From b0026ed9fc863727fc4c958641582caa08bb03e2 Mon Sep 17 00:00:00 2001
From: Viktor Polishchuk <viktorpo@wix.com>
Date: Mon, 22 Apr 2019 16:23:05 +0300
Subject: [PATCH 1/2] Avoiding recreating logger for the namespace which has
 been already created. Fix memory leak for a fixed number of categories. For
 dynamic categories method destroy is still required. #678

---
 src/common.js | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/src/common.js b/src/common.js
index 2f82b8dc..de1ca025 100644
--- a/src/common.js
+++ b/src/common.js
@@ -19,8 +19,9 @@ function setup(env) {
 
 	/**
 	* Active `debug` instances.
+	* @type {Object<String, Function>}
 	*/
-	createDebug.instances = [];
+	createDebug.instances = {};
 
 	/**
 	* The currently active debug mode names, and names to skip.
@@ -62,7 +63,11 @@ function setup(env) {
 	* @api public
 	*/
 	function createDebug(namespace) {
-		let prevTime;
+		let prevTime, value = createDebug.instances[namespace];
+
+		if (!!value) {
+			return value;
+		}
 
 		function debug(...args) {
 			// Disabled?
@@ -74,8 +79,7 @@ function setup(env) {
 
 			// Set `diff` timestamp
 			const curr = Number(new Date());
-			const ms = curr - (prevTime || curr);
-			self.diff = ms;
+			self.diff = curr - (prevTime || curr);
 			self.prev = prevTime;
 			self.curr = curr;
 			prevTime = curr;
@@ -128,15 +132,14 @@ function setup(env) {
 			createDebug.init(debug);
 		}
 
-		createDebug.instances.push(debug);
+		createDebug.instances[namespace] = debug;
 
 		return debug;
 	}
 
 	function destroy() {
-		const index = createDebug.instances.indexOf(this);
-		if (index !== -1) {
-			createDebug.instances.splice(index, 1);
+		if (createDebug.instances.hasOwnProperty(this.namespace)) {
+			delete createDebug.instances[this.namespace];
 			return true;
 		}
 		return false;
@@ -180,8 +183,10 @@ function setup(env) {
 			}
 		}
 
-		for (i = 0; i < createDebug.instances.length; i++) {
-			const instance = createDebug.instances[i];
+		const keys = Object.keys(createDebug.instances);
+
+		for (i = 0; i < keys.length; i++) {
+			const instance = createDebug.instances[keys[i]];
 			instance.enabled = createDebug.enabled(instance.namespace);
 		}
 	}

From 54d4acc58d324879a5a36ad7984fa96a8c354fe8 Mon Sep 17 00:00:00 2001
From: Viktor Polishchuk <viktorpo@wix.com>
Date: Tue, 30 Apr 2019 10:12:59 +0300
Subject: [PATCH 2/2] Fixed lint errors #678

---
 src/common.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/common.js b/src/common.js
index de1ca025..56b7737d 100644
--- a/src/common.js
+++ b/src/common.js
@@ -63,9 +63,10 @@ function setup(env) {
 	* @api public
 	*/
 	function createDebug(namespace) {
-		let prevTime, value = createDebug.instances[namespace];
+		let prevTime;
+		const value = createDebug.instances[namespace];
 
-		if (!!value) {
+		if (value !== undefined) {
 			return value;
 		}
 
@@ -138,7 +139,7 @@ function setup(env) {
 	}
 
 	function destroy() {
-		if (createDebug.instances.hasOwnProperty(this.namespace)) {
+		if (createDebug.instances[this.namespace] !== undefined) {
 			delete createDebug.instances[this.namespace];
 			return true;
 		}