/components/nextion/test-waveform-lambda.esp32-idf.yaml
@@ -0,0 +1,3 @@
+packages:
+  uart: !include ../../test_build_components/common/uart/esp32-idf.yaml
+  waveform_lambda: !include common_waveform_lambda.yaml