Every \`esphome\` CLI invocation pays the cost of whatever \`esphome/__main__.py\`
imports at module scope before the requested command even runs. This
moves three heavy imports into the functions that actually use them:
- \`esphome.zeroconf\` (discover_mdns_devices): only needed for the
name_add_mac_suffix OTA discovery path.
- \`esphome.writer\`: only needed by compile/clean paths.
- \`esphome.yaml_util\`: only needed by codegen, config dump, and rename.
Local measurement drops from ~75ms to ~47ms (-37%) for a cold
\`python -c 'import esphome.__main__'\`. The zeroconf chain alone accounts
for most of the gain — the case that motivated the CI budget check.
Also adds a module-level note explaining the intent so future PRs don't
innocently promote these back to the top.
Retargets four test patches from \`esphome.__main__.discover_mdns_devices\`
to \`esphome.zeroconf.discover_mdns_devices\` now that the symbol is only
bound inside the function that calls it.
- determine-jobs: trigger on changes to requirements_test.txt too; that
file is hashed into the venv cache key and installed during
restore-python, so a change there can alter the import environment.
- ci.yml: merge the --check and --har steps so we only run
importtime-waterfall once per job (was measuring twice: ~7-8s of
wasted CI time per run). Uses the new script/check_import_time.py
--check --har <path> combination; the HAR reflects the same
measurement that produced the pass/fail decision.
- script/check_import_time.py: refactor the CLI so --har is a standalone
option rather than a mutually-exclusive mode. --check and --update
each accept an optional --har PATH that writes the HAR from the same
subprocess invocation. Plain --har is still supported for local use.
- tests: add tests/script/test_check_import_time.py covering HAR parsing,
root lookup, offender ranking/dedup, budget round-trip, and the three
--check exit paths (pass, regression, missing budget) plus the new
--check --har combined write. Add requirements_test.txt case to the
should_run_import_time parametrized test.
The previous parser walked `-X importtime` stderr by hand (string-splitting
on `|`, indent-width math). Replace it with a load of the HAR JSON that
importtime-waterfall already produces: each entry carries the module name,
self-time, and cumulative — no tree reconstruction needed. Drops the
hand-rolled retry loop too, since importtime-waterfall does best-of-6
internally.
The committed budget (75.2ms) was seeded on a fast local machine; GHA
runners measured 122.8ms, so the first CI run tripped the check. Reset
the baseline to 123ms with a 25% margin (ceiling ~154ms) to absorb GHA
variance. Tighten later once we have several data points.
Adds unit tests for should_run_import_time across the trigger matrix and
wires the new mock into the existing test_main_* suite.
After the Phase A / Phase B split in this PR, an external producer that
called wake_loop_threadsafe() (MQTT RX, USB RX, BLE event, espnow,
camera, mWW, speakers, USB host/CDC, lwip socket, enable_loop_soon_any_context)
only got Phase A — the component phase stayed gated by loop_interval_,
so the producer's component loop() could be delayed by up to
loop_interval_ ms before draining its queued work. That breaks the
long-standing semantic of wake_loop_threadsafe().
Add a wake_request flag set by every wake_loop_* entry point and
exchange-cleared at the gate in Application::loop(). When the flag is
set, force Phase B regardless of loop_interval_.
Storage is conditional on the threading model:
- ESPHOME_THREAD_MULTI_ATOMICS: std::atomic<uint8_t> (uint8_t, not
bool, because GCC on Xtensa generates an indirect call for
atomic<bool> ops — same workaround as scheduler.h)
- ESPHOME_THREAD_SINGLE / ESPHOME_THREAD_MULTI_NO_ATOMICS: volatile
uint8_t (8-bit aligned loads/stores are atomic on every supported
MCU; the platform signal that follows wake_request_set provides the
cross-thread/cross-core memory barrier)
Helpers (wake_request_set / wake_request_take) are always_inline so
IRAM_ATTR call sites stay in IRAM. Set BEFORE the platform signal so the
consumer is guaranteed to see the flag on its next gate check.
Adds an integration test that raises loop_interval_ to 2s, snapshots a
counting component's loop count, spawns a std::thread that calls
App.wake_loop_threadsafe() after 50ms, and asserts the count increments
inside a 500ms observation window. Without the fix the count would not
move for ~2s.
- Add unit tests asserting cv.Invalid when `substitutions: !include list.yaml`
resolves to a non-mapping, covering both do_substitution_pass and
do_packages_pass.
- Note in resolve_substitutions_block that the resolve is single-shot and
chained top-level includes are not supported (matches _walk_packages for
`packages: !include`).
J. Nick Koston