[remote_base] Keep constant abbwelcome payloads in shared flash tables (#20311)

tests/component_tests/remote_transmitter/config/abbwelcome_payload_tables.yaml

@@ -0,0 +1,36 @@
+---
+esphome:
+  name: test
+  on_boot:
+    then:
+      - remote_transmitter.transmit_abbwelcome:
+          source_address: 0x1234
+          destination_address: 0x5678
+          message_type: 0x01
+          data: [0x10, 0x20, 0x30]
+      - remote_transmitter.transmit_abbwelcome:
+          source_address: 0x1234
+          destination_address: 0x5678
+          message_type: 0x02
+          data: [0x10, 0x20, 0x30]
+      - remote_transmitter.transmit_abbwelcome:
+          source_address: 0x1234
+          destination_address: 0x5678
+          message_type: 0x03
+          data: []
+      - remote_transmitter.transmit_abbwelcome:
+          source_address: 0x1234
+          destination_address: 0x5678
+          message_type: 0x04
+      - remote_transmitter.transmit_abbwelcome:
+          source_address: 0x1234
+          destination_address: 0x5678
+          message_type: 0x05
+          data: !lambda return {0x09};
+
+esp32:
+  board: esp32dev
+
+remote_transmitter:
+  pin: 4
+  carrier_duty_percent: 100%

tests/component_tests/remote_transmitter/test_abbwelcome_payload_tables.py

@@ -0,0 +1,21 @@
+"""Tests for abbwelcome constant data in shared PROGMEM tables."""
+
+from collections.abc import Callable
+from pathlib import Path
+import re
+
+
+def test_constant_data_shares_progmem_tables(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """Equal data shares one table, empty or missing data is an empty table, lambdas stay templates."""
+    main_cpp = generate_main(component_config_path("abbwelcome_payload_tables.yaml"))
+
+    tables = re.findall(
+        r"static constexpr uint8_t (\w+)\[\] PROGMEM = (\{[^}]*\});", main_cpp
+    )
+    assert [v for _, v in tables] == ["{0x10, 0x20, 0x30}"]
+    assert main_cpp.count(f"set_data_static({tables[0][0]}, 3);") == 2
+    assert main_cpp.count("set_data_static(nullptr, 0);") == 2
+    assert main_cpp.count("set_data_template(") == 1