Two gaps remained after the first connection-health commit. A slot retrying into a heap that cannot satisfy its TLS allocation moved no counter at all. disconnect_count rose, but it also rises for dropped live sessions, so it could not separate "actively failing to connect" from "was connected, dropped once". Adds a per-slot connect_failures, incremented in onDisconnect when the event arrives while the client is Starting -- meaning it ended an attempt that never reached onConnect. Late events from a stopped or quarantined client, and soft-disconnects of a live session, are in other states and are not miscounted. A slot parked by the circuit breaker also looked identical to one still retrying, despite being materially worse: the breaker only probes every 30 minutes, so recovery is far slower and an operator may need to intervene. Surfaces both: - `mqttN.diag` gains `cf:<n>` beside the existing `dc:<n>`. - the status payload gains `mqtt_connect_failures` (summed across slots) and `mqtt_slots_breaker` (count of tripped slots), each emitted only when non-zero so a healthy board's payload does not grow. The counter is what distinguishes a retrying slot from a quiet one: while a slot is down its publish counters cannot move by definition, so this is the only value that shows the device is still trying. Both suggested by adversarial review.
Host unit tests
Fast, hardware-free unit tests for the fork's pure logic, run on the host with
GoogleTest via PlatformIO's native environment. They cover the extractable
observer/WebConfig logic (validation, preset table, topic templates, key
parsing) — the parts that don't depend on the ESP32, radio, or network stack.
Integration behavior (AsyncTCP transport, WiFi/MQTT, SoftAP) is exercised
separately; see "Local testing without hardware" in MQTT_IMPLEMENTATION.md.
Running
pio test -e native # all suites
pio test -e native -f test_webconfig_keys # a single suite
A green [PASSED] per suite means GoogleTest returned 0 (all assertions
passed). PlatformIO's "0 test cases" line is just its Unity-style counter and
does not reflect the GoogleTest count — run the built binary directly
(.pio/build/native/program) to see the per-assertion breakdown.
Suites
| Suite | Source under test | Covers |
|---|---|---|
test_mqtt_presets |
src/helpers/MQTTPresets.h |
preset lookup; table integrity (unique names, non-empty URLs, JWT-audience invariant, names fit the slot buffer); mqttPresetNeedsSlotCredentials; slot-count constants |
test_observer_validation |
src/helpers/MQTTObserverValidation.h |
IATA (exactly 3 alphanumerics), owner key (64 hex), NTP hostname, and the buffer-fit check behind the #17 length validation — including boundaries and nulls |
test_webconfig_keys |
src/helpers/WebConfigKeys.h |
POST-key allowlist, secret detection, admin-password classification/validation, slot-index bounds, and the short-key out-of-bounds guard (attacker-supplied keys) |
test_topic_template |
src/helpers/MQTTTopicTemplate.h |
{iata}/{device}/{token}/{type} expansion, overflow/NUL-termination, and a buffer-size fuzz |
test_mqtt_topic_router |
src/helpers/MQTTTopicRouter.h |
complete preset/custom topic-routing contract; MeshRank all types except raw; required identifiers; invalid inputs/slots; exact buffer boundaries |
test_mqtt_connection_policy |
src/helpers/MQTTConnectionPolicy.h |
reconnect guard/backoff/stagger and breaker transitions; stable reset; JWT lifetime/renewal policy; exact timing boundaries and 32-bit millis() rollover; WiFi current-outage start sticky across STA reconnect attempts |
test_network_policy |
src/helpers/NetworkPolicy.h |
transport-neutral MQTT link-transition actions and start ota selected-LAN versus forced/fallback SoftAP choice |
test_network_hostname |
src/helpers/NetworkHostname.h |
DHCP-safe meshcore- hostname generation; invalid-character collapse; empty fallback; exact length boundary; stable identity suffix on truncation |
test_alert_fault_policy |
src/helpers/AlertFaultPolicy.h |
WiFi/MQTT fault edge detector; OutageSnapshot (down / started_ms / initiating reason) fed to tick and formatWifiAlert; reason-8 reconnects change neither duration nor initiating reason; flap between status polls; down at millis()==0; packed 64-bit cross-task word; rate-limit floor and first-fire; 5 s poll cadence and millis() rollover |
test_display_viewport |
src/helpers/ui/DisplayViewport.h, src/helpers/ui/DisplayFrameSignature.h |
logical-to-physical portrait mapping; fractional span coverage; fitted-width conversion; preferred/fallback text scaling; stable visible-frame change detection |
test_mqtt_packet_queue_policy |
src/helpers/MQTTPacketQueuePolicy.h |
queue-full eviction; stale-disconnect flush; adaptive drain limits; bounded QoS0 retries; exact timing boundaries and 32-bit millis() rollover |
test_mqtt_packet_filter |
src/helpers/MQTTPacketFilter.h |
per-slot 0-15 allowlist parsing/formatting, numeric and named spellings; exact bounds; membership; candidate/eligible split and retry-completion policy; pre-queue union gate; default-mask detection |
test_mqtt_runtime_buffer_lifecycle |
src/helpers/MQTTRuntimeBufferLifecycle.h |
idempotent allocation/release; partial-allocation degradation; retry of only missing buffers |
test_mqtt_prefs_codec |
src/helpers/MQTTPrefsStorage.h, src/helpers/MQTTPrefsCodec.h |
binary pre-slot/3-slot/6-slot migration fixtures; v1 header integrity; downgrade preservation; shortest-payload write policy (default filters stay downgrade-readable) |
test_mqtt_prefs_serializer |
src/helpers/MQTTPrefsSerializer.h, src/helpers/ConfigSerializer.* |
semantic nested /mqtt.json round trips; numeric slot keys; required/future version handling; strict length/overflow/duplicate rejection; safe semantic repair; scratch-before-live loading |
test_mqtt_prefs_atomic_store |
src/helpers/MQTTPrefsAtomicStore.h, src/helpers/MQTTPrefsRecovery.h |
production JSON begin/write/checksum-finish/schema-verify/commit orchestration; first-migration and rename-boundary recovery; legacy /node_prefs handoff; failure cleanup and original-file preservation |
test_mqtt_payload_builder |
src/helpers/MQTTPayloadBuilder.cpp |
status/packet/raw JSON contracts; optional fields; escaping; RX metrics and path; score handling; exact buffer bounds; maximum representative payloads |
test_radio_activity_window |
src/helpers/RadioActivityWindow.h |
20-minute minute-bucketed RX window: totals and derived rates; bucket rotation and oldest-to-newest ordering; expiry at the boundary; ring clear after 20 minutes of silence; warm-up versus steady-state denominators; peak minute; last-packet age and staleness; counter saturation; millis() rollover, including the minute boundary a now_ms / 60000 quotient would corrupt |
test_observer_dashboard |
src/helpers/ui/ObserverDashboard.h |
R8 TFT observer dashboard against a recording DisplayDriver in both orientation profiles: compact number/byte/age formatting and the 5 s age quantisation; per-row character budgets; on-panel and inside-the-margin bounds; no silent portrait scale fallback; non-overlapping row rectangles and each row's repaint covering everything it draws; 20-bar graph scaling, ordering and empty/spike cases; per-row signatures and the partial-repaint policy |
test_touch_tap_detector |
src/helpers/ui/TouchTapDetector.h |
debounced rising-edge detection for the polled Expansion Kit touch panel: idle quiet; one tap per touch; long presses do not repeat; sub-debounce blips ignored; contact bounce still counts once; minimum gap between accepted taps; millis() rollover; reset semantics |
test_utils |
src/Utils.cpp |
Utils::toHex (upstream) |
Conventions (and how to add a suite)
- Each
test/test_<name>/directory builds into its own GoogleTest program and must define its ownmain()(::testing::InitGoogleTest+RUN_ALL_TESTS). - Tests are host-only: include only pure headers. Arduino/crypto stubs live
in
test/mocks/(on the include path via-I test/mocks). - Firmware headers are included from
src(via-I src, e.g.#include "helpers/MQTTPresets.h"). Some are guarded or ESP-flavored, so a suite may need shims before the include — e.g.test_mqtt_presetsdoes#define WITH_MQTT_BRIDGE 1(the preset table is behind that flag) and#define PROGMEM(the embedded CA-cert strings are PROGMEM-qualified). - To add a suite: create
test/test_<name>/test_<name>.cppwith amain(), and add any host-only source it links to thenativeenv'sbuild_src_filterinplatformio.ini(header-only code needs no source entry). No other wiring. - Keep logic testable by extracting pure functions into headers (as
MQTTObserverValidation.h/WebConfigKeys.h/MQTTTopicTemplate.hdo) and having the firmware call the same functions.