README.md

@@ -1,6 +1,5 @@
 # lmlfc-bttv
 
-- install deps: `yarn`
-- more verbose but same: `yarn install --production=false`
-- compile extension (into "dist" dir): `yarn build`
-- pack "dist" dir (runs web-ext): `yarn build-ext`
+- install deps `yarn install --production=false`
+- make "dist" dir: `yarn build`
+- pack "dist" dir: `yarn build-ext`

package.json

@@ -4,8 +4,8 @@
   "author": "Jörn-Michael Miehe <joern-michael.miehe@lenaisten.de>",
   "license": "MIT",
   "scripts": {
-    "build-debug": "webpack --mode=development",
-    "build": "webpack --mode=production",
+    "build": "webpack --mode=development",
+    "build-release": "webpack --mode=production",
     "lint-ext": "web-ext lint --source-dir=dist",
     "build-ext": "web-ext build --source-dir=dist --artifacts-dir=dist --overwrite-dest"
   },

src/bttv_api.ts

@@ -13,9 +13,12 @@ type BTTV_Emote = {
  * Query BTTV API for an emote graphic
  *
  * @param code string associated with the emote graphic (often called "emote" itself)
- * @returns `null` iff no emote found or error, else URL to a BTTV emote graphic
+ * @returns `null` iff no emote found or error,
+ * else `[code, url]` tuple where `url` is the URL to a BTTV emote graphic
  */
-export async function bttv_get_url(code: string): Promise<string | null> {
+export async function bttv_get_url(
+  code: string,
+): Promise<[string, string] | null> {
   // search for emotes
   const res = await fetch(
     `https://api.betterttv.net/3/emotes/shared/search?query=${code}&offset=0&limit=50`,
@@ -34,5 +37,8 @@ export async function bttv_get_url(code: string): Promise<string | null> {
   if (matches.length <= 0) return null;
 
   // return first emote's URL
-  return `//cdn.betterttv.net/emote/${matches[0].id}/1x.${matches[0].imageType}`;
+  return [
+    code,
+    `//cdn.betterttv.net/emote/${matches[0].id}/1x.${matches[0].imageType}`,
+  ];
 }

src/helpers.ts

@@ -1,3 +1,8 @@
+/**
+ * Async function mapping some `input` to an `[input, output]` tuple or a `null` if no output exists
+ */
+type MapFunction<In, Out> = (input: In) => Promise<[In, Out] | null>;
+
 /**
  * Concurrently create some mapping of input to output elements.
  *
@@ -7,13 +12,13 @@
  */
 export async function map_concurrent<In, Out>(
   inputs: Iterable<In>,
-  map_fn: (input: In) => Promise<Out | null>,
-): Promise<Map<In, Out | null>> {
+  map_fn: MapFunction<In, Out>,
+): Promise<Map<In, Out>> {
   // apply map_fn to inputs
-  const outputs = await Promise.all([...inputs].map((input) => map_fn(input)));
+  const queue = [...inputs].map((input) => map_fn(input));
 
-  // create map object
-  return new Map<In, Out | null>(
-    [...inputs].map((input, index) => [input, outputs[index]]),
+  // wait for calls to finish
+  return new Map<In, Out>(
+    (await Promise.all(queue)).filter((job): job is [In, Out] => job !== null),
   );
 }

src/main.ts

@@ -24,13 +24,13 @@ async function process_text(text: string): Promise<string> {
   for (const emote of matches.reverse()) {
     const [match, code] = emote;
 
-    // ensure emote exists
+    if (!emotes.has(code)) continue;
+    // emote exists
     const url = emotes.get(code);
-    if (url == null) continue;
 
-    // ensure position in input string is known
+    if (emote.index == undefined) continue;
+    // position in input string is known
     const index = emote.index;
-    if (index == undefined) continue;
 
     text =
       text.substring(0, index) +