more jsDocs + strict equality for strings

src/Umbraco.Web.UI.Client/src/libs/observable-api/states/string-state.ts

@@ -1,5 +1,5 @@
 import type { MappingFunction, MemoizationFunction } from '../types/index.js';
-import { createObservablePart } from '../utils/index.js';
+import { createObservablePart, strictEqualityMemoization } from '../utils/index.js';
 import { UmbBasicState } from './basic-state.js';
 
 /**
@@ -17,6 +17,6 @@ export class UmbStringState<T> extends UmbBasicState<T | string> {
 		mappingFunction: MappingFunction<T | string, ReturnType>,
 		memoizationFunction?: MemoizationFunction<ReturnType>,
 	) {
-		return createObservablePart(this._subject, mappingFunction, memoizationFunction);
+		return createObservablePart(this._subject, mappingFunction, memoizationFunction ?? strictEqualityMemoization);
 	}
 }

src/Umbraco.Web.UI.Client/src/libs/observable-api/utils/deep-freeze.function.ts

@@ -1,3 +1,14 @@
+/**
+ * Deep freeze an object and all its properties.
+ * @param {T} inObj - The object to deep freeze.
+ * @returns {T} - The deep frozen object.
+ * @description - Deep freezes an object and all its properties.
+ * @example <caption>Example of deep freezing an object.</caption>
+ * const myObject = {a: 1, b: {c: 2}};
+ * const frozenObject = deepFreeze(myObject);
+ * frozenObject.a = 3; // Throws an error.
+ * frozenObject.b.c = 4; // Throws an error.
+ */
 export const deepFreeze = Object.freeze(function deepFreezeImpl<T>(inObj: T): T {
 	if (inObj != null && typeof inObj === 'object') {
 		Object.freeze(inObj);

src/Umbraco.Web.UI.Client/src/libs/observable-api/utils/index.ts

@@ -3,9 +3,10 @@ export * from './create-observable-part.function.js';
 export * from './deep-freeze.function.js';
 export * from './default-memoization.function.js';
 export * from './filter-frozen-array.function.js';
-export * from './merge-observables.function.js';
 export * from './json-string-comparison.function.js';
+export * from './merge-observables.function.js';
 export * from './observe-multiple.function.js';
 export * from './partial-update-frozen-array.function.js';
 export * from './push-to-unique-array.function.js';
 export * from './simple-hash-code.function.js';
+export * from './strict-equality-memoization.function.js';

src/Umbraco.Web.UI.Client/src/libs/observable-api/utils/merge-observables.function.ts

@@ -37,7 +37,7 @@ export function mergeObservables<
 ): Observable<R> {
 	return combineLatest(sources).pipe(
 		map(mergeFunction as MappingFunction<unknown[], R>),
-		distinctUntilChanged(memoizationFunction || defaultMemoization),
+		distinctUntilChanged(memoizationFunction ?? defaultMemoization),
 		shareReplay(1),
 	);
 }

src/Umbraco.Web.UI.Client/src/libs/observable-api/utils/strict-equality-memoization.function.ts

@@ -0,0 +1,11 @@
+/**
+ * @export
+ * @method strictEqualityMemoization
+ * @param {unknown} previousValue - The previous value to compare.
+ * @param {unknown} currentValue - The current value to compare.
+ * @returns {boolean} - Returns true if the values are identical.
+ * @description - Compares the two values using strict equality.
+ */
+export function strictEqualityMemoization(previousValue: unknown, currentValue: unknown): boolean {
+	return previousValue === currentValue;
+}