Fix the awaitable collect() calls.

In case if non-native promises are used, the Promise object won't be instanceof Promise. That's still valid in JS, as Promise is something that implements then(). It's always safe to cast a maybe-promise into native Promise with Promise.resolve().

Author: farcaller

lib/counter.js

@@ -108,8 +108,7 @@ class Counter extends Metric {
 
 	async get() {
 		if (this.collect) {
-			const v = this.collect();
-			if (v instanceof Promise) await v;
+			const v = await Promise.resolve(this.collect());
 		}
 
 		return {

lib/gauge.js

@@ -107,8 +107,7 @@ class Gauge extends Metric {
 
 	async get() {
 		if (this.collect) {
-			const v = this.collect();
-			if (v instanceof Promise) await v;
+			const v = await Promise.resolve(this.collect());
 		}
 		return {
 			help: this.help,

lib/histogram.js

@@ -107,8 +107,7 @@ class Histogram extends Metric {
 
 	async getForPromString() {
 		if (this.collect) {
-			const v = this.collect();
-			if (v instanceof Promise) await v;
+			const v = await Promise.resolve(this.collect());
 		}
 		const data = Object.values(this.hashMap);
 		const values = data

lib/summary.js

@@ -50,8 +50,7 @@ class Summary extends Metric {
 
 	async get() {
 		if (this.collect) {
-			const v = this.collect();
-			if (v instanceof Promise) await v;
+			const v = await Promise.resolve(this.collect());
 		}
 		const hashKeys = Object.keys(this.hashMap);
 		const values = [];