From 80fa6efd1e2fd117b2f5ae601fc60fe56b3661ad Mon Sep 17 00:00:00 2001 From: "J. Nick Koston" Date: Mon, 12 Oct 2026 13:44:49 -1000 Subject: [PATCH] [core] Document string tables, shared CRC helpers, NaN sentinels and polling start-up in AGENTS.md (#20599) --- AGENTS.md | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/AGENTS.md b/AGENTS.md index 6bdd9467c0..5031c4a457 100644 --- a/AGENTS.md +++ b/AGENTS.md @@ -202,6 +202,21 @@ file does, and it is the authority when they disagree. The most useful starting `ESPHOME_LOG_TAG(TAG, "name")`, pass status text as `LOG_STR`, e.g. `this->mark_failed(LOG_STR(ESP_LOG_MSG_COMM_FAIL))`, and give an action whose payload is a byte array a `TEMPLATABLE_BYTES` field so a static code stays in flash. + * **Fixed sets of names** (status words, model names): a `PROGMEM_STRING_TABLE` (`esphome/core/progmem.h`), + logged with `get_log_str` and `LOG_STR_ARG`, copied out with `ESPHOME_strncpy_P` before `publish_state`. + A `dump_config` helper that picks a name returns `const LogString *` from `LOG_STR(...)`. + * **CRCs and bit tricks** come from `esphome/core/helpers.h` (`crc8`, `crc16`, `reverse_bits`, `encode_uint16`); + pick the helper's polynomial and bit-order arguments instead of writing a CRC loop. + * **An unset float is `NAN`**, not `optional`; the optional costs 4 to 8 bytes of padding per member. + * **`PollingComponent` first runs `update()`** after a random share of the interval; call `this->update()` at the + end of `setup()` when the entities need a state at boot. + * **A multi-step command sequence** leaves the step pending when the answer is malformed, so the existing + resend and give-up logic handles it; never advance on an answer that was only logged. + * **Entities that each watch a register field:** one class taking register, shift, mask and match from a Python + tuple table, in typed `StaticVector`s sized by `cg.slot_counter`; not a template per bit, not a virtual + listener base (a second vptr per entity). + * **A global feature define** says the code is compiled in, not that this instance uses it: keep the + per-instance check (`if (this->aux_device_ == ...)`) inside the `#ifdef`. * **Failures after `setup()`:** `mark_failed()` is for `setup()` only. A runtime read or write failure sets `status_set_warning()` and the next success clears it; writes skip work when `is_failed()`. * **Fixed platform facts compile to nothing:** gate on `#ifdef USE_ESP8266` and friends, not on a @@ -589,7 +604,9 @@ file does, and it is the authority when they disagree. The most useful starting `script/cpp_unit_test.py `; see `tests/components/README.md`. Set the loop clock in a test with `LoopBlockingGuard{nullptr, nullptr, now_ms}`; the runner resets it before every test. * **Integration tests:** `tests/integration/` runs real firmware on the host. Serial components prove - timeouts and recovery with the `uart_mock` fixture (`tests/integration/test_uart_mock_*.py`). + timeouts and recovery with the `uart_mock` fixture (`tests/integration/test_uart_mock_*.py`). Its + `responses` match on content every time they see it; to answer a repeated request differently, use an + `on_tx` lambda with a static counter and `inject_to_rx_buffer` (see `uart_mock_ld2412_requery_after_giveup.yaml`). * **Keep build-test variants few:** one `test..yaml` per platform the code actually differs on. A variant per board for platform-identical code only adds CI time. * **Component Tests:** YAML-based compilation tests are located in `tests/`. The structure is as follows: