refactor: Drop manual default implementations

in favor of the corresponding macro.

(cherry picked from commit 967d100042c363b1788fe9439f74901cabd83363)

lib/src/server/session.rs

@@ -51,20 +51,12 @@ pub enum ServerUserIdentityToken {
     Invalid(ExtensionObject),
 }
 
+#[derive(Default)]
 pub struct SessionManager {
     pub sessions: HashMap<NodeId, Arc<RwLock<Session>>>,
     pub sessions_terminated: bool,
 }
 
-impl Default for SessionManager {
-    fn default() -> Self {
-        Self {
-            sessions: HashMap::new(),
-            sessions_terminated: false,
-        }
-    }
-}
-
 impl SessionManager {
     pub fn len(&self) -> usize {
         self.sessions.len()

lib/src/server/session_diagnostics.rs

@@ -9,22 +9,13 @@ use super::{
 
 /// This object tracks session diagnostics for exposure through the address space
 
+#[derive(Default)]
 pub(crate) struct SessionDiagnostics {
     total_request_count: u32,
     unauthorized_request_count: u32,
     service_counters: HashMap<&'static str, ServiceCounterDataType>,
 }
 
-impl Default for SessionDiagnostics {
-    fn default() -> Self {
-        Self {
-            total_request_count: 0,
-            unauthorized_request_count: 0,
-            service_counters: HashMap::new(),
-        }
-    }
-}
-
 impl SessionDiagnostics {
     /// Registers a session object
     pub(crate) fn register_session(&self, session: &Session, address_space: &mut AddressSpace) {

lib/src/types/service_types/impls.rs

@@ -19,9 +19,8 @@ use crate::types::{
         enums::DeadbandType, AnonymousIdentityToken, ApplicationDescription, ApplicationType,
         Argument, CallMethodRequest, DataChangeFilter, DataChangeTrigger, DataSetFieldFlags,
         EndpointDescription, MessageSecurityMode, MonitoredItemCreateRequest, MonitoringMode,
-        MonitoringParameters, ReadValueId, ServerDiagnosticsSummaryDataType,
-        ServiceCounterDataType, ServiceFault, SignatureData, UserNameIdentityToken,
-        UserTokenPolicy, UserTokenType,
+        MonitoringParameters, ReadValueId, ServiceCounterDataType, ServiceFault, SignatureData,
+        UserNameIdentityToken, UserTokenPolicy, UserTokenType,
     },
     status_codes::StatusCode,
     string::UAString,
@@ -346,25 +345,6 @@ impl Into<CallMethodRequest> for (NodeId, NodeId, Option<Vec<Variant>>) {
     }
 }
 
-impl Default for ServerDiagnosticsSummaryDataType {
-    fn default() -> Self {
-        ServerDiagnosticsSummaryDataType {
-            server_view_count: 0,
-            current_session_count: 0,
-            cumulated_session_count: 0,
-            security_rejected_session_count: 0,
-            rejected_session_count: 0,
-            session_timeout_count: 0,
-            session_abort_count: 0,
-            current_subscription_count: 0,
-            cumulated_subscription_count: 0,
-            publishing_interval_count: 0,
-            security_rejected_requests_count: 0,
-            rejected_requests_count: 0,
-        }
-    }
-}
-
 impl<'a> From<&'a str> for EndpointDescription {
     fn from(v: &'a str) -> Self {
         EndpointDescription::from((
@@ -477,15 +457,6 @@ impl From<(&str, DataTypeId)> for Argument {
     }
 }
 
-impl Default for ServiceCounterDataType {
-    fn default() -> Self {
-        Self {
-            total_count: 0,
-            error_count: 0,
-        }
-    }
-}
-
 impl ServiceCounterDataType {
     pub fn success(&mut self) {
         self.total_count += 1;

lib/src/types/service_types/server_diagnostics_summary_data_type.rs

@@ -12,7 +12,7 @@ use crate::types::{
 };
 use std::io::{Read, Write};
 
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 #[serde(rename_all = "PascalCase")]
 pub struct ServerDiagnosticsSummaryDataType {
     pub server_view_count: u32,

lib/src/types/service_types/service_counter_data_type.rs

@@ -12,7 +12,7 @@ use crate::types::{
 };
 use std::io::{Read, Write};
 
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Default)]
 pub struct ServiceCounterDataType {
     pub total_count: u32,
     pub error_count: u32,

lib/src/types/variant.rs

@@ -36,9 +36,10 @@ use crate::types::{
 ///
 /// As variants may be passed around a lot on the stack, Boxes are used for more complex types to
 /// keep the size of this type down a bit, especially when used in arrays.
-#[derive(PartialEq, Debug, Clone)]
+#[derive(PartialEq, Debug, Clone, Default)]
 pub enum Variant {
     /// Empty type has no value. It is equivalent to a Null value (part 6 5.1.6)
+    #[default]
     Empty,
     /// Boolean
     Boolean(bool),
@@ -669,12 +670,6 @@ impl BinaryEncoder<Variant> for Variant {
     }
 }
 
-impl Default for Variant {
-    fn default() -> Self {
-        Variant::Empty
-    }
-}
-
 /// This implementation is mainly for debugging / convenience purposes, to eliminate some of the
 /// noise in common types from using the Debug trait.
 impl fmt::Display for Variant {

tools/schema/types.js

@@ -60,7 +60,7 @@ function makeImportLookupMap(import_map) {
 }
 
 // Types that will be marked as Default constructable
-const DEFAULT_TYPES = ["ReadValueId", ];
+const DEFAULT_TYPES = ["ReadValueId", "ServerDiagnosticsSummaryDataType", "ServiceCounterDataType"];
 
 // Types that will be marked as JSON serializable. Serialization is for pubsub, and debugging purposes
 const JSON_SERIALIZED_TYPES = [