add deprecation notice for debug.destroy()

src/browser.js

@@ -9,6 +9,16 @@ exports.save = save;
 exports.load = load;
 exports.useColors = useColors;
 exports.storage = localstorage();
+exports.destroy = (() => {
+	let warned = false;
+
+	return () => {
+		if (!warned) {
+			warned = true;
+			console.warn('Instance method `debug.destroy()` is deprecated and no longer does anything. It will be removed in the next major version of `debug`.');
+		}
+	};
+})();
 
 /**
  * Colors.

src/common.js

@@ -12,6 +12,7 @@ function setup(env) {
 	createDebug.enable = enable;
 	createDebug.enabled = enabled;
 	createDebug.humanize = require('ms');
+	createDebug.destroy = destroy;
 
 	Object.keys(env).forEach(key => {
 		createDebug[key] = env[key];
@@ -114,6 +115,7 @@ function setup(env) {
 		debug.useColors = createDebug.useColors();
 		debug.color = createDebug.selectColor(namespace);
 		debug.extend = extend;
+		debug.destroy = createDebug.destroy; // XXX Temporary. Will be removed in the next major release.
 
 		Object.defineProperty(debug, 'enabled', {
 			enumerable: true,
@@ -243,6 +245,14 @@ function setup(env) {
 		return val;
 	}
 
+	/**
+	* XXX DO NOT USE. This is a temporary stub function.
+	* XXX It WILL be removed in the next major release.
+	*/
+	function destroy() {
+		console.warn('Instance method `debug.destroy()` is deprecated and no longer does anything. It will be removed in the next major version of `debug`.');
+	}
+
 	createDebug.enable(createDebug.load());
 
 	return createDebug;

src/node.js

@@ -15,6 +15,10 @@ exports.formatArgs = formatArgs;
 exports.save = save;
 exports.load = load;
 exports.useColors = useColors;
+exports.destroy = util.deprecate(
+	() => {},
+	'Instance method `debug.destroy()` is deprecated and no longer does anything. It will be removed in the next major version of `debug`.'
+);
 
 /**
  * Colors.