From 78cefb07767628425b85b0b16423761230a34218 Mon Sep 17 00:00:00 2001
From: Cadence Ember <cloudrac3r@vivaldi.net>
Date: Wed, 29 Jul 2020 15:32:04 +1200
Subject: [PATCH] Fix simultaneous accesses to inflight RequestCache

---
 src/lib/cache.js      | 14 ++++++--------
 src/lib/collectors.js |  7 -------
 2 files changed, 6 insertions(+), 15 deletions(-)

diff --git a/src/lib/cache.js b/src/lib/cache.js
index b683def..fbdb280 100644
--- a/src/lib/cache.js
+++ b/src/lib/cache.js
@@ -92,7 +92,7 @@ class TtlCache {
 }
 
 /**
- * @extends TtlCache<T>
+ * @extends TtlCache<Promise<T>>
  * @template T
  */
 class RequestCache extends TtlCache {
@@ -110,14 +110,12 @@ class RequestCache extends TtlCache {
 	 */
 	getOrFetch(key, callback) {
 		this.cleanKey(key)
-		if (this.cache.has(key)) return Promise.resolve({result: this.get(key), fromCache: true})
-		else {
-			const pending = callback().then(result => {
-				this.set(key, result)
-				return {result, fromCache: false}
-			})
+		if (this.cache.has(key)) {
+			return this.getWithoutClean(key).then(result => ({result, fromCache: true}))
+		} else {
+			const pending = callback()
 			this.set(key, pending)
-			return pending
+			return pending.then(result => ({result, fromCache: false}))
 		}
 	}
 
diff --git a/src/lib/collectors.js b/src/lib/collectors.js
index 31c70ce..6e23fd1 100644
--- a/src/lib/collectors.js
+++ b/src/lib/collectors.js
@@ -400,19 +400,12 @@ function fetchShortcodeData(shortcode) {
 	const p = new URLSearchParams()
 	p.set("query_hash", constants.external.shortcode_query_hash)
 	p.set("variables", JSON.stringify({shortcode}))
-	let status
 	return requestCache.getOrFetchPromise("shortcode/"+shortcode, () => {
 		return switcher.request("post_graphql", `https://www.instagram.com/graphql/query/?${p.toString()}`, async res => {
-			status = res.status
 			if (res.status === 429) throw constants.symbols.RATE_LIMITED
 		}).then(res => res.json()).then(root => {
 			/** @type {import("./types").TimelineEntryN3} */
 			const data = root.data.shortcode_media
-			if (data && !data.__typename) { // empty data? that's really weird.
-				console.error(`Shortcode request ${shortcode} gave empty data object. status: ${status}, root:`)
-				console.error(root)
-				console.error("will just proceed to crash as normal.")
-			}
 			if (data == null) {
 				// the thing doesn't exist
 				throw constants.symbols.NOT_FOUND