Use pseudo-build process

I'm not particularly proud of this solution as it requires manual
intervention to run tests.
Still searching for a way to very simply bundle the entrypoint functions
such that they are the only ones detected by GAS. The bundlers I've
tried thus far (esbuild, rollup) add too much boilerplate and expose
additional functions that GAS shouldn't care about.
This works for now, but I'll continue looking for a tool suited for the
above (perhaps creating my own if necessary).

Author: Jules Amosah

.clasp.json

@@ -1,4 +1,5 @@
 {
   "$schema": "http://json.schemastore.org/clasp",
-  "scriptId": "1R8lHinD4Gc2PL2MLqncB7lV_SpHy33b-Ay3OejWnTTXmsf4C9aYX1ZAh"
+  "scriptId": "1R8lHinD4Gc2PL2MLqncB7lV_SpHy33b-Ay3OejWnTTXmsf4C9aYX1ZAh",
+  "rootDir": "dist"
 }

.claspignore

@@ -1,13 +1,23 @@
-# GMail Scripts
+# Gmail Scripts
 
 [![clasp](https://img.shields.io/badge/built%20with-clasp-4285f4.svg)](https://github.com/google/clasp)
 
-These are just some basic automated tasks created using [Google Apps Script](https://www.google.com/script/start/). They are described below.
+These are just some basic automated tasks created using [Google Apps Script (GAS)](https://www.google.com/script/start/). They are described below.
 
-## Delete Old Labels
+## Functions
+
+### Delete Old Labels
 
 I use labels to hang on to emails that I could need again in the immediate future. After months, however, I usually don't still need them. This function deletes emails by label older than a certain threshold (for my use case: 90 days).
 
-## Mark Deleted As Read
+### Mark Deleted As Read
 
 Sometimes I delete emails without opening them (you know the type). I run this function periodically to mark all unread deleted emails as read.
+
+## Building
+
+Run `npm run build`. 'Course, all this does right now is copy `main.js` and `appsscript.json` into the `dist/` folder. Haven't yet figured out a satisfactory way to bundle the source code for GAS, but am open to suggestions.
+
+## Testing
+
+Run `npm test`. Note that you will need to uncomment the export at the end of `main.js` for the tests to run properly.

README.md

@@ -1,29 +1,54 @@
+// Using IIFE to prevent GAS from picking up these utility functions
 const bulkThreadAction = (() => {
+  /**
+ * Splits the given array into subarrays of the given size
+ * @param {unknown[]} array
+ * @param {number} chunkSize
+ * @returns {unknown[][]}
+ */
   const chunk = (array, chunkSize) =>
     array.reduce((array2, thread, idx) =>
       idx % chunkSize === 0
         ? [...array2, [thread]]
         : [...array2.slice(0, -1), [...array2.slice(-1)[0], thread]], []);
 
+  /** @typedef {(threads: unknown[]) => void} threadAction */
+
+  /**
+ * GmailApp will error if its thread functions are called with more than 100 threads at a time.
+ * This wrapper ensures threads are appropriately split to prevent said error.
+ * @param {string} query
+ * @param {threadAction} action
+ * @returns {void}
+ */
   function bulkThreadAction(query, action) {
+    console.info(`Searching for threads matching: [${query}]`);
+    /** @type {unknown[]} */
     const targetThreads = GmailApp.search(query);
+
     if (targetThreads.length === 0) {
       console.info("No threads to operate on");
       return;
     }
+
+    console.info(`Calling ${action.name} with ${targetThreads.length} threads`);
+
     if (targetThreads.length <= 100) {
-      console.info("<= 100 threads; not chunking");
+      console.info("Not chunking; <= 100 threads");
       action(targetThreads);
       return;
     }
-    console.info(`Chunking ${targetThreads.length} threads`);
+
     const chunkedThreads = chunk(targetThreads, 100);
+    console.info(`Split threads into ${chunkedThreads.length} chunks`);
     chunkedThreads.forEach((threadChunk) => action(threadChunk));
   }
-
   return bulkThreadAction;
 })();
 
+/**
+ * Deletes labels of interest older than 90 days
+ */
 function deleteOldLabels() {
   const ninetyDaysAgo = new Date();
   ninetyDaysAgo.setDate(ninetyDaysAgo.getDate() - 90);
@@ -38,7 +63,14 @@ function deleteOldLabels() {
   );
 }
 
-const markDeletedAsRead = () =>
+/**
+ * Marks deleted threads as read
+ */
+function markDeletedAsRead() {
   bulkThreadAction("is:unread in:trash", GmailApp.markThreadsRead);
+}
 
-export { bulkThreadAction };
+// (Until I figure out a way to bundle this file
+// that isn't over-engineered and unreadable)
+// Uncomment to run tests
+// export { bulkThreadAction };

main.js

@@ -8,7 +8,7 @@ const query = "test";
 const search = stub();
 const threadAction = fake();
 
-const act = bulkThreadAction.bind(null, query, threadAction);
+const act = () => bulkThreadAction(query, threadAction);
 
 global.GmailApp = {
   search,