Added array support to delta calculations

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@ztimson/utils",
-	"version": "0.26.20",
+	"version": "0.26.26",
 	"description": "Utility library",
 	"author": "Zak Timson",
 	"license": "MIT",

src/database.ts

@@ -14,8 +14,8 @@ class AsyncLock {
 		const res = this.p.then(fn, fn);
 		this.p = res.then(() => {}, () => {});
 		return res;
-}
 	}
+}
 
 export class Database {
 	private schemaLock = new AsyncLock();
@@ -28,7 +28,10 @@ export class Database {
 
 	constructor(public readonly database: string, tables?: (string | TableOptions)[], public version?: number) {
 		this.connection = new Promise((resolve, reject) => {
-			const req = indexedDB.open(this.database, this.version);
+			let req: IDBOpenDBRequest;
+			try { req = indexedDB.open(this.database, this.version); }
+			catch (err) { return reject(err); }
+
 			this.tables = !tables ? [] : tables.map(t => {
 				t = typeof t == 'object' ? t : {name: t};
 				return {...t, name: t.name.toString()};
@@ -37,13 +40,22 @@ export class Database {
 			req.onerror = () => reject(req.error);
 
 			req.onsuccess = () => {
-				const db = req.result;
+				let db: IDBDatabase;
+				try { db = req.result; }
+				catch (err) { return reject(err); }
+
 				const existing = Array.from(db.objectStoreNames);
-				if(!tables) this.tables = existing.map(t => {
+				if(!tables) {
-					const tx = db.transaction(t, 'readonly');
+					this.tables = existing.map(t => {
-					const store = tx.objectStore(t);
+						try {
-					return {name: t, key: <string>store.keyPath};
+							const tx = db.transaction(t, 'readonly');
-				});
+							const store = tx.objectStore(t);
+							return {name: t, key: <string>store.keyPath};
+						} catch {
+							return {name: t}; // 🛡️ fallback
+						}
+					});
+				}
 				const desired = new ASet((tables || []).map(t => typeof t == 'string' ? t : t.name));
 				if(tables && desired.symmetricDifference(new ASet(existing)).length) {
 					db.close();
@@ -58,19 +70,23 @@ export class Database {
 
 			req.onupgradeneeded = () => {
 				this.upgrading = true;
-				const db = req.result;
+				let db: IDBDatabase;
-				const existingTables = new ASet(Array.from(db.objectStoreNames));
+				try { db = req.result; }
-				if(tables) {
+				catch { return; }
-					const desired = new ASet((tables || []).map(t => typeof t == 'string' ? t : t.name));
+				try {
-					existingTables.difference(desired).forEach(name => db.deleteObjectStore(name));
+					const existingTables = new ASet(Array.from(db.objectStoreNames));
-					desired.difference(existingTables).forEach(name => {
+					if(tables) {
-						const t = this.tables.find(findByProp('name', name));
+						const desired = new ASet((tables || []).map(t => typeof t == 'string' ? t : t.name));
-						db.createObjectStore(name, {
+						existingTables.difference(desired).forEach(name => db.deleteObjectStore(name));
-							keyPath: t?.key,
+						desired.difference(existingTables).forEach(name => {
-							autoIncrement: t?.autoIncrement || !t?.key,
+							const t = this.tables.find(findByProp('name', name));
+							db.createObjectStore(name, {
+								keyPath: t?.key,
+								autoIncrement: t?.autoIncrement || !t?.key,
+							});
 						});
-					});
+					}
-				}
+				} catch { }
 			};
 		});
 	}
@@ -79,30 +95,30 @@ export class Database {
 
 	async createTable<K extends IDBValidKey = any, T = any>(table: string | TableOptions): Promise<Table<K, T>> {
 		return this.schemaLock.run(async () => {
-			if (typeof table == 'string') table = { name: table };
+			if(typeof table == 'string') table = { name: table };
 			const conn = await this.connection;
-			if (!this.includes(table.name)) {
+			if(!this.includes(table.name)) {
 				const newDb = new Database(this.database, [...this.tables, table], (this.version ?? 0) + 1);
 				conn.close();
-				Object.assign(this, newDb);
+				this.connection = newDb.connection;
 				await this.connection;
+				Object.assign(this, newDb);
 			}
 			return this.table<K, T>(table.name);
 		});
 	}
 
-
 	async deleteTable(table: string | TableOptions): Promise<void> {
 		return this.schemaLock.run(async () => {
-			if (typeof table == 'string') table = { name: table };
+			if(typeof table == 'string') table = { name: table };
-			if (!this.includes(table.name)) return;
+			if(!this.includes(table.name)) return;
 			const conn = await this.connection;
 			const newDb = new Database(this.database, this.tables.filter(t => t.name != (<TableOptions>table).name), (this.version ?? 0) + 1);
 			conn.close();
-			Object.assign(this, newDb);
+			this.connection = newDb.connection;
 			await this.connection;
+			Object.assign(this, newDb);
 		});
-
 	}
 
 	includes(name: any): boolean {
@@ -126,9 +142,8 @@ export class Table<K extends IDBValidKey = any, T = any> {
 		await this.database.waitForUpgrade();
 		const db = await this.database.connection;
 		const tx = db.transaction(table, readonly ? 'readonly' : 'readwrite');
-		const store = tx.objectStore(table);
 		return new Promise<R>((resolve, reject) => {
-			const request = fn(store);
+			const request = fn(tx.objectStore(table));
 			request.onsuccess = () => resolve(request.result as R);
 			request.onerror = () => reject(request.error);
 		});
@@ -168,7 +183,7 @@ export class Table<K extends IDBValidKey = any, T = any> {
 
 	put(value: T, key?: string): Promise<void> {
 		return this.tx(this.name, store => {
-			if (store.keyPath) return store.put(value);
+			if(store.keyPath) return store.put(value);
 			return store.put(value, key);
 		});
 	}

src/misc.ts

@@ -1,9 +1,21 @@
 import {PathEvent} from './path-events.ts';
 import {md5} from './string';
 
+/**
+ * Compare version numbers
+ * @param {string} target
+ * @param {string} vs
+ * @return {number} -1 = target is lower, 0 = equal, 1 = higher
+ */
+export function compareVersions(target: string, vs: string): -1 | 0 | 1 {
+	const [tMajor, tMinor, tPatch] = target.split('.').map(v => +v.replace(/[^0-9]/g, ''));
+	const [vMajor, vMinor, vPatch] = vs.split('.').map(v => +v.replace(/[^0-9]/g, ''));
+	return (tMajor > vMajor || tMinor > vMinor || tPatch > vPatch) ? 1 :
+		(tMajor < vMajor || tMinor < vMinor || tPatch < vPatch) ? -1 : 0;
+}
+
 /**
  * Escape any regex special characters to avoid misinterpretation during search
- *
  * @param {string} value String which should be escaped
  * @return {string} New escaped sequence
  */

src/objects.ts

@@ -1,3 +1,58 @@
+export type Delta = { [key: string]: any | Delta | null };
+
+/**
+ * Applies deltas in order to modify `target`.
+ * @param target - Object to mutate
+ * @param deltas - List of deltas to apply
+ * @returns Mutated target
+ */
+export function applyDeltas(target: any, deltas: Delta[]): any {
+	for(const delta of deltas) {
+		for(const [key, value] of Object.entries(delta)) {
+			if(value === null) {
+				delete target[key]; // Remove
+			} else if(Array.isArray(value)) {
+				target[key] = [...value]; // Array
+			} else if(typeof value === 'object') {
+				if(typeof target[key] !== 'object' || Array.isArray(target[key]) || !target[key])
+					target[key] = {}; // Nested
+				applyDeltas(target[key], [value]); // Recurse
+			} else {
+				target[key] = value; // Primitive
+			}
+		}
+	}
+	return target;
+}
+
+/**
+ * Creates a nested delta that reverts `target` back to `old`.
+ * @param old - Original object
+ * @param target - Modified object
+ * @returns Delta to revert changes
+ */
+export function calcDelta(old: any, target: any): Delta {
+	const delta: Delta = {};
+	const keys = new Set([...Object.keys(old || {}), ...Object.keys(target || {})]);
+	for(const key of keys) {
+		const val1 = old?.[key];
+		const val2 = target?.[key];
+		if(!(key in target)) {
+			delta[key] = val1; // Removed
+		} else if(!(key in old)) {
+			delta[key] = null; // Added
+		} else if(Array.isArray(val1) || Array.isArray(val2)) {
+			if(JSON.stringify(val1) !== JSON.stringify(val2)) delta[key] = val1; // Array
+		} else if(typeof val1 === 'object' && typeof val2 === 'object' && val1 && val2) {
+			const nested = calcDelta(val1, val2);
+			if(Object.keys(nested).length) delta[key] = nested; // Nested
+		} else if(val1 !== val2) {
+			delta[key] = val1; // Modified
+		}
+	}
+	return delta;
+}
+
 /**
  * Removes any null values from an object in-place
  *