Add types to promisify-port.js (#127)

lib/promisify-port.js

@@ -1,5 +1,16 @@
+/**
+ * Allows to treat a pair of ports as one promise.
+ * It sends a message into `sendTrough` and resolves the promise with the first "response" data on `subscribeTo`.
+ * @template DataIn,DataOut
+ * @param {import("./types/promisify-port").PortsToPromise<DataIn, DataOut>} obj
+ * @returns {PromiseLike<DataOut>}
+ */
 function promisifyPort({subscribeTo, sendThrough, data}) {
   return new Promise((resolve) => {
+    /**
+     * @param {DataOut} result
+     * @returns void
+     */
     const handler = (result) => {
       subscribeTo.unsubscribe(handler);
       resolve(result);

lib/types/promisify-port.d.ts

@@ -0,0 +1,16 @@
+export type PortsToPromise<DataIn, DataOut> = {
+  subscribeTo: PortFromElm<DataOut>;
+  sendThrough: PortToElm<DataIn>;
+  data: DataIn;
+};
+
+export type PortFromElm<DataOut> = {
+  subscribe: CallbackFn<DataOut>;
+  unsubscribe: CallbackFn<DataOut>;
+};
+
+type CallbackFn<T> = (cb: (data: T) => void) => void;
+
+export type PortToElm<DataIn> = {
+  send: (data: DataIn) => void;
+};

tsconfig.no-implicit-any.json

@@ -11,6 +11,7 @@
     "lib/hash.js",
     "lib/help.js",
     "lib/os-helpers.js",
+    "lib/promisify-port.js",
     "jest.config.js"
   ]
 }