Feature: optionally allow popups to not close on pressing Esc (#5730)

* add test for disabled popup ESC key functionality

* add closeOnEscapeKey default option for popup

* add ESC key condition to prevent map.closePopup

* fix variable indentation

* revert unnecessary mapPopup variable back to map._popup

* add 4 spaces of indentation to variables

spec/suites/map/handler/Map.KeyboardSpec.js

@@ -148,4 +148,19 @@ describe("Map.Keyboard", function () {
 		});
 	});
 
+	describe("popup closing disabled", function () {
+		it("close of popup when pressing escape disabled via options", function () {
+
+			var popup = L.popup({closeOnEscapeKey: false}).setLatLng([0, 0]).setContent('Null Island');
+			map.openPopup(popup);
+
+			expect(popup.isOpen()).to.be(true);
+
+			happen.keydown(document,  {keyCode: 27});
+			happen.keyup(document,    {keyCode: 27});
+
+			expect(popup.isOpen()).to.be(true);
+		});
+	});
+
 });

src/layer/Popup.js

@@ -87,6 +87,11 @@ export var Popup = DivOverlay.extend({
 		// the popup closing when another popup is opened.
 		autoClose: true,
 
+		// @option closeOnEscapeKey: Boolean = true
+		// Set it to `false` if you want to override the default behavior of
+		// the ESC key for closing of the popup.
+		closeOnEscapeKey: true,
+
 		// @option closeOnClick: Boolean = *
 		// Set it if you want to override the default behavior of the popup closing when user clicks
 		// on the map. Defaults to the map's [`closePopupOnClick`](#map-closepopuponclick) option.

src/map/handler/Map.Keyboard.js

@@ -162,7 +162,7 @@ export var Keyboard = Handler.extend({
 		} else if (key in this._zoomKeys) {
 			map.setZoom(map.getZoom() + (e.shiftKey ? 3 : 1) * this._zoomKeys[key]);
 
-		} else if (key === 27 && map._popup) {
+		} else if (key === 27 && map._popup && map._popup.options.closeOnEscapeKey) {
 			map.closePopup();
 
 		} else {