Address review: de-vacuous the reject test, loud node overflow, walker logs

- The rejection test registers the hub and matches the extra-keys error,
  so the missing-tracker error can no longer satisfy it vacuously
- register_ble_node logs and drops loudly at capacity: a push_back past
  a StaticVector's bound is a silent no-op, and an undersized slot count
  must show at boot, not as an unresolvable node
- Every walker failure names the failing call and status; the descriptor
  cap gets its own message so a >64-descriptor characteristic is
  diagnosable instead of a permanent silent backoff loop

esphome/components/ble_client/ble_client_gatt.cpp

@@ -14,6 +14,17 @@ static const char *const TAG = "ble_client";
 static const uint32_t FAILURE_HOLD_OFF_STEP_MS = 10000;
 static const uint8_t FAILURE_HOLD_OFF_MAX_STEPS = 6;
 
+void BLEClient::register_ble_node(BLEClientNode *node) {
+  node->set_ble_client_parent(this);
+  if (this->nodes_.size() == ESPHOME_BLE_CLIENT_MAX_NODES) {
+    // push_back past capacity is a silent no-op; an undersized slot count
+    // must be loud at boot, not an unresolvable node at runtime.
+    ESP_LOGE(TAG, "[%s] Node capacity exceeded; node dropped", this->address_str_);
+    return;
+  }
+  this->nodes_.push_back(node);
+}
+
 void BLEClient::set_address(uint64_t address) {
   this->address_ = address;
   uint8_t mac[6];

esphome/components/ble_client/ble_client_gatt.h

@@ -65,10 +65,7 @@ class BLEClient : public Component,
   void set_enabled(bool enabled);
   const char *address_str() const { return this->address_str_; }
 
-  void register_ble_node(BLEClientNode *node) {
-    node->set_ble_client_parent(this);
-    this->nodes_.push_back(node);
-  }
+  void register_ble_node(BLEClientNode *node);
 
   bool connected() const { return this->state_ == State::CONNECTED; }
   bool idle() const { return this->state_ == State::IDLE; }

esphome/components/bluetooth_connection/bluetooth_connection_bluedroid.cpp

@@ -365,16 +365,19 @@ bool BluedroidGattClient::walk_database_(ServiceFn &&on_service, CharFn &&on_cha
   for (uint16_t s = 0; s < this->service_total_; s++) {
     esp_gattc_service_elem_t svc;
     uint16_t svc_count = 1;
-    if (esp_ble_gattc_get_service(this->gattc_if_, this->conn_id_, nullptr, &svc, &svc_count, s) != ESP_GATT_OK ||
-        svc_count == 0) {
+    auto svc_status = esp_ble_gattc_get_service(this->gattc_if_, this->conn_id_, nullptr, &svc, &svc_count, s);
+    if (svc_status != ESP_GATT_OK || svc_count == 0) {
+      this->log_gattc_warning_("esp_ble_gattc_get_service", svc_status);
       return false;
     }
     if (!on_service(s, svc)) {
       return false;
     }
     uint16_t svc_chars = 0;
-    if (esp_ble_gattc_get_attr_count(this->gattc_if_, this->conn_id_, ESP_GATT_DB_CHARACTERISTIC, svc.start_handle,
-                                     svc.end_handle, 0, &svc_chars) != ESP_GATT_OK) {
+    auto count_status = esp_ble_gattc_get_attr_count(this->gattc_if_, this->conn_id_, ESP_GATT_DB_CHARACTERISTIC,
+                                                     svc.start_handle, svc.end_handle, 0, &svc_chars);
+    if (count_status != ESP_GATT_OK) {
+      this->log_gattc_warning_("esp_ble_gattc_get_attr_count", count_status);
       return false;
     }
     for (uint16_t c = 0; c < svc_chars; c++) {
@@ -385,6 +388,7 @@ bool BluedroidGattClient::walk_database_(ServiceFn &&on_service, CharFn &&on_cha
       if (status != ESP_GATT_OK || char_count == 0) {
         // An early terminator contradicts svc_chars from the same cache;
         // never build a silently truncated table.
+        this->log_gattc_warning_("esp_ble_gattc_get_all_char", status);
         return false;
       }
       if (!on_char(svc, chr)) {
@@ -394,6 +398,8 @@ bool BluedroidGattClient::walk_database_(ServiceFn &&on_service, CharFn &&on_cha
         if (d == MAX_DESCRIPTORS_PER_CHARACTERISTIC) {
           // A stack that never reports end-of-range; fail like every other
           // inconsistency instead of truncating the table silently.
+          ESP_LOGW(TAG, "[%d] Descriptor walk exceeded %u entries", this->connection_index_,
+                   MAX_DESCRIPTORS_PER_CHARACTERISTIC);
           return false;
         }
         esp_gattc_descr_elem_t desc;
@@ -404,6 +410,7 @@ bool BluedroidGattClient::walk_database_(ServiceFn &&on_service, CharFn &&on_cha
           break;
         }
         if (desc_status != ESP_GATT_OK || desc_count == 0) {
+          this->log_gattc_warning_("esp_ble_gattc_get_all_descr", desc_status);
           return false;
         }
         if (!on_desc(chr, desc)) {

tests/component_tests/ble_client/test_validation.py

@@ -21,6 +21,7 @@ from esphome.const import (
     CONF_TYPE,
     PlatformFramework,
 )
+from esphome.core import CORE
 from esphome.types import ConfigType
 
 from ..types import SetCoreConfigCallable
@@ -115,10 +116,14 @@ def test_neutral_arm_rejects_esp32_only_keys(
     set_core_config: SetCoreConfigCallable,
 ) -> None:
     # Pins the schema split's rejection side: the legacy-only keys must not
-    # leak into the neutral arm.
-    from esphome.components import ble_client
+    # leak into the neutral arm. The hub is registered so the extra key is
+    # the only error - without it the missing-tracker error would satisfy
+    # the raises vacuously.
+    from esphome.components import ble_client, ble_device_base
 
     set_core_config(PlatformFramework.RP2_ARDUINO)
+    ble_device_base.register_hub_provider("rp2_ble_tracker")
+    CORE.loaded_integrations.add("rp2_ble_tracker")
     for key in ("name", "on_passkey_request", "on_passkey_notification"):
-        with pytest.raises(cv.Invalid):
+        with pytest.raises(cv.Invalid, match="extra keys not allowed"):
             ble_client.CONFIG_SCHEMA({"mac_address": "AA:BB:CC:DD:EE:FF", key: "x"})