From 09937e39b039aff4884312fad1b0c85cb0d3f079 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Iv=C3=A1n=20S=C3=A1nchez=20Ortega?= <ivan@sanchezortega.es>
Date: Thu, 11 Aug 2016 09:10:46 +0200
Subject: [PATCH] Add a _leaflet_id to the map container to fix #4806 (#4810)

---
 spec/suites/map/MapSpec.js | 13 +++++++++++++
 src/map/Map.js             | 16 ++++++++++++----
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/spec/suites/map/MapSpec.js b/spec/suites/map/MapSpec.js
index ef8bb641..31d25ac0 100644
--- a/spec/suites/map/MapSpec.js
+++ b/spec/suites/map/MapSpec.js
@@ -69,6 +69,19 @@ describe("Map", function () {
 
 			expect(spy.called).to.not.be.ok();
 		});
+
+		it("throws error if container is reused by other instance", function () {
+			var container = document.createElement('div'),
+			    map = L.map(container),
+			    map2;
+
+			map.remove();
+			map2 = L.map(container);
+
+			expect(function () {
+				map.remove();
+			}).to.throwException();
+		});
 	});
 
 	describe('#getCenter', function () {
diff --git a/src/map/Map.js b/src/map/Map.js
index 8188c00a..e2e459d8 100644
--- a/src/map/Map.js
+++ b/src/map/Map.js
@@ -405,11 +405,19 @@ L.Map = L.Evented.extend({
 
 		this._initEvents(true);
 
+		if (this._containerId !== this._container._leaflet_id) {
+			throw new Error('Map container is being reused by another instance');
+		}
+
 		try {
 			// throws error in IE6-8
-			delete this._container._leaflet;
+			delete this._container._leaflet_id;
+			delete this._containerId;
 		} catch (e) {
-			this._container._leaflet = undefined;
+			/*eslint-disable */
+			this._container._leaflet_id = undefined;
+			/*eslint-enable */
+			this._containerId = undefined;
 		}
 
 		L.DomUtil.remove(this._mapPane);
@@ -712,12 +720,12 @@ L.Map = L.Evented.extend({
 
 		if (!container) {
 			throw new Error('Map container not found.');
-		} else if (container._leaflet) {
+		} else if (container._leaflet_id) {
 			throw new Error('Map container is already initialized.');
 		}
 
 		L.DomEvent.addListener(container, 'scroll', this._onScroll, this);
-		container._leaflet = true;
+		this._containerId = L.Util.stamp(container);
 	},
 
 	_initLayout: function () {