move autobind and debouncePromise to common/utils (#1081)

Signed-off-by: Sebastian Malton <sebastian@malton.name>

src/common/utils/autobind.ts

@@ -0,0 +1,44 @@
+// Decorator for binding class methods
+// Can be applied to class or single method as @autobind()
+type Constructor<T = {}> = new (...args: any[]) => T;
+
+export function autobind() {
+  return function (target: Constructor | object, prop?: string, descriptor?: PropertyDescriptor) {
+    if (target instanceof Function) return bindClass(target);
+    else return bindMethod(target, prop, descriptor);
+  }
+}
+
+function bindClass<T extends Constructor>(constructor: T) {
+  const proto = constructor.prototype;
+  const descriptors = Object.getOwnPropertyDescriptors(proto);
+
+  const skipMethod = (methodName: string) => {
+    return methodName === "constructor"
+      || typeof descriptors[methodName].value !== "function";
+  };
+
+  Object.keys(descriptors).forEach(prop => {
+    if (skipMethod(prop)) return;
+    const boundDescriptor = bindMethod(proto, prop, descriptors[prop]);
+    Object.defineProperty(proto, prop, boundDescriptor);
+  })
+}
+
+function bindMethod(target: object, prop?: string, descriptor?: PropertyDescriptor) {
+  if (!descriptor || typeof descriptor.value !== "function") {
+    throw new Error(`@autobind() must be used on class or method only`)
+  }
+  const { value: func, enumerable, configurable } = descriptor;
+  const boundFunc = new WeakMap<object, Function>();
+
+  return Object.defineProperty(target, prop, {
+    enumerable,
+    configurable,
+    get() {
+      if (this === target) return func; // direct access from prototype
+      if (!boundFunc.has(this)) boundFunc.set(this, func.bind(this));
+      return boundFunc.get(this);
+    }
+  });
+}

src/common/utils/debouncePromise.ts

@@ -0,0 +1,9 @@
+// Debouncing promise evaluation
+
+export function debouncePromise<T, F extends any[]>(func: (...args: F) => T | Promise<T>, timeout = 0): (...args: F) => Promise<T> {
+  let timer: NodeJS.Timeout;
+  return (...params: any[]) => new Promise((resolve, reject) => {
+    clearTimeout(timer);
+    timer = setTimeout(() => resolve(func.apply(this, params)), timeout);
+  });
+}

src/common/utils/index.ts

@@ -1,7 +1,14 @@
-// Common utils (main/renderer)
+// Common utils (main OR renderer)
 
+export * from "./app-version"
+export * from "./autobind"
 export * from "./base64"
 export * from "./camelCase"
+export * from "./cloneJson"
+export * from "./debouncePromise"
+export * from "./defineGlobal"
+export * from "./getRandId"
 export * from "./splitArray"
-export * from "./getRandId"
+export * from "./saveToAppFiles"
+export * from "./singleton"
 export * from "./cloneJson"