Replace Object#hasOwnProperty with Object.hasOwn

Change most, but not all usages. This is mostly to please the linter,
but Object.hasOwn is also slightly shorter, especially when compared to
the proper form, Object.prototype.hasOwnProperty...

src/js/core/state_manager.js

@@ -69,7 +69,7 @@ export class StateManager {
 
             // Remove all references
             for (const stateKey in this.currentState) {
-                if (this.currentState.hasOwnProperty(stateKey)) {
+                if (Object.hasOwn(this.currentState, stateKey)) {
                     delete this.currentState[stateKey];
                 }
             }

src/js/game/hud/parts/building_placer_logic.js

@@ -159,7 +159,7 @@ export class HUDBuildingPlacerLogic extends BaseHUDPart {
             return this.currentBaseRotationGeneral;
         }
         const metaBuilding = this.currentMetaBuilding.get();
-        if (metaBuilding && this.preferredBaseRotations.hasOwnProperty(metaBuilding.getId())) {
+        if (metaBuilding && Object.hasOwn(this.preferredBaseRotations, metaBuilding.getId())) {
             return this.preferredBaseRotations[metaBuilding.getId()];
         } else {
             return this.currentBaseRotationGeneral;

src/js/game/root.js

@@ -224,8 +224,8 @@ export class GameRoot {
         }
 
         // Finally free all properties
-        for (let prop in this) {
+        for (const prop in this) {
-            if (this.hasOwnProperty(prop)) {
+            if (Object.hasOwn(this, prop)) {
                 delete this[prop];
             }
         }

src/js/profile/application_settings.js

@@ -375,7 +375,7 @@ export class ApplicationSettings extends ReadWriteProxy {
      * @param {string} key
      */
     getSetting(key) {
-        assert(this.getAllSettings().hasOwnProperty(key), "Setting not known: " + key);
+        assert(Object.hasOwn(this.getAllSettings(), key), "Setting not known: " + key);
         return this.getAllSettings()[key];
     }
 

src/js/savegame/serialization.js

@@ -18,11 +18,11 @@ import {
     TypeNumber,
     TypePair,
     TypePositiveInteger,
+    TypePositiveIntegerOrString,
     TypePositiveNumber,
     TypeString,
     TypeStructuredObject,
     TypeVector,
-    TypePositiveIntegerOrString,
 } from "./serialization_data_types";
 
 /**
@@ -239,12 +239,9 @@ export class BasicSerializableObject {
  */
 export function serializeSchema(obj, schema, mergeWith = {}) {
     for (const key in schema) {
-        if (!obj.hasOwnProperty(key)) {
+        if (!Object.hasOwn(obj, key)) {
             logger.error("Invalid schema, property", key, "does not exist on", obj, "(schema=", schema, ")");
-            assert(
+            assert(false, "serialization: invalid schema, property does not exist on object: " + key);
-                obj.hasOwnProperty(key),
-                "serialization: invalid schema, property does not exist on object: " + key
-            );
         }
         if (!schema[key]) {
             assert(false, "Invalid schema (bad key '" + key + "'): " + JSON.stringify(schema));
@@ -292,7 +289,7 @@ export function deserializeSchema(obj, schema, data, baseclassErrorResult = null
     }
 
     for (const key in schema) {
-        if (!data.hasOwnProperty(key)) {
+        if (!Object.hasOwn(data, key)) {
             logger.error("Data", data, "does not contain", key, "(schema:", schema, ")");
             return "Missing key in schema: " + key + " of class " + obj.constructor.name;
         }
@@ -325,7 +322,7 @@ export function deserializeSchema(obj, schema, data, baseclassErrorResult = null
  */
 export function verifySchema(schema, data) {
     for (const key in schema) {
-        if (!data.hasOwnProperty(key)) {
+        if (!Object.hasOwn(data, key)) {
             logger.error("Data", data, "does not contain", key, "(schema:", schema, ")");
             return "verify: missing key required by schema in stored data: " + key;
         }
@@ -352,7 +349,7 @@ export function extendSchema(base, newOne) {
     /** @type {Schema} */
     const result = Object.assign({}, base);
     for (const key in newOne) {
-        if (result.hasOwnProperty(key)) {
+        if (Object.hasOwn(result, key)) {
             logger.error("Extend schema got duplicate key:", key);
             continue;
         }