Auto merge of #14407 - szeged:annotations, r=jdm

Annotations for WebBluetooth functions

<!-- Please describe your changes on the following line: -->
1. Moved the `convert_request_device_options` function steps into `request_bluetooth_devices` function, to stay consistent with the current specification.
2. Updated the existing step annotations for the requestDevice and related methods.
3. Added step annotations for the implemented WebBluetooth methods.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix  #14324, #12614

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

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components/bluetooth/lib.rs

@@ -567,6 +567,7 @@ impl BluetoothManager {
     fn request_device(&mut self,
                       options: RequestDeviceoptions,
                       sender: IpcSender<BluetoothResponseResult>) {
+        // Step 6.
         let mut adapter = get_adapter_or_return_error!(self, sender);
         if let Ok(ref session) = adapter.create_discovery_session() {
             if session.start_discovery().is_ok() {
@@ -577,18 +578,20 @@ impl BluetoothManager {
             let _ = session.stop_discovery();
         }
 
-        // Step 6.
+        // Step 7.
-        // Note: There is no requiredServiceUUIDS, we scan for all devices.
+        // Note: There are no requiredServiceUUIDS, we scan for all devices.
         let mut matched_devices = self.get_and_cache_devices(&mut adapter);
 
-        // Step 7.
+        // Step 8.
         if !options.is_accepting_all_devices() {
             matched_devices = matched_devices.into_iter()
                                              .filter(|d| matches_filters(d, options.get_filters()))
                                              .collect();
         }
 
-        // Step 8.
+        // Step 9.
+        // TODO: After the permission API implementation
+        //       https://w3c.github.io/permissions/#prompt-the-user-to-choose
         if let Some(address) = self.select_device(matched_devices, &adapter) {
             let device_id = match self.address_to_id.get(&address) {
                 Some(id) => id.clone(),
@@ -610,11 +613,16 @@ impl BluetoothManager {
                 return drop(sender.send(Ok(BluetoothResponse::RequestDevice(message))));
             }
         }
+        // TODO: Step 10 - 11: Implement the permission API.
         return drop(sender.send(Err(BluetoothError::NotFound)));
+        // Step 12: Missing, because it is optional.
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-connect
     fn gatt_server_connect(&mut self, device_id: String, sender: IpcSender<BluetoothResponseResult>) {
         let mut adapter = get_adapter_or_return_error!(self, sender);
+
+        // Step 5.1.1.
         match self.get_device(&mut adapter, &device_id) {
             Some(d) => {
                 if d.is_connected().unwrap_or(false) {
@@ -631,18 +639,22 @@ impl BluetoothManager {
                             thread::sleep(Duration::from_millis(CONNECTION_TIMEOUT_MS));
                         },
                     }
+                // TODO: Step 5.1.4: Use the exchange MTU procedure.
                 }
+                // Step 5.1.3.
                 return drop(sender.send(Err(BluetoothError::Network)));
             },
             None => return drop(sender.send(Err(BluetoothError::NotFound))),
         }
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-disconnect
     fn gatt_server_disconnect(&mut self, device_id: String, sender: IpcSender<BluetoothResult<bool>>) {
         let mut adapter = get_adapter_or_return_error!(self, sender);
 
         match self.get_device(&mut adapter, &device_id) {
             Some(d) => {
+                // Step 2.
                 if !d.is_connected().unwrap_or(true) {
                     return drop(sender.send(Ok(false)));
                 }
@@ -659,10 +671,13 @@ impl BluetoothManager {
         }
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-getprimaryservice
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_primary_service(&mut self,
                            device_id: String,
                            uuid: String,
                            sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_devices.contains_key(&device_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
@@ -671,9 +686,8 @@ impl BluetoothManager {
             return drop(sender.send(Err(BluetoothError::Security)));
         }
         let services = self.get_gatt_services_by_uuid(&mut adapter, &device_id, &uuid);
-        if services.is_empty() {
+
-            return drop(sender.send(Err(BluetoothError::NotFound)));
+        // Step 6.
-        }
         for service in services {
             if service.is_primary().unwrap_or(false) {
                 if let Ok(uuid) = service.get_uuid() {
@@ -689,13 +703,17 @@ impl BluetoothManager {
                 }
             }
         }
+        // Step 7.
         return drop(sender.send(Err(BluetoothError::NotFound)));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-getprimaryservices
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_primary_services(&mut self,
                             device_id: String,
                             uuid: Option<String>,
                             sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_devices.contains_key(&device_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
@@ -709,9 +727,8 @@ impl BluetoothManager {
             },
             None => self.get_and_cache_gatt_services(&mut adapter, &device_id),
         };
-        if services.is_empty() {
+
-            return drop(sender.send(Err(BluetoothError::NotFound)));
+        // Step 6.
-        }
         let mut services_vec = vec!();
         for service in services {
             if service.is_primary().unwrap_or(false) {
@@ -730,6 +747,8 @@ impl BluetoothManager {
                                 self.allowed_services
                                     .get(&device_id)
                                     .map_or(false, |uuids| uuids.contains(&s.uuid)));
+
+        // Step 7.
         if services_vec.is_empty() {
             return drop(sender.send(Err(BluetoothError::NotFound)));
         }
@@ -737,10 +756,13 @@ impl BluetoothManager {
         return drop(sender.send(Ok(BluetoothResponse::GetPrimaryServices(services_vec))));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getincludedservice
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_included_service(&mut self,
                             service_id: String,
                             uuid: String,
                             sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_services.contains_key(&service_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
@@ -754,6 +776,8 @@ impl BluetoothManager {
             None => return drop(sender.send(Err(BluetoothError::NotFound))),
         };
         let services = primary_service.get_includes(device).unwrap_or(vec!());
+
+        // Step 6.
         for service in services {
             if let Ok(service_uuid) = service.get_uuid() {
                 if uuid == service_uuid {
@@ -769,13 +793,17 @@ impl BluetoothManager {
                 }
             }
         }
+        // Step 7.
         return drop(sender.send(Err(BluetoothError::NotFound)));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getincludedservices
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_included_services(&mut self,
                              service_id: String,
                              uuid: Option<String>,
                              sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_services.contains_key(&service_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
@@ -789,6 +817,8 @@ impl BluetoothManager {
             None => return drop(sender.send(Err(BluetoothError::NotFound))),
         };
         let services = primary_service.get_includes(device).unwrap_or(vec!());
+
+        // Step 6.
         let mut services_vec = vec!();
         for service in services {
             if let Ok(service_uuid) = service.get_uuid() {
@@ -805,6 +835,8 @@ impl BluetoothManager {
             services_vec.retain(|ref s| s.uuid == uuid);
         }
         services_vec.retain(|s| !uuid_is_blocklisted(&s.uuid, Blocklist::All));
+
+        // Step 7.
         if services_vec.is_empty() {
             return drop(sender.send(Err(BluetoothError::NotFound)));
         }
@@ -812,18 +844,20 @@ impl BluetoothManager {
         return drop(sender.send(Ok(BluetoothResponse::GetIncludedServices(services_vec))));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getcharacteristic
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_characteristic(&mut self,
                           service_id: String,
                           uuid: String,
                           sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_services.contains_key(&service_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
         let mut adapter = get_adapter_or_return_error!(self, sender);
         let characteristics = self.get_gatt_characteristics_by_uuid(&mut adapter, &service_id, &uuid);
-        if characteristics.is_empty() {
+
-            return drop(sender.send(Err(BluetoothError::NotFound)));
+        // Step 6.
-        }
         for characteristic in characteristics {
             if let Ok(uuid) = characteristic.get_uuid() {
                 let properties = self.get_characteristic_properties(&characteristic);
@@ -843,13 +877,17 @@ impl BluetoothManager {
                 return drop(sender.send(Ok(BluetoothResponse::GetCharacteristic(message))));
             }
         }
+        // Step 7.
         return drop(sender.send(Err(BluetoothError::NotFound)));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getcharacteristics
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_characteristics(&mut self,
                            service_id: String,
                            uuid: Option<String>,
                            sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_services.contains_key(&service_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
@@ -858,9 +896,8 @@ impl BluetoothManager {
             Some(id) => self.get_gatt_characteristics_by_uuid(&mut adapter, &service_id, &id),
             None => self.get_and_cache_gatt_characteristics(&mut adapter, &service_id),
         };
-        if characteristics.is_empty() {
+
-            return drop(sender.send(Err(BluetoothError::NotFound)));
+        // Step 6.
-        }
         let mut characteristics_vec = vec!();
         for characteristic in characteristics {
             if let Ok(uuid) = characteristic.get_uuid() {
@@ -883,6 +920,8 @@ impl BluetoothManager {
             }
         }
         characteristics_vec.retain(|c| !uuid_is_blocklisted(&c.uuid, Blocklist::All));
+
+        // Step 7.
         if characteristics_vec.is_empty() {
             return drop(sender.send(Err(BluetoothError::NotFound)));
         }
@@ -890,18 +929,20 @@ impl BluetoothManager {
         return drop(sender.send(Ok(BluetoothResponse::GetCharacteristics(characteristics_vec))));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-getdescriptor
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_descriptor(&mut self,
                       characteristic_id: String,
                       uuid: String,
                       sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_characteristics.contains_key(&characteristic_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
         let mut adapter = get_adapter_or_return_error!(self, sender);
         let descriptors = self.get_gatt_descriptors_by_uuid(&mut adapter, &characteristic_id, &uuid);
-        if descriptors.is_empty() {
+
-            return drop(sender.send(Err(BluetoothError::NotFound)));
+        // Step 6.
-        }
         for descriptor in descriptors {
             if let Ok(uuid) = descriptor.get_uuid() {
                 return drop(sender.send(
@@ -914,13 +955,17 @@ impl BluetoothManager {
                 ));
             }
         }
+        // Step 7.
         return drop(sender.send(Err(BluetoothError::NotFound)));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-getdescriptors
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn get_descriptors(&mut self,
                        characteristic_id: String,
                        uuid: Option<String>,
                        sender: IpcSender<BluetoothResponseResult>) {
+        // Step 5.
         if !self.cached_characteristics.contains_key(&characteristic_id) {
             return drop(sender.send(Err(BluetoothError::InvalidState)));
         }
@@ -929,9 +974,8 @@ impl BluetoothManager {
             Some(id) => self.get_gatt_descriptors_by_uuid(&mut adapter, &characteristic_id, &id),
             None => self.get_and_cache_gatt_descriptors(&mut adapter, &characteristic_id),
         };
-        if descriptors.is_empty() {
+
-            return drop(sender.send(Err(BluetoothError::NotFound)));
+        // Step 6.
-        }
         let mut descriptors_vec = vec!();
         for descriptor in descriptors {
             if let Ok(uuid) = descriptor.get_uuid() {
@@ -944,60 +988,108 @@ impl BluetoothManager {
             }
         }
         descriptors_vec.retain(|d| !uuid_is_blocklisted(&d.uuid, Blocklist::All));
+
+        // Step 7.
         if descriptors_vec.is_empty() {
             return drop(sender.send(Err(BluetoothError::NotFound)));
         }
         return drop(sender.send(Ok(BluetoothResponse::GetDescriptors(descriptors_vec))));
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-readvalue
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-readvalue
     fn read_value(&mut self, id: String, sender: IpcSender<BluetoothResponseResult>) {
+        // (Characteristic) Step 5.2: Missing because it is optional.
+        // (Descriptor)     Step 5.1: Missing because it is optional.
         let mut adapter = get_adapter_or_return_error!(self, sender);
+
+        // (Characteristic) Step 5.3.
         let mut value = self.get_gatt_characteristic(&mut adapter, &id)
                             .map(|c| c.read_value().unwrap_or(vec![]));
+
+        // (Characteristic) TODO: Step 5.4: Handle all the errors returned from the read_value call.
+
+        // (Descriptor) Step 5.2.
         if value.is_none() {
             value = self.get_gatt_descriptor(&mut adapter, &id)
                         .map(|d| d.read_value().unwrap_or(vec![]));
         }
+
+        // (Descriptor) TODO: Step 5.3: Handle all the errors returned from the read_value call.
+
         match value {
+            // (Characteristic) Step 5.5.4.
+            // (Descriptor)     Step 5.4.3.
             Some(v) => return drop(sender.send(Ok(BluetoothResponse::ReadValue(v)))),
+
+            // (Characteristic) Step 4.
+            // (Descriptor)     Step 4.
             None => return drop(sender.send(Err(BluetoothError::InvalidState))),
         }
     }
 
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-writevalue
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-writevalue
     fn write_value(&mut self, id: String, value: Vec<u8>, sender: IpcSender<BluetoothResponseResult>) {
+        // (Characteristic) Step 7.2: Missing because it is optional.
+        // (Descriptor)     Step 7.1: Missing because it is optional.
         let mut adapter = get_adapter_or_return_error!(self, sender);
+
+        // (Characteristic) Step 7.3.
         let mut result = self.get_gatt_characteristic(&mut adapter, &id)
                              .map(|c| c.write_value(value.clone()));
+
+        // (Characteristic) TODO: Step 7.4: Handle all the errors returned from the write_value call.
+
+        // (Descriptor) Step 7.2.
         if result.is_none() {
             result = self.get_gatt_descriptor(&mut adapter, &id)
                          .map(|d| d.write_value(value.clone()));
         }
+
+        // (Descriptor) TODO: Step 7.3: Handle all the errors returned from the write_value call.
+
         match result {
             Some(v) => match v {
+                // (Characteristic) Step 7.5.3.
+                // (Descriptor) Step 7.4.3.
                 Ok(_) => return drop(sender.send(Ok(BluetoothResponse::WriteValue(value)))),
+
+                // (Characteristic) Step 7.1.
                 Err(_) => return drop(sender.send(Err(BluetoothError::NotSupported))),
             },
+
+            // (Characteristic) Step 6.
+            // (Descriptor)     Step 6.
             None => return drop(sender.send(Err(BluetoothError::InvalidState))),
         }
     }
 
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-startnotifications
+    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-stopnotifications
     fn enable_notification(&mut self, id: String, enable: bool, sender: IpcSender<BluetoothResponseResult>) {
+        // (StartNotification) TODO: Step 7: Missing because it is optional.
         let mut adapter = get_adapter_or_return_error!(self, sender);
         match self.get_gatt_characteristic(&mut adapter, &id) {
             Some(c) => {
                 let result = match enable {
+                    // (StartNotification) Step 8.
+                    // TODO: Handle all the errors returned from the start_notify call.
                     true => c.start_notify(),
+
+                    // (StopNotification) Step 4.
                     false => c.stop_notify(),
                 };
                 match result {
-                    // Step 11.
+                    // (StartNotification) Step 11.
+                    // (StopNotification)  Step 5.
                     Ok(_) => return drop(sender.send(Ok(BluetoothResponse::EnableNotification(())))),
-                    // Step 4.
+
+                    // (StartNotification) Step 4.
                     Err(_) => return drop(sender.send(Err(BluetoothError::NotSupported))),
                 }
             },
-            // Step 3.
+            // (StartNotification) Step 3.
             None => return drop(sender.send(Err(BluetoothError::InvalidState))),
         }
     }

components/script/dom/bluetooth.rs

@@ -78,6 +78,8 @@ impl<Listener: AsyncBluetoothListener + Reflectable> BluetoothResponseListener f
         let _ac = JSAutoCompartment::new(promise_cx, promise.reflector().get_jsobject().get());
         match response {
             Ok(response) => self.receiver.root().handle_response(response, promise_cx, &promise),
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetooth-requestdevice
+            // Step 3 - 4.
             Err(error) => promise.reject_error(promise_cx, Error::from(error)),
         }
     }
@@ -134,15 +136,57 @@ impl Bluetooth {
                                  optional_services: &Option<Vec<BluetoothServiceUUID>>) {
         // TODO: Step 1: Triggered by user activation.
 
-        // Step 2.
+        // Step 2.2: There are no requiredServiceUUIDS, we scan for all devices.
-        let option = match convert_request_device_options(filters, optional_services) {
+        let mut uuid_filters = vec!();
-            Ok(o) => o,
+
+        if let &Some(ref filters) = filters {
+            // Step 2.1.
+            if filters.is_empty()  {
+                p.reject_error(p.global().get_cx(), Type(FILTER_EMPTY_ERROR.to_owned()));
+                return;
+            }
+
+            // Step 2.3: There are no requiredServiceUUIDS, we scan for all devices.
+
+            // Step 2.4.
+            for filter in filters {
+                // Step 2.4.1.
+                match canonicalize_filter(&filter) {
+                    // Step 2.4.2.
+                    Ok(f) => uuid_filters.push(f),
                     Err(e) => {
                         p.reject_error(p.global().get_cx(), e);
                         return;
+                    },
                 }
+                // Step 2.4.3: There are no requiredServiceUUIDS, we scan for all devices.
+            }
+        }
+
+        let mut optional_services_uuids = vec!();
+        if let &Some(ref opt_services) = optional_services {
+            for opt_service in opt_services {
+                // Step 2.5 - 2.6.
+                let uuid = match BluetoothUUID::service(opt_service.clone()) {
+                    Ok(u) => u.to_string(),
+                    Err(e) => {
+                        p.reject_error(p.global().get_cx(), e);
+                        return;
+                    },
                 };
 
+                // Step 2.7.
+                // Note: What we are doing here, is adding the not blocklisted UUIDs to the result vector,
+                // instead of removing them from an already filled vector.
+                if !uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
+                    optional_services_uuids.push(uuid);
+                }
+            }
+        }
+
+        let option = RequestDeviceoptions::new(BluetoothScanfilterSequence::new(uuid_filters),
+                                               ServiceUUIDSequence::new(optional_services_uuids));
+
         // TODO: Step 3 - 5: Implement the permission API.
 
         // Note: Steps 6 - 8 are implemented in
@@ -172,50 +216,9 @@ pub fn response_async<T: AsyncBluetoothListener + Reflectable + 'static>(
     action_sender
 }
 
-// https://webbluetoothcg.github.io/web-bluetooth/#request-bluetooth-devices
+// https://webbluetoothcg.github.io/web-bluetooth/#bluetoothlescanfilterinit-canonicalizing
-fn convert_request_device_options(filters: &Option<Vec<BluetoothLEScanFilterInit>>,
-                                  optional_services: &Option<Vec<BluetoothServiceUUID>>)
-                                  -> Fallible<RequestDeviceoptions> {
-    // Step 2.2: There is no requiredServiceUUIDS, we scan for all devices.
-    let mut uuid_filters = vec!();
-
-    if let &Some(ref filters) = filters {
-        // Step 2.1.
-        if filters.is_empty()  {
-            return Err(Type(FILTER_EMPTY_ERROR.to_owned()));
-        }
-
-        // Step 2.3: There is no requiredServiceUUIDS, we scan for all devices.
-
-        // Step 2.4.
-        for filter in filters {
-            // Step 2.4.8.
-            uuid_filters.push(try!(canonicalize_filter(&filter)));
-        }
-    }
-
-    let mut optional_services_uuids = vec!();
-    if let &Some(ref opt_services) = optional_services {
-        for opt_service in opt_services {
-            // Step 2.5 - 2.6.
-            let uuid = try!(BluetoothUUID::service(opt_service.clone())).to_string();
-
-            // Step 2.7.
-            // Note: What we are doing here is adding the not blocklisted UUIDs to the result vector,
-            // insted of removing them from an already filled vector.
-            if !uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
-                optional_services_uuids.push(uuid);
-            }
-        }
-    }
-
-    Ok(RequestDeviceoptions::new(BluetoothScanfilterSequence::new(uuid_filters),
-                                 ServiceUUIDSequence::new(optional_services_uuids)))
-}
-
-// https://webbluetoothcg.github.io/web-bluetooth/#request-bluetooth-devices
 fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<BluetoothScanfilter> {
-    // Step 2.4.1.
+    // Step 1.
     if filter.services.is_none() &&
        filter.name.is_none() &&
        filter.namePrefix.is_none() &&
@@ -224,13 +227,13 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
            return Err(Type(FILTER_ERROR.to_owned()));
     }
 
-    // Step 2.4.2: There is no empty canonicalizedFilter member,
+    // Step 2: There is no empty canonicalizedFilter member,
     // we create a BluetoothScanfilter instance at the end of the function.
 
-    // Step 2.4.3.
+    // Step 3.
     let services_vec = match filter.services {
         Some(ref services) => {
-            // Step 2.4.3.1.
+            // Step 3.1.
             if services.is_empty() {
                 return Err(Type(SERVICE_ERROR.to_owned()));
             }
@@ -238,27 +241,26 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
             let mut services_vec = vec!();
 
             for service in services {
-                // Step 2.4.3.2 - 2.4.3.3.
+                // Step 3.2 - 3.3.
                 let uuid = try!(BluetoothUUID::service(service.clone())).to_string();
 
-                // Step 2.4.3.4.
+                // Step 3.4.
                 if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
                     return Err(Security)
                 }
 
                 services_vec.push(uuid);
             }
-            // Step 2.4.3.5.
+            // Step 3.5.
             services_vec
-            // Step 2.4.3.6: There is no requiredServiceUUIDS, we scan for all devices.
         },
         None => vec!(),
     };
 
-    // Step 2.4.4.
+    // Step 4.
     let name = match filter.name {
         Some(ref name) => {
-            // Step 2.4.4.1.
+            // Step 4.1.
             // Note: DOMString::len() gives back the size in bytes.
             if name.len() > MAX_DEVICE_NAME_LENGTH {
                 return Err(Type(NAME_TOO_LONG_ERROR.to_owned()));
@@ -267,16 +269,16 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
                 return Err(NotFound);
             }
 
-            // Step 2.4.4.2.
+            // Step 4.2.
             Some(name.to_string())
         },
         None => None,
     };
 
-    // Step 2.4.5.
+    // Step 5.
     let name_prefix = match filter.namePrefix {
         Some(ref name_prefix) => {
-            // Step 2.4.5.1.
+            // Step 5.1.
             if name_prefix.is_empty() {
                 return Err(Type(NAME_PREFIX_ERROR.to_owned()));
             }
@@ -287,24 +289,30 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
                 return Err(NotFound);
             }
 
-            // Step 2.4.5.2.
+            // Step 5.2.
             name_prefix.to_string()
         },
         None => String::new(),
     };
 
-    // Step 2.4.6 - 2.4.7
+    // Step 6 - 7.
     let manufacturer_data = match filter.manufacturerData {
         Some(ref manufacturer_data_map) => {
+            // Note: If manufacturer_data_map is empty, that means there are no key values in it.
             if manufacturer_data_map.is_empty() {
                 return Err(Type(MANUFACTURER_DATA_ERROR.to_owned()));
             }
             let mut map = HashMap::new();
             for (key, bdfi) in manufacturer_data_map.iter() {
+                // Step 7.1 - 7.2.
                 let manufacturer_id = match u16::from_str(key.as_ref()) {
                     Ok(id) => id,
                     Err(err) => return Err(Type(format!("{} {} {}", KEY_CONVERSION_ERROR, key, err))),
                 };
+
+                // Step 7.3: No need to convert to IDL values since this is only used by native code.
+
+                // Step 7.4 - 7.5.
                 map.insert(manufacturer_id, try!(canonicalize_bluetooth_data_filter_init(bdfi)));
             }
             Some(map)
@@ -312,22 +320,33 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
         None => None,
     };
 
-    // Step 2.4.8 -2.4.9
+    // Step 8 - 9.
     let service_data = match filter.serviceData {
         Some(ref service_data_map) => {
+            // Note: If service_data_map is empty, that means there are no key values in it.
             if service_data_map.is_empty() {
                 return Err(Type(SERVICE_DATA_ERROR.to_owned()));
             }
             let mut map = HashMap::new();
             for (key, bdfi) in service_data_map.iter() {
                 let service_name = match u32::from_str(key.as_ref()) {
+                    // Step 9.1.
                     Ok(number) => StringOrUnsignedLong::UnsignedLong(number),
+                    // Step 9.2.
                     _ => StringOrUnsignedLong::String(key.clone())
                 };
+
+                // Step 9.3 - 9.4.
                 let service = try!(BluetoothUUID::service(service_name)).to_string();
+
+                // Step 9.5.
                 if uuid_is_blocklisted(service.as_ref(), Blocklist::All) {
                     return Err(Security);
                 }
+
+                // Step 9.6: No need to convert to IDL values since this is only used by native code.
+
+                // Step 9.7 - 9.8.
                 map.insert(service, try!(canonicalize_bluetooth_data_filter_init(bdfi)));
             }
             Some(map)
@@ -343,14 +362,17 @@ fn canonicalize_filter(filter: &BluetoothLEScanFilterInit) -> Fallible<Bluetooth
 fn canonicalize_bluetooth_data_filter_init(bdfi: &BluetoothDataFilterInit) -> Fallible<(Vec<u8>, Vec<u8>)> {
     // Step 1.
     let data_prefix = bdfi.dataPrefix.clone().unwrap_or(vec![]);
+
     // Step 2.
     // If no mask present, mask will be a sequence of 0xFF bytes the same length as dataPrefix.
     // Masking dataPrefix with this, leaves dataPrefix untouched.
     let mask = bdfi.mask.clone().unwrap_or(vec![0xFF; data_prefix.len()]);
+
     // Step 3.
     if mask.len() != data_prefix.len() {
         return Err(Type(MASK_LENGTH_ERROR.to_owned()));
     }
+
     // Step 4.
     Ok((data_prefix, mask))
 }
@@ -379,9 +401,10 @@ impl BluetoothMethods for Bluetooth {
             p.reject_error(p.global().get_cx(), Error::Type(OPTIONS_ERROR.to_owned()));
             return p;
         }
+
         // Step 2.
         self.request_bluetooth_devices(&p, &option.filters, &option.optionalServices);
-        // TODO(#4282): Step 3-5: Reject and resolve promise.
+        //Note: Step 3 - 4. in response function, Step 5. in handle_response function.
         return p;
     }
 
@@ -392,6 +415,8 @@ impl BluetoothMethods for Bluetooth {
 impl AsyncBluetoothListener for Bluetooth {
     fn handle_response(&self, response: BluetoothResponse, promise_cx: *mut JSContext, promise: &Rc<Promise>) {
         match response {
+            // https://webbluetoothcg.github.io/web-bluetooth/#request-bluetooth-devices
+            // Step 13 - 14.
             BluetoothResponse::RequestDevice(device) => {
                 let mut device_instance_map = self.device_instance_map.borrow_mut();
                 if let Some(existing_device) = device_instance_map.get(&device.id.clone()) {
@@ -407,6 +432,8 @@ impl AsyncBluetoothListener for Bluetooth {
                                                      &ad_data,
                                                      &self);
                 device_instance_map.insert(device.id, MutHeap::new(&bt_device));
+                // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetooth-requestdevice
+                // Step 5.
                 promise.resolve_native(promise_cx, &bt_device);
             },
             _ => promise.reject_error(promise_cx, Error::Type("Something went wrong...".to_owned())),

components/script/dom/bluetoothdevice.rs

@@ -78,6 +78,7 @@ impl BluetoothDeviceMethods for BluetoothDevice {
 
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-gatt
     fn Gatt(&self) -> Root<BluetoothRemoteGATTServer> {
+        // TODO: Step 1 - 2: Implement the Permission API.
         self.gatt.or_init(|| {
             BluetoothRemoteGATTServer::new(&self.global(), self)
         })

components/script/dom/bluetoothremotegattcharacteristic.rs

@@ -103,9 +103,12 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
 
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-getdescriptor
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn GetDescriptor(&self, descriptor: BluetoothDescriptorUUID) -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         let uuid = match BluetoothUUID::descriptor(descriptor) {
             Ok(uuid) => uuid.to_string(),
             Err(e) => {
@@ -113,14 +116,23 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
                 return p;
             }
         };
+
+        // Step 2.
         if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 3 - 4.
         if !self.Service().Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedService internal slot for BluetoothRemoteGATTService.
+
+        // Note: Steps 6 - 7 are implemented in components/bluetooth/lib.rs in get_descriptor function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetDescriptor(self.get_instance_id(), uuid, sender)).unwrap();
@@ -129,6 +141,7 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
 
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-getdescriptors
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn GetDescriptors(&self,
                       descriptor: Option<BluetoothDescriptorUUID>)
                       -> Rc<Promise> {
@@ -136,6 +149,7 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
         let p_cx = p.global().get_cx();
         let mut uuid: Option<String> = None;
         if let Some(d) = descriptor {
+            // Step 1.
             uuid = match BluetoothUUID::descriptor(d) {
                 Ok(uuid) => Some(uuid.to_string()),
                 Err(e) => {
@@ -144,16 +158,24 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
                 }
             };
             if let Some(ref uuid) = uuid {
+                // Step 2.
                 if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
                     p.reject_error(p_cx, Security);
                     return p;
                 }
             }
         };
+
+        // Step 3 - 4.
         if !self.Service().Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedService internal slot for BluetoothRemoteGATTService.
+
+        // Note: Steps 6 - 7 are implemented in components/bluetooth/lib.rs in get_descriptors function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetDescriptors(self.get_instance_id(), uuid, sender)).unwrap();
@@ -170,18 +192,31 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
     fn ReadValue(&self) -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         if uuid_is_blocklisted(self.uuid.as_ref(), Blocklist::Reads) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 2.
         if !self.Service().Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 3 - 4: Implement representedCharacteristic internal slot for BluetoothRemoteGATTCharacteristic.
+
+        // TODO: Step 5: Implement the `connection-checking-wrapper` algorithm for BluetoothRemoteGATTServer.
+
+        // Step 5.1.
         if !self.Properties().Read() {
             p.reject_error(p_cx, NotSupported);
             return p;
         }
+
+        // Note: Remaining substeps of Step 5 are implemented in components/bluetooth/lib.rs in readValue function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::ReadValue(self.get_instance_id(), sender)).unwrap();
@@ -193,25 +228,39 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
     fn WriteValue(&self, value: Vec<u8>) -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         if uuid_is_blocklisted(self.uuid.as_ref(), Blocklist::Writes) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 2 - 3.
         if value.len() > MAXIMUM_ATTRIBUTE_LENGTH {
             p.reject_error(p_cx, InvalidModification);
             return p;
         }
+
+        // Step 4.
         if !self.Service().Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
 
+        // TODO: Step 5 - 6: Implement representedCharacteristic internal slot for BluetoothRemoteGATTCharacteristic.
+
+        // TODO: Step 7: Implement the `connection-checking-wrapper` algorithm for BluetoothRemoteGATTServer.
+
+        // Step 7.1.
         if !(self.Properties().Write() ||
              self.Properties().WriteWithoutResponse() ||
              self.Properties().AuthenticatedSignedWrites()) {
             p.reject_error(p_cx, NotSupported);
             return p;
         }
+
+        // Note: Remaining substeps of Step 7 are implemented in components/bluetooth/lib.rs in writeValue function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::WriteValue(self.get_instance_id(), value, sender)).unwrap();
@@ -223,22 +272,32 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
     fn StartNotifications(&self) -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
         // Step 1.
         if uuid_is_blocklisted(self.uuid.as_ref(), Blocklist::Reads) {
             p.reject_error(p_cx, Security);
             return p;
         }
-        // Step 3.
+
+        // TODO: Step 2 - 3: Implement representedCharacteristic internal slot for BluetoothRemoteGATTCharacteristic.
+
+        // Step 4.
         if !(self.Properties().Notify() ||
              self.Properties().Indicate()) {
             p.reject_error(p_cx, NotSupported);
             return p;
         }
+
+        // TODO: Step 5: Implement `active notification context set` for BluetoothRemoteGATTCharacteristic.
+
         // Step 6.
         if !self.Service().Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // Note: Steps 7 - 11 are implemented in components/bluetooth/lib.rs in enable_notification function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::EnableNotification(self.get_instance_id(),
@@ -252,6 +311,12 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
     fn StopNotifications(&self) -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let sender = response_async(&p, self);
+
+        // TODO: Step 1 - 4: Implement representedCharacteristic internal slot and
+        // `active notification context set` for BluetoothRemoteGATTCharacteristic,
+
+        // Note: Part of Step 4 and Step 5 are implemented in components/bluetooth/lib.rs in enable_notification
+        // function and in handle_response function.
         self.get_bluetooth_thread().send(
             BluetoothRequest::EnableNotification(self.get_instance_id(),
                                                  false,
@@ -266,6 +331,9 @@ impl BluetoothRemoteGATTCharacteristicMethods for BluetoothRemoteGATTCharacteris
 impl AsyncBluetoothListener for BluetoothRemoteGATTCharacteristic {
     fn handle_response(&self, response: BluetoothResponse, promise_cx: *mut JSContext, promise: &Rc<Promise>) {
         match response {
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-getdescriptor
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetDescriptor(descriptor) => {
                 let context = self.service.get().get_device().get_context();
                 let mut descriptor_map = context.get_descriptor_map().borrow_mut();
@@ -279,6 +347,9 @@ impl AsyncBluetoothListener for BluetoothRemoteGATTCharacteristic {
                 descriptor_map.insert(descriptor.instance_id, MutHeap::new(&bt_descriptor));
                 promise.resolve_native(promise_cx, &bt_descriptor);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-getdescriptors
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetDescriptors(descriptors_vec) => {
                 let mut descriptors = vec!();
                 let context = self.service.get().get_device().get_context();
@@ -300,17 +371,40 @@ impl AsyncBluetoothListener for BluetoothRemoteGATTCharacteristic {
                 }
                 promise.resolve_native(promise_cx, &descriptors);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-readvalue
             BluetoothResponse::ReadValue(result) => {
+                // TODO: Step 5.5.1: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.
+
+                // Step 5.5.2.
+                // TODO(#5014): Replace ByteString with ArrayBuffer when it is implemented.
                 let value = ByteString::new(result);
                 *self.value.borrow_mut() = Some(value.clone());
+
+                // Step 5.5.3.
                 self.upcast::<EventTarget>().fire_bubbling_event(atom!("characteristicvaluechanged"));
+
+                // Step 5.5.4.
                 promise.resolve_native(promise_cx, &value);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-writevalue
             BluetoothResponse::WriteValue(result) => {
+                // TODO: Step 7.5.1: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.
+
+                // Step 7.5.2.
+                // TODO(#5014): Replace ByteString with an ArrayBuffer wrapped in a DataView.
                 *self.value.borrow_mut() = Some(ByteString::new(result));
+
+                // Step 7.5.3.
                 promise.resolve_native(promise_cx, &());
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-startnotifications
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattcharacteristic-stopnotifications
             BluetoothResponse::EnableNotification(_result) => {
+                // (StartNotification) TODO: Step 10:  Implement `active notification context set`
+                // for BluetoothRemoteGATTCharacteristic.
+
+                // (StartNotification) Step 11.
+                // (StopNotification)  Step 5.
                 promise.resolve_native(promise_cx, self);
             },
             _ => promise.reject_error(promise_cx, Error::Type("Something went wrong...".to_owned())),

components/script/dom/bluetoothremotegattdescriptor.rs

@@ -90,14 +90,24 @@ impl BluetoothRemoteGATTDescriptorMethods for BluetoothRemoteGATTDescriptor {
     fn ReadValue(&self) -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         if uuid_is_blocklisted(self.uuid.as_ref(), Blocklist::Reads) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 2.
         if !self.Characteristic().Service().Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 3 - 4: Implement representedDescriptor internal slot for BluetoothRemoteGATTDescriptor.
+
+        // TODO: Step 5: Implement the `connection-checking-wrapper` algorithm for BluetoothRemoteGATTServer.
+        // Note: Substeps of Step 5 are implemented in components/bluetooth/lib.rs in readValue function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::ReadValue(self.get_instance_id(), sender)).unwrap();
@@ -109,18 +119,30 @@ impl BluetoothRemoteGATTDescriptorMethods for BluetoothRemoteGATTDescriptor {
     fn WriteValue(&self, value: Vec<u8>) -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         if uuid_is_blocklisted(self.uuid.as_ref(), Blocklist::Writes) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 2 - 3.
         if value.len() > MAXIMUM_ATTRIBUTE_LENGTH {
             p.reject_error(p_cx, InvalidModification);
             return p;
         }
+
+        // Step 4.
         if !self.Characteristic().Service().Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5 - 6: Implement representedCharacteristic internal slot for BluetoothRemoteGATTCharacteristic.
+
+        // TODO: Step 7: Implement the `connection-checking-wrapper` algorithm for BluetoothRemoteGATTServer.
+        // Note: Substeps of Step 7 are implemented in components/bluetooth/lib.rs in writeValue function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::WriteValue(self.get_instance_id(), value, sender)).unwrap();
@@ -131,13 +153,28 @@ impl BluetoothRemoteGATTDescriptorMethods for BluetoothRemoteGATTDescriptor {
 impl AsyncBluetoothListener for BluetoothRemoteGATTDescriptor {
     fn handle_response(&self, response: BluetoothResponse, promise_cx: *mut JSContext, promise: &Rc<Promise>) {
         match response {
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-readvalue
             BluetoothResponse::ReadValue(result) => {
+                // TODO: Step 5.4.1: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.
+
+                // Step 5.4.2.
+                // TODO(#5014): Replace ByteString with ArrayBuffer when it is implemented.
                 let value = ByteString::new(result);
                 *self.value.borrow_mut() = Some(value.clone());
+
+                // Step 5.4.3.
                 promise.resolve_native(promise_cx, &value);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-writevalue
             BluetoothResponse::WriteValue(result) => {
+                // TODO: Step 7.4.1: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.
+
+                // Step 7.4.2.
+                // TODO(#5014): Replace ByteString with an ArrayBuffer wrapped in a DataView.
                 *self.value.borrow_mut() = Some(ByteString::new(result));
+
+                // Step 7.4.3.
+                // TODO: Resolve promise with undefined instead of a value.
                 promise.resolve_native(promise_cx, &());
             },
             _ => promise.reject_error(promise_cx, Error::Type("Something went wrong...".to_owned())),

components/script/dom/bluetoothremotegattserver.rs

@@ -65,19 +65,42 @@ impl BluetoothRemoteGATTServerMethods for BluetoothRemoteGATTServer {
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-connect
     fn Connect(&self) -> Rc<Promise> {
+        // Step 1.
         let p = Promise::new(&self.global());
         let sender = response_async(&p, self);
+
+        // TODO: Step 2: Implement representedDevice internal slot for BluetoothDevice.
+
+        // TODO: Step 3: Check if the UA is currently using the Bluetooth system.
+
+        // TODO: Step 4: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.
+
+        // TODO: Step 5.1 - 5.2: Implement activeAlgorithms, representedDevice internal slots
+        // and the` garbage-collect the connection` algorithm.
+
+        // Note: Steps 5.1.1 and 5.1.3 are in components/bluetooth/lib.rs in the gatt_server_connect function.
+        // Steps 5.2.4 - 5.2.5  are in response function.
         self.get_bluetooth_thread().send(
             BluetoothRequest::GATTServerConnect(String::from(self.Device().Id()), sender)).unwrap();
+        // Step 5: return promise.
         return p;
     }
 
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-disconnect
     fn Disconnect(&self) -> ErrorResult {
+        // TODO: Step 1: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.
+
+        // TODO: Step 2: Check if this.connected is false here too.
         let (sender, receiver) = ipc::channel().unwrap();
         self.get_bluetooth_thread().send(
             BluetoothRequest::GATTServerDisconnect(String::from(self.Device().Id()), sender)).unwrap();
         let server = receiver.recv().unwrap();
+
+        // TODO: Step 3: Implement the `clean up the disconnected device` algorithm.
+
+        // TODO: Step 4: Implement representedDevice internal slot for BluetoothDevice.
+
+        // TODO: Step 5: Implement the `garbage-collect the connection` algorithm.
         match server {
             Ok(connected) => {
                 self.connected.set(connected);
@@ -92,8 +115,12 @@ impl BluetoothRemoteGATTServerMethods for BluetoothRemoteGATTServer {
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-getprimaryservice
     fn GetPrimaryService(&self, service: BluetoothServiceUUID) -> Rc<Promise> {
+        // TODO: Step 1: Implement the Permission API and the allowedServices BluetoothDevice internal slot.
+        // Subsequent steps are relative to https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         let uuid = match BluetoothUUID::service(service) {
             Ok(uuid) => uuid.to_string(),
             Err(e) => {
@@ -101,14 +128,23 @@ impl BluetoothRemoteGATTServerMethods for BluetoothRemoteGATTServer {
                 return p;
             }
         };
+
+        // Step 2.
         if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 3 - 4.
         if !self.Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedDevice internal slot for BluetoothDevice.
+
+        // Note: Steps 6 - 7 are implemented in components/bluetooth/lib.rs in get_primary_service function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetPrimaryService(String::from(self.Device().Id()), uuid, sender)).unwrap();
@@ -118,10 +154,14 @@ impl BluetoothRemoteGATTServerMethods for BluetoothRemoteGATTServer {
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-getprimaryservices
     fn GetPrimaryServices(&self, service: Option<BluetoothServiceUUID>) -> Rc<Promise> {
+        // TODO: Step 1: Implement the Permission API and the allowedServices BluetoothDevice internal slot.
+        // Subsequent steps are relative to https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
         let mut uuid: Option<String> = None;
         if let Some(s) = service {
+            // Step 1.
             uuid = match BluetoothUUID::service(s) {
                 Ok(uuid) => Some(uuid.to_string()),
                 Err(e) => {
@@ -130,16 +170,24 @@ impl BluetoothRemoteGATTServerMethods for BluetoothRemoteGATTServer {
                 }
             };
             if let Some(ref uuid) = uuid {
+                // Step 2.
                 if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
                     p.reject_error(p_cx, Security);
                     return p;
                 }
             }
         };
+
+        // Step 3 - 4.
         if !self.Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedDevice internal slot for BluetoothDevice.
+
+        // Note: Steps 6 - 7 are implemented in components/bluetooth/lib.rs in get_primary_services function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetPrimaryServices(String::from(self.Device().Id()), uuid, sender)).unwrap();
@@ -150,10 +198,17 @@ impl BluetoothRemoteGATTServerMethods for BluetoothRemoteGATTServer {
 impl AsyncBluetoothListener for BluetoothRemoteGATTServer {
     fn handle_response(&self, response: BluetoothResponse, promise_cx: *mut JSContext, promise: &Rc<Promise>) {
         match response {
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-connect
             BluetoothResponse::GATTServerConnect(connected) => {
+                // Step 5.2.4.
                 self.connected.set(connected);
+
+                // Step 5.2.5.
                 promise.resolve_native(promise_cx, self);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-getprimaryservice
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetPrimaryService(service) => {
                 let context = self.device.get().get_context();
                 let mut service_map = context.get_service_map().borrow_mut();
@@ -168,6 +223,9 @@ impl AsyncBluetoothListener for BluetoothRemoteGATTServer {
                 service_map.insert(service.instance_id, MutHeap::new(&bt_service));
                 promise.resolve_native(promise_cx, &bt_service);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-getprimaryservices
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetPrimaryServices(services_vec) => {
                 let mut services = vec!();
                 let context = self.device.get().get_context();

components/script/dom/bluetoothremotegattservice.rs

@@ -95,11 +95,14 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
 
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getcharacteristic
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn GetCharacteristic(&self,
                          characteristic: BluetoothCharacteristicUUID)
                          -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         let uuid = match BluetoothUUID::characteristic(characteristic) {
             Ok(uuid) => uuid.to_string(),
             Err(e) => {
@@ -107,14 +110,23 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
                 return p;
             }
         };
+
+        // Step 2.
         if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 3 - 4.
         if !self.Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedService internal slot for BluetootRemoteGATTService.
+
+        // Note: Steps 6 - 7 are implemented is components/bluetooth/lib.rs in get_characteristic function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetCharacteristic(self.get_instance_id(), uuid, sender)).unwrap();
@@ -123,6 +135,7 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
 
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getcharacteristics
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn GetCharacteristics(&self,
                           characteristic: Option<BluetoothCharacteristicUUID>)
                           -> Rc<Promise> {
@@ -130,6 +143,7 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
         let p_cx = p.global().get_cx();
         let mut uuid: Option<String> = None;
         if let Some(c) = characteristic {
+            // Step 1.
             uuid = match BluetoothUUID::characteristic(c) {
                 Ok(uuid) => Some(uuid.to_string()),
                 Err(e) => {
@@ -138,16 +152,24 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
                 }
             };
             if let Some(ref uuid) = uuid {
+                // Step 2.
                 if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
                     p.reject_error(p_cx, Security);
                     return p;
                 }
             }
         };
+
+        // Step 3 - 4.
         if !self.Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedService internal slot for BluetootRemoteGATTService.
+
+        // Note: Steps 6 - 7 are implemented is components/bluetooth/lib.rs in get_characteristics function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetCharacteristics(self.get_instance_id(), uuid, sender)).unwrap();
@@ -156,11 +178,14 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
 
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getincludedservice
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn GetIncludedService(&self,
                           service: BluetoothServiceUUID)
                           -> Rc<Promise> {
         let p = Promise::new(&self.global());
         let p_cx = p.global().get_cx();
+
+        // Step 1.
         let uuid = match BluetoothUUID::service(service) {
             Ok(uuid) => uuid.to_string(),
             Err(e) => {
@@ -168,14 +193,23 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
                 return p;
             }
         };
+
+        // Step 2.
         if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
             p.reject_error(p_cx, Security);
             return p;
         }
+
+        // Step 3 - 4.
         if !self.Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedService internal slot for BluetootRemoteGATTService.
+
+        // Note: Steps 6 - 7 are implemented is components/bluetooth/lib.rs in get_included_service function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetIncludedService(self.get_instance_id(),
@@ -187,6 +221,7 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
 
     #[allow(unrooted_must_root)]
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getincludedservices
+    // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
     fn GetIncludedServices(&self,
                           service: Option<BluetoothServiceUUID>)
                           -> Rc<Promise> {
@@ -194,6 +229,7 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
         let p_cx = p.global().get_cx();
         let mut uuid: Option<String> = None;
         if let Some(s) = service {
+            // Step 1.
             uuid = match BluetoothUUID::service(s) {
                 Ok(uuid) => Some(uuid.to_string()),
                 Err(e) => {
@@ -202,16 +238,24 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
                 }
             };
             if let Some(ref uuid) = uuid {
+                // Step 2.
                 if uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
                     p.reject_error(p_cx, Security);
                     return p;
                 }
             }
         };
+
+        // Step 3 - 4.
         if !self.Device().Gatt().Connected() {
             p.reject_error(p_cx, Network);
             return p;
         }
+
+        // TODO: Step 5: Implement representedService internal slot for BluetootRemoteGATTService.
+
+        // Note: Steps 6 - 7 are implemented is components/bluetooth/lib.rs in get_included_services function
+        // and in handle_response function.
         let sender = response_async(&p, self);
         self.get_bluetooth_thread().send(
             BluetoothRequest::GetIncludedServices(self.get_instance_id(),
@@ -233,6 +277,9 @@ impl BluetoothRemoteGATTServiceMethods for BluetoothRemoteGATTService {
 impl AsyncBluetoothListener for BluetoothRemoteGATTService {
     fn handle_response(&self, response: BluetoothResponse, promise_cx: *mut JSContext, promise: &Rc<Promise>) {
         match response {
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getcharacteristic
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetCharacteristic(characteristic) => {
                 let context = self.device.get().get_context();
                 let mut characteristic_map = context.get_characteristic_map().borrow_mut();
@@ -258,6 +305,9 @@ impl AsyncBluetoothListener for BluetoothRemoteGATTService {
                 characteristic_map.insert(characteristic.instance_id, MutHeap::new(&bt_characteristic));
                 promise.resolve_native(promise_cx, &bt_characteristic);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getcharacteristics
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetCharacteristics(characteristics_vec) => {
                 let mut characteristics = vec!();
                 let context = self.device.get().get_context();
@@ -292,6 +342,9 @@ impl AsyncBluetoothListener for BluetoothRemoteGATTService {
                 }
                 promise.resolve_native(promise_cx, &characteristics);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getincludedservice
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetIncludedService(service) => {
                 let s =
                     BluetoothRemoteGATTService::new(&self.global(),
@@ -301,6 +354,9 @@ impl AsyncBluetoothListener for BluetoothRemoteGATTService {
                                                     service.instance_id);
                 promise.resolve_native(promise_cx, &s);
             },
+            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattservice-getincludedservices
+            // https://webbluetoothcg.github.io/web-bluetooth/#getgattchildren
+            // Step 7.
             BluetoothResponse::GetIncludedServices(services_vec) => {
                 let s: Vec<Root<BluetoothRemoteGATTService>> =
                     services_vec.into_iter()