From e9e2a45caacfe76bc7817b4355bb522ad34381e3 Mon Sep 17 00:00:00 2001
From: Jared Jacobs <jaredjacobs@forwardnetworks.com>
Date: Wed, 29 Jun 2016 22:42:45 -0700
Subject: [PATCH] Fixing m.route() after a canceled navigation (#1126)

---
 mithril.js            | 17 ++++++++++++-----
 test/mithril.route.js |  2 ++
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/mithril.js b/mithril.js
index 28030022..4e972b89 100644
--- a/mithril.js
+++ b/mithril.js
@@ -1435,8 +1435,13 @@
 				removeRootElement(root, index)
 			}
 			return controllers[index]
-		} else if (component == null) {
-			removeRootElement(root, index)
+		} else {
+			if (component == null) {
+				removeRootElement(root, index)
+			}
+			if (previousRoute) {
+				currentRoute = previousRoute
+			}
 		}
 	}
 
@@ -1570,7 +1575,7 @@
 	var modes = {pathname: "", hash: "#", search: "?"}
 	var redirect = noop
 	var isDefaultRoute = false
-	var routeParams, currentRoute
+	var routeParams, currentRoute, previousRoute
 
 	m.route = function (root, arg1, arg2, vdom) { // eslint-disable-line
 		// m.route()
@@ -1623,7 +1628,7 @@
 		}
 		// m.route(route, params, shouldReplaceHistoryEntry)
 		if (isString(root)) {
-			var oldRoute = currentRoute
+			previousRoute = currentRoute
 			currentRoute = root
 
 			var args = arg1 || {}
@@ -1659,7 +1664,7 @@
 
 			var replaceHistory =
 				(arguments.length === 3 ? arg2 : arg1) === true ||
-				oldRoute === root
+				previousRoute === root
 
 			if (global.history.pushState) {
 				var method = replaceHistory ? "replaceState" : "pushState"
@@ -1681,6 +1686,8 @@
 				$location[m.route.mode] = currentRoute
 				redirect(modes[m.route.mode] + currentRoute)
 			}
+
+			previousRoute = null
 		}
 	}
 
diff --git a/test/mithril.route.js b/test/mithril.route.js
index 76ac5c09..11c529a6 100644
--- a/test/mithril.route.js
+++ b/test/mithril.route.js
@@ -127,6 +127,7 @@ describe("m.route()", function () {
 		route("/b")
 
 		expect(spy).to.not.have.been.called
+		expect(m.route()).to.equal("/a")
 	})
 
 	dit("skips route change if subcomponent ctrl.onunload calls preventDefault", function (root) { // eslint-disable-line
@@ -157,6 +158,7 @@ describe("m.route()", function () {
 		route("/b")
 
 		expect(spy).to.not.have.been.called
+		expect(m.route()).to.equal("/a")
 	})
 
 	dit("initializes a component's constructor on route change", function (root) { // eslint-disable-line