Merge remote-tracking branch 'upstream/rp2040-socket-wake' into integration

.github/scripts/codeowners.js

@@ -2,7 +2,7 @@
 //
 // Used by:
 //   - codeowner-review-request.yml
-//   - codeowner-approved-label.yml
+//   - codeowner-approved-label.yml + codeowner-approved-label-update.yml
 //   - auto-label-pr/detectors.js (detectCodeOwner)
 
 /**
@@ -133,11 +133,95 @@ function loadCodeowners(repoRoot = '.') {
   return parseCodeowners(content);
 }
 
+/** Possible label actions returned by determineLabelAction. */
+const LabelAction = Object.freeze({
+  ADD: 'add',
+  REMOVE: 'remove',
+  NONE: 'none',
+});
+
+/**
+ * Determine what label action is needed for a PR based on codeowner approvals.
+ *
+ * Checks changed files against CODEOWNERS patterns, reviews, and current labels
+ * to decide if the label should be added, removed, or left unchanged.
+ *
+ * @param {object} github              - octokit instance from actions/github-script
+ * @param {string} owner               - repo owner
+ * @param {string} repo                - repo name
+ * @param {number} pr_number           - pull request number
+ * @param {Array}  codeownersPatterns   - from loadCodeowners / fetchCodeowners
+ * @param {string} labelName           - label to manage
+ * @returns {Promise<LabelAction>}
+ */
+async function determineLabelAction(github, owner, repo, pr_number, codeownersPatterns, labelName) {
+  // Get the list of changed files in this PR
+  const prFiles = await github.paginate(
+    github.rest.pulls.listFiles,
+    { owner, repo, pull_number: pr_number }
+  );
+
+  const changedFiles = prFiles.map(file => file.filename);
+  console.log(`Found ${changedFiles.length} changed files`);
+
+  if (changedFiles.length === 0) {
+    console.log('No changed files found');
+    return LabelAction.NONE;
+  }
+
+  // Get effective owners using last-match-wins semantics
+  const effective = getEffectiveOwners(changedFiles, codeownersPatterns);
+  const componentCodeowners = effective.users;
+
+  console.log(`Component-specific codeowners: ${Array.from(componentCodeowners).join(', ') || '(none)'}`);
+
+  // Get current labels
+  const { data: currentLabels } = await github.rest.issues.listLabelsOnIssue({
+    owner, repo, issue_number: pr_number
+  });
+  const hasLabel = currentLabels.some(label => label.name === labelName);
+
+  if (componentCodeowners.size === 0) {
+    console.log('No component-specific codeowners found');
+    return hasLabel ? LabelAction.REMOVE : LabelAction.NONE;
+  }
+
+  // Get all reviews and find latest per user
+  const reviews = await github.paginate(
+    github.rest.pulls.listReviews,
+    { owner, repo, pull_number: pr_number }
+  );
+
+  const latestReviewByUser = new Map();
+  for (const review of reviews) {
+    if (!review.user || review.user.type === 'Bot' || review.state === 'COMMENTED') continue;
+    latestReviewByUser.set(review.user.login, review);
+  }
+
+  // Check if any component-specific codeowner has an active approval
+  let hasCodeownerApproval = false;
+  for (const [login, review] of latestReviewByUser) {
+    if (review.state === 'APPROVED' && componentCodeowners.has(login)) {
+      console.log(`Codeowner '${login}' has approved`);
+      hasCodeownerApproval = true;
+      break;
+    }
+  }
+
+  if (hasCodeownerApproval && !hasLabel) return LabelAction.ADD;
+  if (!hasCodeownerApproval && hasLabel) return LabelAction.REMOVE;
+
+  console.log(`Label already ${hasLabel ? 'present' : 'absent'}, no change needed`);
+  return LabelAction.NONE;
+}
+
 module.exports = {
   globToRegex,
   parseCodeowners,
   fetchCodeowners,
   loadCodeowners,
   classifyOwners,
-  getEffectiveOwners
+  getEffectiveOwners,
+  LabelAction,
+  determineLabelAction
 };

.github/workflows/codeowner-approved-label-update.yml

@@ -0,0 +1,95 @@
+# Fallback for fork PRs: phase 1 (codeowner-approved-label.yml) handles
+# non-fork PRs directly but can't write labels on fork PRs (read-only token).
+# This workflow re-determines the action and applies it if needed.
+
+name: Codeowner Approved Label Update
+
+on:
+  workflow_run:
+    workflows: ["Codeowner Approved Label"]
+    types: [completed]
+
+permissions:
+  issues: write
+  pull-requests: read
+  contents: read
+
+jobs:
+  update-label:
+    name: Run
+    if: >
+      github.event.workflow_run.conclusion == 'success' &&
+      github.event.workflow_run.event == 'pull_request_review'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Get PR details
+        id: pr
+        env:
+          GH_TOKEN: ${{ github.token }}
+          HEAD_SHA: ${{ github.event.workflow_run.head_sha }}
+          REPO: ${{ github.repository }}
+        run: |
+          pr_data=$(gh pr list --repo "$REPO" --state open --search "$HEAD_SHA" \
+            --json number,baseRefName --jq '.[0] // empty')
+
+          if [ -z "$pr_data" ]; then
+            echo "No open PR found for SHA $HEAD_SHA, skipping"
+            echo "skip=true" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+
+          pr_number=$(echo "$pr_data" | jq -r '.number')
+          base_ref=$(echo "$pr_data" | jq -r '.baseRefName')
+
+          echo "pr_number=$pr_number" >> "$GITHUB_OUTPUT"
+          echo "base_ref=$base_ref" >> "$GITHUB_OUTPUT"
+          echo "Found PR #$pr_number targeting $base_ref"
+
+      - name: Checkout base repository
+        if: steps.pr.outputs.skip != 'true'
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          repository: ${{ github.repository }}
+          ref: ${{ steps.pr.outputs.base_ref }}
+          sparse-checkout: |
+            .github/scripts/codeowners.js
+            CODEOWNERS
+
+      - name: Update label
+        if: steps.pr.outputs.skip != 'true'
+        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
+        env:
+          PR_NUMBER: ${{ steps.pr.outputs.pr_number }}
+        with:
+          script: |
+            const { loadCodeowners, determineLabelAction, LabelAction } = require('./.github/scripts/codeowners.js');
+
+            const owner = context.repo.owner;
+            const repo = context.repo.repo;
+            const pr_number = parseInt(process.env.PR_NUMBER, 10);
+            const LABEL_NAME = 'code-owner-approved';
+
+            console.log(`Processing PR #${pr_number} for codeowner approval label`);
+
+            const codeownersPatterns = loadCodeowners();
+            const action = await determineLabelAction(
+              github, owner, repo, pr_number, codeownersPatterns, LABEL_NAME
+            );
+
+            if (action === LabelAction.ADD) {
+              await github.rest.issues.addLabels({
+                owner, repo, issue_number: pr_number, labels: [LABEL_NAME]
+              });
+              console.log(`Added '${LABEL_NAME}' label`);
+            } else if (action === LabelAction.REMOVE) {
+              try {
+                await github.rest.issues.removeLabel({
+                  owner, repo, issue_number: pr_number, name: LABEL_NAME
+                });
+                console.log(`Removed '${LABEL_NAME}' label`);
+              } catch (error) {
+                if (error.status !== 404) throw error;
+              }
+            } else {
+              console.log('No label change needed');
+            }

.github/workflows/codeowner-approved-label.yml

@@ -1,9 +1,9 @@
-# This workflow adds/removes a 'code-owner-approved' label when a
-# component-specific codeowner approves (or dismisses) a PR.
-# This helps maintainers prioritize PRs that have codeowner sign-off.
+# Adds/removes a 'code-owner-approved' label when a component-specific
+# codeowner approves (or dismisses) a PR.
 #
-# Only component-specific codeowners count — the catch-all @esphome/core
-# team is excluded so the label reflects domain-expert approval.
+# Handles non-fork PRs directly. For fork PRs the GITHUB_TOKEN is read-only,
+# so label writes are deferred to codeowner-approved-label-update.yml which
+# triggers via workflow_run with write permissions.
 
 name: Codeowner Approved Label
 
@@ -26,134 +26,53 @@ jobs:
         uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           ref: ${{ github.event.pull_request.base.sha }}
+          sparse-checkout: |
+            .github/scripts/codeowners.js
+            CODEOWNERS
 
       - name: Check codeowner approval and update label
         uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
+        env:
+          PR_NUMBER: ${{ github.event.pull_request.number }}
         with:
           script: |
-            const { loadCodeowners, getEffectiveOwners } = require('./.github/scripts/codeowners.js');
+            const { loadCodeowners, determineLabelAction, LabelAction } = require('./.github/scripts/codeowners.js');
 
             const owner = context.repo.owner;
             const repo = context.repo.repo;
-            const pr_number = context.payload.pull_request.number;
+            const pr_number = parseInt(process.env.PR_NUMBER, 10);
             const LABEL_NAME = 'code-owner-approved';
 
             console.log(`Processing PR #${pr_number} for codeowner approval label`);
 
+            const codeownersPatterns = loadCodeowners();
+            const action = await determineLabelAction(
+              github, owner, repo, pr_number, codeownersPatterns, LABEL_NAME
+            );
+
+            if (action === LabelAction.NONE) {
+              console.log('No label change needed');
+              return;
+            }
+
             try {
-              // Get the list of changed files in this PR (with pagination)
-              const prFiles = await github.paginate(
-                github.rest.pulls.listFiles,
-                {
-                  owner,
-                  repo,
-                  pull_number: pr_number
-                }
-              );
-
-              const changedFiles = prFiles.map(file => file.filename);
-              console.log(`Found ${changedFiles.length} changed files`);
-
-              if (changedFiles.length === 0) {
-                console.log('No changed files found, skipping');
-                return;
-              }
-
-              // Parse CODEOWNERS from the checked-out base branch
-              const codeownersPatterns = loadCodeowners();
-
-              // Get effective owners using last-match-wins semantics
-              const effective = getEffectiveOwners(changedFiles, codeownersPatterns);
-
-              // Only keep individual component-specific codeowners (exclude teams)
-              const componentCodeowners = effective.users;
-
-              console.log(`Component-specific codeowners for changed files: ${Array.from(componentCodeowners).join(', ') || '(none)'}`);
-
-              if (componentCodeowners.size === 0) {
-                console.log('No component-specific codeowners found for changed files');
-                // Remove label if present since there are no component codeowners
-                try {
-                  await github.rest.issues.removeLabel({
-                    owner,
-                    repo,
-                    issue_number: pr_number,
-                    name: LABEL_NAME
-                  });
-                  console.log(`Removed '${LABEL_NAME}' label (no component codeowners)`);
-                } catch (error) {
-                  if (error.status !== 404) {
-                    console.log(`Failed to remove label: ${error.message}`);
-                  }
-                }
-                return;
-              }
-
-              // Get all reviews on the PR
-              const reviews = await github.paginate(
-                github.rest.pulls.listReviews,
-                {
-                  owner,
-                  repo,
-                  pull_number: pr_number
-                }
-              );
-
-              // Get the latest review per user (reviews are returned chronologically)
-              const latestReviewByUser = new Map();
-              for (const review of reviews) {
-                // Skip bot reviews and comment-only reviews
-                if (!review.user || review.user.type === 'Bot' || review.state === 'COMMENTED') continue;
-                latestReviewByUser.set(review.user.login, review);
-              }
-
-              // Check if any component-specific codeowner has an active approval
-              let hasCodeownerApproval = false;
-              for (const [login, review] of latestReviewByUser) {
-                if (review.state === 'APPROVED' && componentCodeowners.has(login)) {
-                  console.log(`Codeowner '${login}' has approved`);
-                  hasCodeownerApproval = true;
-                  break;
-                }
-              }
-
-              // Get current labels to check if label is already present
-              const { data: currentLabels } = await github.rest.issues.listLabelsOnIssue({
-                owner,
-                repo,
-                issue_number: pr_number
-              });
-              const hasLabel = currentLabels.some(label => label.name === LABEL_NAME);
-
-              if (hasCodeownerApproval && !hasLabel) {
-                // Add the label
+              if (action === LabelAction.ADD) {
                 await github.rest.issues.addLabels({
-                  owner,
-                  repo,
-                  issue_number: pr_number,
-                  labels: [LABEL_NAME]
+                  owner, repo, issue_number: pr_number, labels: [LABEL_NAME]
                 });
                 console.log(`Added '${LABEL_NAME}' label`);
-              } else if (!hasCodeownerApproval && hasLabel) {
-                // Remove the label
-                try {
-                  await github.rest.issues.removeLabel({
-                    owner,
-                    repo,
-                    issue_number: pr_number,
-                    name: LABEL_NAME
-                  });
-                  console.log(`Removed '${LABEL_NAME}' label`);
-                } catch (error) {
-                  if (error.status !== 404) {
-                    console.log(`Failed to remove label: ${error.message}`);
-                  }
-                }
-              } else {
-                console.log(`Label already ${hasLabel ? 'present' : 'absent'}, no change needed`);
+              } else if (action === LabelAction.REMOVE) {
+                await github.rest.issues.removeLabel({
+                  owner, repo, issue_number: pr_number, name: LABEL_NAME
+                });
+                console.log(`Removed '${LABEL_NAME}' label`);
               }
-
             } catch (error) {
-              console.error(error);
-              core.setFailed(`Failed to process codeowner approval label: ${error.message}`);
+              if (error.status === 403) {
+                console.log('Fork PR: deferring label write to phase 2 workflow');
+              } else if (error.status === 404) {
+                console.log('Label already removed');
+              } else {
+                throw error;
+              }
             }

esphome/components/openthread/openthread.cpp

@@ -1,9 +1,7 @@
 #include "esphome/core/defines.h"
 #ifdef USE_OPENTHREAD
 #include "openthread.h"
-#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 5, 0)
 #include "esp_openthread.h"
-#endif
 
 #include <freertos/portmacro.h>
 
@@ -48,22 +46,15 @@ void OpenThreadComponent::dump_config() {
   }
 }
 
-bool OpenThreadComponent::is_connected() {
-  auto lock = InstanceLock::try_acquire(100);
-  if (!lock) {
-    ESP_LOGW(TAG, "Failed to acquire OpenThread lock in is_connected");
-    return false;
+void OpenThreadComponent::on_state_changed_(otChangedFlags flags, void *context) {
+  if (flags & OT_CHANGED_THREAD_ROLE) {
+    auto *self = static_cast<OpenThreadComponent *>(context);
+    // This runs on the OpenThread task thread with the OT lock held,
+    // so we can safely call otThreadGetDeviceRole directly.
+    otInstance *instance = esp_openthread_get_instance();
+    otDeviceRole role = otThreadGetDeviceRole(instance);
+    self->connected_ = role >= OT_DEVICE_ROLE_CHILD;
   }
-
-  otInstance *instance = lock->get_instance();
-  if (instance == nullptr) {
-    return false;
-  }
-
-  otDeviceRole role = otThreadGetDeviceRole(instance);
-
-  // TODO: If we're a leader, check that there is at least 1 known peer
-  return role >= OT_DEVICE_ROLE_CHILD;
 }
 
 // Gets the off-mesh routable address

esphome/components/openthread/openthread.h

@@ -8,6 +8,7 @@
 
 #include <openthread/srp_client.h>
 #include <openthread/srp_client_buffers.h>
+#include <openthread/instance.h>
 #include <openthread/thread.h>
 
 #include <optional>
@@ -26,7 +27,7 @@ class OpenThreadComponent : public Component {
   bool teardown() override;
   float get_setup_priority() const override { return setup_priority::WIFI; }
 
-  bool is_connected();
+  bool is_connected() const { return this->connected_; }
   network::IPAddresses get_ip_addresses();
   std::optional<otIp6Address> get_omr_address();
   void ot_main();
@@ -42,6 +43,7 @@ class OpenThreadComponent : public Component {
 
  protected:
   std::optional<otIp6Address> get_omr_address_(InstanceLock &lock);
+  static void on_state_changed_(otChangedFlags flags, void *context);
   std::function<void()> factory_reset_external_callback_;
 #if CONFIG_OPENTHREAD_MTD
   uint32_t poll_period_{0};
@@ -49,6 +51,7 @@ class OpenThreadComponent : public Component {
   std::optional<int8_t> output_power_{};
   bool teardown_started_{false};
   bool teardown_complete_{false};
+  bool connected_{false};
 
  private:
   // Stores a pointer to a string literal (static storage duration).

esphome/components/openthread/openthread_esp.cpp

@@ -175,6 +175,9 @@ void OpenThreadComponent::ot_main() {
   // Pass the existing dataset, or NULL which will use the preprocessor definitions
   ESP_ERROR_CHECK(esp_openthread_auto_start(dataset.mLength > 0 ? &dataset : nullptr));
 
+  // Register state change callback to update connected_ reactively instead of polling
+  otSetStateChangedCallback(instance, OpenThreadComponent::on_state_changed_, this);
+
   esp_openthread_launch_mainloop();
 
   // Clean up

esphome/components/packet_transport/packet_transport.cpp

@@ -3,6 +3,8 @@
 #include "esphome/core/helpers.h"
 #include "packet_transport.h"
 
+#include <ranges>
+
 #include "esphome/components/xxtea/xxtea.h"
 
 namespace esphome {
@@ -77,7 +79,7 @@ enum DecodeResult {
   DECODE_EMPTY,
 };
 
-static const size_t MAX_PING_KEYS = 4;
+static constexpr size_t MAX_PING_KEYS = 4;
 
 static inline void add(std::vector<uint8_t> &vec, uint32_t data) {
   vec.push_back(data & 0xFF);
@@ -168,7 +170,7 @@ class PacketDecoder {
     return true;
   }
 
-  bool decrypt(const uint32_t *key) {
+  bool decrypt(const uint32_t *key) const {
     if (this->get_remaining_size() % 4 != 0) {
       return false;
     }
@@ -249,9 +251,9 @@ void PacketTransport::init_data_() {
   } else {
     add(this->data_, DATA_KEY);
   }
-  for (const auto &pkey : this->ping_keys_) {
+  for (auto &value : this->ping_keys_ | std::views::values) {
     add(this->data_, PING_KEY);
-    add(this->data_, pkey.second);
+    add(this->data_, value);
   }
 }
 
@@ -331,7 +333,7 @@ void PacketTransport::update() {
   auto now = millis() / 1000;
   if (this->last_key_time_ + this->ping_pong_recyle_time_ < now) {
     this->resend_ping_key_ = this->ping_pong_enable_;
-    ESP_LOGV(TAG, "Ping request, age %u", now - this->last_key_time_);
+    ESP_LOGV(TAG, "Ping request, age %" PRIu32, now - this->last_key_time_);
     this->last_key_time_ = now;
   }
   for (const auto &provider : this->providers_) {
@@ -339,24 +341,32 @@ void PacketTransport::update() {
     if (key_response_age > (this->ping_pong_recyle_time_ * 2u)) {
 #ifdef USE_STATUS_SENSOR
       if (provider.second.status_sensor != nullptr && provider.second.status_sensor->state) {
-        ESP_LOGI(TAG, "Ping status for %s timeout at %u with age %u", provider.first.c_str(), now, key_response_age);
+        ESP_LOGI(TAG, "Ping status for %s timeout at %" PRIu32 " with age %" PRIu32, provider.first.c_str(), now,
+                 key_response_age);
         provider.second.status_sensor->publish_state(false);
       }
 #endif
 #ifdef USE_SENSOR
-      for (auto &sensor : this->remote_sensors_[provider.first]) {
-        sensor.second->publish_state(NAN);
+      auto it = this->remote_sensors_.find(provider.first);
+      if (it != this->remote_sensors_.end()) {
+        for (auto &val : it->second | std::views::values) {
+          val->publish_state(NAN);
+        }
       }
 #endif
 #ifdef USE_BINARY_SENSOR
-      for (auto &sensor : this->remote_binary_sensors_[provider.first]) {
-        sensor.second->invalidate_state();
+      auto bs_it = this->remote_binary_sensors_.find(provider.first);
+      if (bs_it != this->remote_binary_sensors_.end()) {
+        for (auto &val : bs_it->second | std::views::values) {
+          val->invalidate_state();
+        }
       }
 #endif
     } else {
 #ifdef USE_STATUS_SENSOR
       if (provider.second.status_sensor != nullptr && !provider.second.status_sensor->state) {
-        ESP_LOGI(TAG, "Ping status for %s restored at %u with age %u", provider.first.c_str(), now, key_response_age);
+        ESP_LOGI(TAG, "Ping status for %s restored at %" PRIu32 " with age %" PRIu32, provider.first.c_str(), now,
+                 key_response_age);
         provider.second.status_sensor->publish_state(true);
       }
 #endif
@@ -367,11 +377,16 @@ void PacketTransport::update() {
 void PacketTransport::add_key_(const char *name, uint32_t key) {
   if (!this->is_encrypted_())
     return;
-  if (this->ping_keys_.count(name) == 0 && this->ping_keys_.size() == MAX_PING_KEYS) {
-    ESP_LOGW(TAG, "Ping key from %s discarded", name);
-    return;
+  auto it = this->ping_keys_.find(name);
+  if (it == this->ping_keys_.end()) {
+    if (this->ping_keys_.size() == MAX_PING_KEYS) {
+      ESP_LOGW(TAG, "Ping key from %s discarded", name);
+      return;
+    }
+    this->ping_keys_.emplace(name, key);  // allocates string key once only
+  } else {
+    it->second = key;  // key string already exists in map, no allocation
   }
-  this->ping_keys_[name] = key;
   this->updated_ = true;
   ESP_LOGV(TAG, "Ping key from %s now %X", name, (unsigned) key);
 }
@@ -431,17 +446,19 @@ void PacketTransport::process_(std::span<const uint8_t> data) {
     return;
   }
 
-  if (this->providers_.count(namebuf) == 0) {
+  auto it = this->providers_.find(namebuf);
+  if (it == this->providers_.end()) {
     ESP_LOGVV(TAG, "Unknown hostname %s", namebuf);
     return;
   }
+  auto &provider = it->second;
   ESP_LOGV(TAG, "Found hostname %s", namebuf);
 
 #ifdef USE_SENSOR
-  auto &sensors = this->remote_sensors_[namebuf];
+  auto &sensors = this->remote_sensors_.try_emplace(namebuf).first->second;
 #endif
 #ifdef USE_BINARY_SENSOR
-  auto &binary_sensors = this->remote_binary_sensors_[namebuf];
+  auto &binary_sensors = this->remote_binary_sensors_.try_emplace(namebuf).first->second;
 #endif
 
   if (!decoder.bump_to(4)) {
@@ -453,7 +470,6 @@ void PacketTransport::process_(std::span<const uint8_t> data) {
     return;
   }
 
-  auto &provider = this->providers_[namebuf];
   // if encryption not used with this host, ping check is pointless since it would be easily spoofed.
   if (provider.encryption_key.empty())
     ping_key_seen = true;
@@ -495,16 +511,19 @@ void PacketTransport::process_(std::span<const uint8_t> data) {
     if (decoder.decode(BINARY_SENSOR_KEY, namebuf, sizeof(namebuf), byte) == DECODE_OK) {
       ESP_LOGV(TAG, "Got binary sensor %s %d", namebuf, byte);
 #ifdef USE_BINARY_SENSOR
-      if (binary_sensors.count(namebuf) != 0)
-        binary_sensors[namebuf]->publish_state(byte != 0);
+      auto bs = binary_sensors.find(namebuf);
+      if (bs != binary_sensors.end()) {
+        bs->second->publish_state(byte != 0);
+      }
 #endif
       continue;
     }
     if (decoder.decode(SENSOR_KEY, namebuf, sizeof(namebuf), rdata.u32) == DECODE_OK) {
       ESP_LOGV(TAG, "Got sensor %s %f", namebuf, rdata.f32);
 #ifdef USE_SENSOR
-      if (sensors.count(namebuf) != 0)
-        sensors[namebuf]->publish_state(rdata.f32);
+      auto sensor_it = sensors.find(namebuf);
+      if (sensor_it != sensors.end())
+        sensor_it->second->publish_state(rdata.f32);
 #endif
       continue;
     }
@@ -537,12 +556,18 @@ void PacketTransport::dump_config() {
     ESP_LOGCONFIG(TAG, "  Remote host: %s", host.first.c_str());
     ESP_LOGCONFIG(TAG, "    Encrypted: %s", YESNO(!host.second.encryption_key.empty()));
 #ifdef USE_SENSOR
-    for (const auto &sensor : this->remote_sensors_[host.first.c_str()])
-      ESP_LOGCONFIG(TAG, "    Sensor: %s", sensor.first.c_str());
+    auto rs = this->remote_sensors_.find(host.first.c_str());
+    if (rs != this->remote_sensors_.end()) {
+      for (const auto &key : rs->second | std::views::keys)
+        ESP_LOGCONFIG(TAG, "    Sensor: %s", key.c_str());
+    }
 #endif
 #ifdef USE_BINARY_SENSOR
-    for (const auto &sensor : this->remote_binary_sensors_[host.first.c_str()])
-      ESP_LOGCONFIG(TAG, "    Binary Sensor: %s", sensor.first.c_str());
+    auto rbs = this->remote_binary_sensors_.find(host.first.c_str());
+    if (rbs != this->remote_binary_sensors_.end()) {
+      for (const auto &key : rbs->second | std::views::keys)
+        ESP_LOGCONFIG(TAG, "    Binary Sensor: %s", key.c_str());
+    }
 #endif
   }
 }

esphome/components/packet_transport/packet_transport.h

@@ -24,6 +24,9 @@
 namespace esphome {
 namespace packet_transport {
 
+// std::less provides allocation-free comparison with const char *
+template<typename T> using string_map_t = std::map<std::string, T, std::less<>>;
+
 struct Provider {
   std::vector<uint8_t> encryption_key;
   const char *name;
@@ -79,15 +82,15 @@ class PacketTransport : public PollingComponent {
 #endif
 
   void add_provider(const char *hostname) {
-    if (this->providers_.count(hostname) == 0) {
+    if (!this->providers_.contains(hostname)) {
       Provider provider{};
       provider.name = hostname;
       this->providers_[hostname] = provider;
 #ifdef USE_SENSOR
-      this->remote_sensors_[hostname] = std::map<std::string, sensor::Sensor *>();
+      this->remote_sensors_[hostname] = string_map_t<sensor::Sensor *>();
 #endif
 #ifdef USE_BINARY_SENSOR
-      this->remote_binary_sensors_[hostname] = std::map<std::string, binary_sensor::BinarySensor *>();
+      this->remote_binary_sensors_[hostname] = string_map_t<binary_sensor::BinarySensor *>();
 #endif
     }
   }
@@ -139,23 +142,23 @@ class PacketTransport : public PollingComponent {
 
 #ifdef USE_SENSOR
   std::vector<Sensor> sensors_{};
-  std::map<std::string, std::map<std::string, sensor::Sensor *>> remote_sensors_{};
+  string_map_t<string_map_t<sensor::Sensor *>> remote_sensors_{};
 #endif
 #ifdef USE_BINARY_SENSOR
   std::vector<BinarySensor> binary_sensors_{};
-  std::map<std::string, std::map<std::string, binary_sensor::BinarySensor *>> remote_binary_sensors_{};
+  string_map_t<string_map_t<binary_sensor::BinarySensor *>> remote_binary_sensors_{};
 #endif
 
-  std::map<std::string, Provider> providers_{};
+  string_map_t<Provider> providers_{};
   std::vector<uint8_t> ping_header_{};
   std::vector<uint8_t> header_{};
   std::vector<uint8_t> data_{};
-  std::map<std::string, uint32_t> ping_keys_{};
+  string_map_t<uint32_t> ping_keys_{};
   const char *platform_name_{""};
   void add_key_(const char *name, uint32_t key);
   void send_ping_pong_request_();
 
-  inline bool is_encrypted_() { return !this->encryption_key_.empty(); }
+  bool is_encrypted_() const { return !this->encryption_key_.empty(); }
 };
 
 }  // namespace packet_transport

esphome/components/socket/lwip_raw_tcp_impl.cpp

@@ -11,6 +11,9 @@
 
 #ifdef USE_ESP8266
 #include <coredecls.h>  // For esp_schedule()
+#elif defined(USE_RP2040)
+#include <hardware/sync.h>  // For __sev(), __wfe()
+#include <pico/time.h>      // For add_alarm_in_ms(), cancel_alarm()
 #endif
 
 namespace esphome::socket {
@@ -40,6 +43,59 @@ void IRAM_ATTR socket_wake() {
   s_socket_woke = true;
   esp_schedule();
 }
+#elif defined(USE_RP2040)
+// RP2040 (non-FreeRTOS) socket wake using hardware WFE/SEV instructions.
+//
+// Same pattern as ESP8266's esp_delay()/esp_schedule(): set a one-shot timer,
+// then sleep with __wfe(). Wake on either:
+//   - Timer alarm fires → callback calls __sev() → __wfe() returns → timeout
+//   - Socket data arrives → LWIP callback calls socket_wake() → __sev() → __wfe() returns → early wake
+//
+// CYW43 WiFi chip communicates via SPI interrupts on core 0. When data arrives,
+// the GPIO interrupt fires → async_context pendsv processes CYW43/LWIP → recv/accept
+// callbacks call socket_wake() → __sev() wakes the main loop from __wfe() sleep.
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+static volatile bool s_socket_woke = false;
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+static volatile bool s_delay_expired = false;
+
+static int64_t alarm_callback(alarm_id_t id, void *user_data) {
+  (void) id;
+  (void) user_data;
+  s_delay_expired = true;
+  // Wake the main loop from __wfe() sleep — timeout expired.
+  __sev();
+  // Return 0 = don't reschedule (one-shot)
+  return 0;
+}
+
+void socket_delay(uint32_t ms) {
+  if (ms == 0)
+    return;
+  s_socket_woke = false;
+  s_delay_expired = false;
+  // Set a one-shot timer to wake us after the timeout.
+  // add_alarm_in_ms returns >0 on success, 0 if time already passed, <0 on error.
+  alarm_id_t alarm = add_alarm_in_ms(ms, alarm_callback, nullptr, true);
+  if (alarm <= 0)
+    return;  // Timer already fired or no alarm slots available
+  // Sleep until woken by either the timer alarm or socket_wake().
+  // __wfe() may return spuriously (stale event register, other interrupts),
+  // so we loop checking both flags.
+  while (!s_socket_woke && !s_delay_expired) {
+    __wfe();
+  }
+  // Cancel timer if we woke early (socket data arrived before timeout)
+  if (!s_delay_expired)
+    cancel_alarm(alarm);
+}
+
+void socket_wake() {
+  s_socket_woke = true;
+  // Wake the main loop from __wfe() sleep. __sev() is a global event that
+  // wakes any core sleeping in __wfe(). This is ISR-safe.
+  __sev();
+}
 #endif
 
 static const char *const TAG = "socket.lwip";
@@ -371,7 +427,7 @@ err_t LWIPRawImpl::recv_fn(struct pbuf *pb, err_t err) {
   } else {
     pbuf_cat(this->rx_buf_, pb);
   }
-#ifdef USE_ESP8266
+#if (defined(USE_ESP8266) || defined(USE_RP2040))
   // Wake the main loop immediately so it can process the received data.
   socket_wake();
 #endif
@@ -650,7 +706,7 @@ err_t LWIPRawListenImpl::accept_fn_(struct tcp_pcb *newpcb, err_t err) {
   sock->init();
   this->accepted_sockets_[this->accepted_socket_count_++] = std::move(sock);
   LWIP_LOG("Accepted connection, queue size: %d", this->accepted_socket_count_);
-#ifdef USE_ESP8266
+#if (defined(USE_ESP8266) || defined(USE_RP2040))
   // Wake the main loop immediately so it can accept the new connection.
   socket_wake();
 #endif

esphome/components/socket/socket.h

@@ -120,13 +120,17 @@ socklen_t set_sockaddr_any(struct sockaddr *addr, socklen_t addrlen, uint16_t po
 /// Format sockaddr into caller-provided buffer, returns length written (excluding null)
 size_t format_sockaddr_to(const struct sockaddr *addr_ptr, socklen_t len, std::span<char, SOCKADDR_STR_LEN> buf);
 
-#if defined(USE_ESP8266) && defined(USE_SOCKET_IMPL_LWIP_TCP)
+#if (defined(USE_ESP8266) || defined(USE_RP2040)) && defined(USE_SOCKET_IMPL_LWIP_TCP)
 /// Delay that can be woken early by socket activity.
-/// On ESP8266, lwip callbacks set a flag and call esp_schedule() to wake the delay.
+/// On ESP8266, uses esp_delay() with a callback that checks socket activity.
+/// On RP2040, uses __wfe() (Wait For Event) to truly sleep until an interrupt
+/// (CYW43 GPIO, timer alarm) fires, then processes pending async_context work.
 void socket_delay(uint32_t ms);
 
-/// Signal socket/IO activity and wake the main loop from esp_delay() early.
-/// ISR-safe: uses IRAM_ATTR internally and only sets a volatile flag + esp_schedule().
+/// Signal socket/IO activity and wake the main loop early.
+/// On ESP8266: sets flag + esp_schedule().
+/// On RP2040: sets flag + __sev() (Send Event) to wake from __wfe().
+/// ISR-safe on both platforms.
 void socket_wake();  // NOLINT(readability-redundant-declaration)
 #endif
 

esphome/core/application.cpp

@@ -35,7 +35,7 @@
 #include "esphome/components/setup_heap_stats/setup_heap_stats.h"
 #endif
 
-#if defined(USE_ESP8266) && defined(USE_SOCKET_IMPL_LWIP_TCP)
+#if (defined(USE_ESP8266) || defined(USE_RP2040)) && defined(USE_SOCKET_IMPL_LWIP_TCP)
 #include "esphome/components/socket/socket.h"
 #endif
 
@@ -730,8 +730,10 @@ void Application::yield_with_select_(uint32_t delay_ms) {
   }
   // No sockets registered or select() failed - use regular delay
   delay(delay_ms);
-#elif defined(USE_ESP8266) && defined(USE_SOCKET_IMPL_LWIP_TCP)
-  // No select support but can wake on socket activity via esp_schedule()
+#elif (defined(USE_ESP8266) || defined(USE_RP2040)) && defined(USE_SOCKET_IMPL_LWIP_TCP)
+  // No select support but can wake on socket activity
+  // ESP8266: via esp_schedule()
+  // RP2040: via __sev()/__wfe() hardware sleep/wake
   socket::socket_delay(delay_ms);
 #else
   // No select support, use regular delay

script/cpp_unit_test.py

@@ -12,6 +12,7 @@ from esphome.__main__ import command_compile, parse_args
 from esphome.config import validate_config
 from esphome.core import CORE
 from esphome.platformio_api import get_idedata
+from esphome.yaml_util import load_yaml
 
 # This must coincide with the version in /platformio.ini
 PLATFORMIO_GOOGLE_TEST_LIB = "google/googletest@^1.15.2"
@@ -44,6 +45,38 @@ def filter_components_without_tests(components: list[str]) -> list[str]:
     return filtered_components
 
 
+# Name of optional per-component YAML config merged into the test build
+# before validation so that platform defines (USE_SENSOR, etc.) are generated.
+CPP_TEST_CONFIG_FILE = "cpp_test.yaml"
+
+
+def load_component_test_configs(components: list[str]) -> dict:
+    """Load cpp_test.yaml files from test component directories.
+
+    These configs are merged into the base test config *before* validation
+    so that entity registration runs during code generation, which causes
+    the corresponding USE_* defines to be emitted.
+    """
+    merged: dict = {}
+    for component in components:
+        config_file = COMPONENTS_TESTS_DIR / component / CPP_TEST_CONFIG_FILE
+        if not config_file.exists():
+            continue
+        component_config = load_yaml(config_file)
+        if not component_config:
+            continue
+        for key, value in component_config.items():
+            if (
+                key in merged
+                and isinstance(merged[key], list)
+                and isinstance(value, list)
+            ):
+                merged[key].extend(value)
+            else:
+                merged[key] = value
+    return merged
+
+
 def create_test_config(config_name: str, includes: list[str]) -> dict:
     """Create ESPHome test configuration for C++ unit tests.
 
@@ -115,6 +148,11 @@ def run_tests(selected_components: list[str]) -> int:
 
     config = create_test_config(config_name, includes)
 
+    # Merge component-specific test configs (e.g. sensor instances) before
+    # validation so that entity registration and USE_* defines work.
+    extra_config = load_component_test_configs(components)
+    config.update(extra_config)
+
     CORE.config_path = COMPONENTS_TESTS_DIR / "dummy.yaml"
     CORE.dashboard = None
 
@@ -122,8 +160,10 @@ def run_tests(selected_components: list[str]) -> int:
     config = validate_config(config, {})
 
     # Add all components and dependencies to the base configuration after validation, so their files
-    # are added to the build.
-    config.update({key: {} for key in components_with_dependencies})
+    # are added to the build.  Use setdefault to avoid overwriting entries that were
+    # already validated (e.g. sensor instances from cpp_test.yaml).
+    for key in components_with_dependencies:
+        config.setdefault(key, {})
 
     print(f"Testing components: {', '.join(components)}")
     CORE.config = config

tests/components/packet_transport/common.h

@@ -0,0 +1,98 @@
+#pragma once
+#include <cstdint>
+#include <cstring>
+#include <cstdio>
+#include <vector>
+#include <gtest/gtest.h>
+#include "esphome/components/packet_transport/packet_transport.h"
+
+namespace esphome::packet_transport::testing {
+
+// Protocol constants mirrored from packet_transport.cpp for test packet construction.
+static constexpr uint16_t MAGIC_NUMBER = 0x4553;
+static constexpr uint16_t MAGIC_PING = 0x5048;
+
+// Concrete testable implementation of PacketTransport.
+// Captures sent packets and exposes protected members for verification.
+//
+// Sensor round-trip tests require USE_SENSOR / USE_BINARY_SENSOR to be defined,
+// which happens when 'sensor' and 'binary_sensor' components are in the build.
+// Run with --all or include those components to enable the full test suite.
+class TestablePacketTransport : public PacketTransport {
+ public:
+  using PacketTransport::add_key_;
+  using PacketTransport::data_;
+  using PacketTransport::encryption_key_;
+  using PacketTransport::flush_;
+  using PacketTransport::header_;
+  using PacketTransport::increment_code_;
+  using PacketTransport::init_data_;
+  using PacketTransport::is_encrypted_;
+  using PacketTransport::is_provider_;
+  using PacketTransport::name_;
+  using PacketTransport::ping_key_;
+  using PacketTransport::ping_keys_;
+  using PacketTransport::ping_pong_enable_;
+  using PacketTransport::ping_pong_recyle_time_;
+  using PacketTransport::process_;
+  using PacketTransport::providers_;
+  using PacketTransport::rolling_code_;
+  using PacketTransport::rolling_code_enable_;
+  using PacketTransport::send_data_;
+  using PacketTransport::updated_;
+#ifdef USE_SENSOR
+  using PacketTransport::add_data_;
+  using PacketTransport::remote_sensors_;
+  using PacketTransport::sensors_;
+#endif
+#ifdef USE_BINARY_SENSOR
+  using PacketTransport::add_binary_data_;
+  using PacketTransport::binary_sensors_;
+  using PacketTransport::remote_binary_sensors_;
+#endif
+
+  // NOTE: std::vector is used here for test convenience. For production code,
+  // consider using StaticVector or FixedVector from esphome/core/helpers.h instead.
+  mutable std::vector<std::vector<uint8_t>> sent_packets;
+  size_t max_packet_size{512};
+  bool send_enabled{true};
+
+  void send_packet(const std::vector<uint8_t> &buf) const override { this->sent_packets.push_back(buf); }
+  size_t get_max_packet_size() override { return this->max_packet_size; }
+  bool should_send() override { return this->send_enabled; }
+
+  /// Build the packet header for testing without requiring App or global_preferences.
+  void init_for_test(const char *name) {
+    this->name_ = name;
+    this->header_.clear();
+    // MAGIC_NUMBER as uint16_t little-endian
+    this->header_.push_back(MAGIC_NUMBER & 0xFF);
+    this->header_.push_back((MAGIC_NUMBER >> 8) & 0xFF);
+    // Length-prefixed hostname
+    auto len = strlen(name);
+    this->header_.push_back(static_cast<uint8_t>(len));
+    for (size_t i = 0; i < len; i++)
+      this->header_.push_back(name[i]);
+    // Pad to 4-byte boundary
+    while (this->header_.size() & 0x3)
+      this->header_.push_back(0);
+  }
+};
+
+/// Build a MAGIC_PING packet for testing add_key_ / ping-pong flows.
+inline std::vector<uint8_t> build_ping_packet(const char *hostname, uint32_t key) {
+  std::vector<uint8_t> packet;
+  packet.push_back(MAGIC_PING & 0xFF);
+  packet.push_back((MAGIC_PING >> 8) & 0xFF);
+  auto len = strlen(hostname);
+  packet.push_back(static_cast<uint8_t>(len));
+  for (size_t i = 0; i < len; i++)
+    packet.push_back(hostname[i]);
+  packet.push_back(key & 0xFF);
+  packet.push_back((key >> 8) & 0xFF);
+  packet.push_back((key >> 16) & 0xFF);
+  packet.push_back((key >> 24) & 0xFF);
+  return packet;
+}
+
+}  // namespace esphome::packet_transport::testing

tests/components/packet_transport/cpp_test.yaml

@@ -0,0 +1,11 @@
+# Extra component configuration required by C++ unit tests.
+# Loaded by cpp_unit_test.py and merged into the test build config
+# before validation, so that platform defines (USE_SENSOR, etc.) are generated.
+
+sensor:
+  - platform: template
+    id: test_cpp_sensor
+
+binary_sensor:
+  - platform: template
+    id: test_cpp_binary_sensor

tests/components/packet_transport/packet_transport_test.cpp

@@ -0,0 +1,445 @@
+#include "common.h"
+
+namespace esphome::packet_transport::testing {
+
+// --- Configuration setter tests ---
+
+TEST(PacketTransportTest, SetIsProvider) {
+  TestablePacketTransport transport;
+  transport.set_is_provider(true);
+  EXPECT_TRUE(transport.is_provider_);
+}
+
+TEST(PacketTransportTest, SetEncryptionKey) {
+  TestablePacketTransport transport;
+  std::vector<uint8_t> key(32, 0xAB);
+  transport.set_encryption_key(key);
+  EXPECT_EQ(transport.encryption_key_, key);
+  EXPECT_TRUE(transport.is_encrypted_());
+}
+
+TEST(PacketTransportTest, NoEncryptionByDefault) {
+  TestablePacketTransport transport;
+  EXPECT_FALSE(transport.is_encrypted_());
+}
+
+TEST(PacketTransportTest, SetRollingCodeEnable) {
+  TestablePacketTransport transport;
+  transport.set_rolling_code_enable(true);
+  EXPECT_TRUE(transport.rolling_code_enable_);
+}
+
+TEST(PacketTransportTest, SetPingPongEnable) {
+  TestablePacketTransport transport;
+  transport.set_ping_pong_enable(true);
+  EXPECT_TRUE(transport.ping_pong_enable_);
+}
+
+TEST(PacketTransportTest, SetPingPongRecycleTime) {
+  TestablePacketTransport transport;
+  transport.set_ping_pong_recycle_time(600);
+  EXPECT_EQ(transport.ping_pong_recyle_time_, 600u);
+}
+
+// --- Provider management ---
+
+TEST(PacketTransportTest, AddProvider) {
+  TestablePacketTransport transport;
+  transport.add_provider("host1");
+  EXPECT_TRUE(transport.providers_.contains("host1"));
+  EXPECT_EQ(transport.providers_.size(), 1u);
+}
+
+TEST(PacketTransportTest, AddProviderDuplicate) {
+  TestablePacketTransport transport;
+  transport.add_provider("host1");
+  transport.add_provider("host1");
+  EXPECT_EQ(transport.providers_.size(), 1u);
+}
+
+TEST(PacketTransportTest, SetProviderEncryption) {
+  TestablePacketTransport transport;
+  transport.add_provider("host1");
+  std::vector<uint8_t> key(32, 0xCD);
+  transport.set_provider_encryption("host1", key);
+  EXPECT_EQ(transport.providers_["host1"].encryption_key, key);
+}
+
+// --- Sensor management (requires USE_SENSOR / USE_BINARY_SENSOR) ---
+
+#ifdef USE_SENSOR
+TEST(PacketTransportTest, AddSensor) {
+  TestablePacketTransport transport;
+  sensor::Sensor s;
+  transport.add_sensor("temp", &s);
+  ASSERT_EQ(transport.sensors_.size(), 1u);
+  EXPECT_STREQ(transport.sensors_[0].id, "temp");
+  EXPECT_EQ(transport.sensors_[0].sensor, &s);
+  EXPECT_TRUE(transport.sensors_[0].updated);
+}
+
+TEST(PacketTransportTest, AddRemoteSensor) {
+  TestablePacketTransport transport;
+  sensor::Sensor s;
+  transport.add_remote_sensor("host1", "remote_temp", &s);
+  EXPECT_TRUE(transport.providers_.contains("host1"));
+  EXPECT_EQ(transport.remote_sensors_["host1"]["remote_temp"], &s);
+}
+#endif
+
+#ifdef USE_BINARY_SENSOR
+TEST(PacketTransportTest, AddBinarySensor) {
+  TestablePacketTransport transport;
+  binary_sensor::BinarySensor bs;
+  transport.add_binary_sensor("motion", &bs);
+  ASSERT_EQ(transport.binary_sensors_.size(), 1u);
+  EXPECT_STREQ(transport.binary_sensors_[0].id, "motion");
+  EXPECT_EQ(transport.binary_sensors_[0].sensor, &bs);
+}
+
+TEST(PacketTransportTest, AddRemoteBinarySensor) {
+  TestablePacketTransport transport;
+  binary_sensor::BinarySensor bs;
+  transport.add_remote_binary_sensor("host1", "remote_motion", &bs);
+  EXPECT_TRUE(transport.providers_.contains("host1"));
+  EXPECT_EQ(transport.remote_binary_sensors_["host1"]["remote_motion"], &bs);
+}
+#endif
+
+// --- Unencrypted round-trip tests (require USE_SENSOR / USE_BINARY_SENSOR) ---
+
+#ifdef USE_SENSOR
+TEST(PacketTransportTest, UnencryptedSensorRoundTrip) {
+  // Encoder
+  TestablePacketTransport encoder;
+  encoder.init_for_test("sender");
+  sensor::Sensor local_sensor;
+  local_sensor.state = 42.5f;
+  encoder.add_sensor("temp", &local_sensor);
+
+  encoder.send_data_(true);
+  ASSERT_EQ(encoder.sent_packets.size(), 1u);
+
+  // Decoder
+  TestablePacketTransport decoder;
+  decoder.init_for_test("receiver");
+  sensor::Sensor remote_sensor;
+  remote_sensor.state = -999.0f;  // sentinel
+  decoder.add_remote_sensor("sender", "temp", &remote_sensor);
+
+  auto &packet = encoder.sent_packets[0];
+  decoder.process_({packet.data(), packet.size()});
+  EXPECT_FLOAT_EQ(remote_sensor.state, 42.5f);
+}
+#endif
+
+#ifdef USE_BINARY_SENSOR
+TEST(PacketTransportTest, UnencryptedBinarySensorRoundTrip) {
+  TestablePacketTransport encoder;
+  encoder.init_for_test("sender");
+  binary_sensor::BinarySensor local_bs;
+  local_bs.state = true;
+  encoder.add_binary_sensor("motion", &local_bs);
+
+  encoder.send_data_(true);
+  ASSERT_EQ(encoder.sent_packets.size(), 1u);
+
+  TestablePacketTransport decoder;
+  decoder.init_for_test("receiver");
+  binary_sensor::BinarySensor remote_bs;
+  decoder.add_remote_binary_sensor("sender", "motion", &remote_bs);
+
+  auto &packet = encoder.sent_packets[0];
+  decoder.process_({packet.data(), packet.size()});
+  EXPECT_TRUE(remote_bs.state);
+}
+#endif
+
+#if defined(USE_SENSOR) && defined(USE_BINARY_SENSOR)
+TEST(PacketTransportTest, MultipleSensorsRoundTrip) {
+  TestablePacketTransport encoder;
+  encoder.init_for_test("sender");
+
+  sensor::Sensor s1, s2;
+  s1.state = 10.0f;
+  s2.state = 20.0f;
+  encoder.add_sensor("s1", &s1);
+  encoder.add_sensor("s2", &s2);
+
+  binary_sensor::BinarySensor bs1;
+  bs1.state = true;
+  encoder.add_binary_sensor("bs1", &bs1);
+
+  encoder.send_data_(true);
+  ASSERT_EQ(encoder.sent_packets.size(), 1u);
+
+  TestablePacketTransport decoder;
+  decoder.init_for_test("receiver");
+  sensor::Sensor rs1, rs2;
+  binary_sensor::BinarySensor rbs1;
+  rs1.state = -999.0f;
+  rs2.state = -999.0f;
+  decoder.add_remote_sensor("sender", "s1", &rs1);
+  decoder.add_remote_sensor("sender", "s2", &rs2);
+  decoder.add_remote_binary_sensor("sender", "bs1", &rbs1);
+
+  auto &packet = encoder.sent_packets[0];
+  decoder.process_({packet.data(), packet.size()});
+
+  EXPECT_FLOAT_EQ(rs1.state, 10.0f);
+  EXPECT_FLOAT_EQ(rs2.state, 20.0f);
+  EXPECT_TRUE(rbs1.state);
+}
+#endif
+
+// --- Encrypted round-trip ---
+
+#ifdef USE_SENSOR
+TEST(PacketTransportTest, EncryptedSensorRoundTrip) {
+  std::vector<uint8_t> key(32);
+  for (int i = 0; i < 32; i++)
+    key[i] = i;
+
+  TestablePacketTransport encoder;
+  encoder.init_for_test("sender");
+  encoder.set_encryption_key(key);
+  sensor::Sensor local_sensor;
+  local_sensor.state = 99.9f;
+  encoder.add_sensor("temp", &local_sensor);
+
+  encoder.send_data_(true);
+  ASSERT_EQ(encoder.sent_packets.size(), 1u);
+
+  TestablePacketTransport decoder;
+  decoder.init_for_test("receiver");
+  sensor::Sensor remote_sensor;
+  remote_sensor.state = -999.0f;
+  decoder.add_remote_sensor("sender", "temp", &remote_sensor);
+  decoder.set_provider_encryption("sender", key);
+
+  auto &packet = encoder.sent_packets[0];
+  decoder.process_({packet.data(), packet.size()});
+  EXPECT_FLOAT_EQ(remote_sensor.state, 99.9f);
+}
+
+// --- Selective send ---
+
+TEST(PacketTransportTest, SendDataOnlyUpdated) {
+  TestablePacketTransport encoder;
+  encoder.init_for_test("sender");
+
+  sensor::Sensor s1, s2;
+  s1.state = 1.0f;
+  s2.state = 2.0f;
+  encoder.add_sensor("s1", &s1);
+  encoder.add_sensor("s2", &s2);
+
+  // Mark s1 as not updated, only s2 as updated
+  encoder.sensors_[0].updated = false;
+  encoder.sensors_[1].updated = true;
+
+  encoder.send_data_(false);
+  ASSERT_EQ(encoder.sent_packets.size(), 1u);
+
+  TestablePacketTransport decoder;
+  decoder.init_for_test("receiver");
+  sensor::Sensor rs1, rs2;
+  rs1.state = -999.0f;
+  rs2.state = -999.0f;
+  decoder.add_remote_sensor("sender", "s1", &rs1);
+  decoder.add_remote_sensor("sender", "s2", &rs2);
+
+  auto &packet = encoder.sent_packets[0];
+  decoder.process_({packet.data(), packet.size()});
+
+  EXPECT_FLOAT_EQ(rs1.state, -999.0f);  // not updated, not sent
+  EXPECT_FLOAT_EQ(rs2.state, 2.0f);     // updated, sent
+}
+#endif
+
+// --- Ping key tests ---
+
+TEST(PacketTransportTest, PingKeyStoredWhenEncrypted) {
+  TestablePacketTransport transport;
+  transport.init_for_test("receiver");
+  transport.set_encryption_key(std::vector<uint8_t>(32, 0xAA));
+
+  auto ping = build_ping_packet("requester", 0xDEADBEEF);
+  transport.process_({ping.data(), ping.size()});
+
+  ASSERT_EQ(transport.ping_keys_.size(), 1u);
+  EXPECT_EQ(transport.ping_keys_["requester"], 0xDEADBEEFu);
+}
+
+TEST(PacketTransportTest, PingKeyIgnoredWhenNotEncrypted) {
+  TestablePacketTransport transport;
+  transport.init_for_test("receiver");
+  // No encryption key — add_key_ should be a no-op
+
+  auto ping = build_ping_packet("requester", 0xDEADBEEF);
+  transport.process_({ping.data(), ping.size()});
+
+  EXPECT_TRUE(transport.ping_keys_.empty());
+}
+
+TEST(PacketTransportTest, PingKeyUpdatedOnRepeat) {
+  TestablePacketTransport transport;
+  transport.init_for_test("receiver");
+  transport.set_encryption_key(std::vector<uint8_t>(32, 0xAA));
+
+  auto ping1 = build_ping_packet("host1", 0x1111);
+  transport.process_({ping1.data(), ping1.size()});
+  EXPECT_EQ(transport.ping_keys_["host1"], 0x1111u);
+
+  // Same host, new key value — should update in place
+  auto ping2 = build_ping_packet("host1", 0x2222);
+  transport.process_({ping2.data(), ping2.size()});
+  EXPECT_EQ(transport.ping_keys_.size(), 1u);
+  EXPECT_EQ(transport.ping_keys_["host1"], 0x2222u);
+}
+
+TEST(PacketTransportTest, PingKeyMaxLimit) {
+  TestablePacketTransport transport;
+  transport.init_for_test("receiver");
+  transport.set_encryption_key(std::vector<uint8_t>(32, 0xAA));
+
+  // Fill to MAX_PING_KEYS (4)
+  for (int i = 0; i < 4; i++) {
+    char name[16];
+    snprintf(name, sizeof(name), "host%d", i);
+    auto ping = build_ping_packet(name, 0x1000 + i);
+    transport.process_({ping.data(), ping.size()});
+  }
+  EXPECT_EQ(transport.ping_keys_.size(), 4u);
+
+  // 5th key should be discarded
+  auto ping = build_ping_packet("host4", 0x9999);
+  transport.process_({ping.data(), ping.size()});
+  EXPECT_EQ(transport.ping_keys_.size(), 4u);
+  EXPECT_FALSE(transport.ping_keys_.contains("host4"));
+}
+
+#ifdef USE_SENSOR
+TEST(PacketTransportTest, PingKeyIncludedInTransmittedPacket) {
+  std::vector<uint8_t> key(32, 0xBB);
+
+  // Responder: encrypted, owns a sensor
+  TestablePacketTransport responder;
+  responder.init_for_test("responder");
+  responder.set_encryption_key(key);
+  sensor::Sensor local_sensor;
+  local_sensor.state = 77.7f;
+  responder.add_sensor("temp", &local_sensor);
+
+  // Requester sends a MAGIC_PING that the responder processes
+  auto ping = build_ping_packet("requester", 0xDEADBEEF);
+  responder.process_({ping.data(), ping.size()});
+  ASSERT_EQ(responder.ping_keys_.size(), 1u);
+
+  // Responder sends sensor data — ping key should be embedded
+  responder.send_data_(true);
+  ASSERT_EQ(responder.sent_packets.size(), 1u);
+
+  // Requester: encrypted provider, ping-pong enabled, expects key 0xDEADBEEF
+  TestablePacketTransport requester;
+  requester.init_for_test("requester");
+  requester.set_ping_pong_enable(true);
+  requester.ping_key_ = 0xDEADBEEF;
+  sensor::Sensor remote_sensor;
+  remote_sensor.state = -999.0f;
+  requester.add_remote_sensor("responder", "temp", &remote_sensor);
+  requester.set_provider_encryption("responder", key);
+
+  // The requester decrypts the packet and finds its ping key echoed back,
+  // which gates the sensor data — if the key is missing, data is blocked.
+  auto &packet = responder.sent_packets[0];
+  requester.process_({packet.data(), packet.size()});
+  EXPECT_FLOAT_EQ(remote_sensor.state, 77.7f);
+}
+
+TEST(PacketTransportTest, MissingPingKeyBlocksSensorData) {
+  std::vector<uint8_t> key(32, 0xBB);
+
+  // Responder sends data WITHOUT receiving any MAGIC_PING first — no ping keys
+  TestablePacketTransport responder;
+  responder.init_for_test("responder");
+  responder.set_encryption_key(key);
+  sensor::Sensor local_sensor;
+  local_sensor.state = 77.7f;
+  responder.add_sensor("temp", &local_sensor);
+  responder.send_data_(true);
+  ASSERT_EQ(responder.sent_packets.size(), 1u);
+
+  // Requester with ping-pong enabled expects a key that isn't in the packet
+  TestablePacketTransport requester;
+  requester.init_for_test("requester");
+  requester.set_ping_pong_enable(true);
+  requester.ping_key_ = 0xDEADBEEF;
+  sensor::Sensor remote_sensor;
+  remote_sensor.state = -999.0f;
+  requester.add_remote_sensor("responder", "temp", &remote_sensor);
+  requester.set_provider_encryption("responder", key);
+
+  auto &packet = responder.sent_packets[0];
+  requester.process_({packet.data(), packet.size()});
+  EXPECT_FLOAT_EQ(remote_sensor.state, -999.0f);  // blocked — ping key not found
+}
+#endif
+
+// --- Process error handling ---
+
+TEST(PacketTransportTest, ProcessShortBuffer) {
+  TestablePacketTransport transport;
+  transport.init_for_test("receiver");
+  uint8_t buf[] = {0x53};
+  // Too short for a magic number - should return safely
+  transport.process_({buf, 1});
+}
+
+TEST(PacketTransportTest, ProcessBadMagic) {
+  TestablePacketTransport transport;
+  transport.init_for_test("receiver");
+  uint8_t buf[] = {0xFF, 0xFF, 0x00, 0x00};
+  // Wrong magic - should return safely
+  transport.process_({buf, sizeof(buf)});
+}
+
+TEST(PacketTransportTest, ProcessOwnHostname) {
+  TestablePacketTransport transport;
+  transport.init_for_test("myself");
+  // Build a packet from "myself" using a separate encoder
+  TestablePacketTransport fake_sender;
+  fake_sender.init_for_test("myself");
+  fake_sender.send_data_(true);
+  ASSERT_EQ(fake_sender.sent_packets.size(), 1u);
+
+  auto &packet = fake_sender.sent_packets[0];
+  // Should be silently ignored because hostname matches our own
+  transport.process_({packet.data(), packet.size()});
+}
+
+TEST(PacketTransportTest, ProcessUnknownHostname) {
+  TestablePacketTransport transport;
+  transport.init_for_test("receiver");
+  // No providers registered - "unknown" will not be found
+  TestablePacketTransport sender;
+  sender.init_for_test("unknown");
+  sender.send_data_(true);
+  ASSERT_EQ(sender.sent_packets.size(), 1u);
+
+  auto &packet = sender.sent_packets[0];
+  // Should return safely without crash
+  transport.process_({packet.data(), packet.size()});
+}
+
+// --- Send disabled ---
+
+TEST(PacketTransportTest, NoSendWhenDisabled) {
+  TestablePacketTransport transport;
+  transport.init_for_test("sender");
+  transport.send_enabled = false;
+  transport.send_data_(true);
+  EXPECT_TRUE(transport.sent_packets.empty());
+}
+
+}  // namespace esphome::packet_transport::testing