Added more tests for config context

tests/mithril-tests.js

@@ -936,6 +936,26 @@ function testMithril(mock) {
 		m.render(root, m("div", {config: function(elem, isInitialized, ctx) {success = ctx.data===1}}));
 		return success;
 	})
+
+	// more complex config context
+	test(function() {
+		var root = mock.document.createElement("div")
+
+		var idx = 0;
+		var success = true;
+		var statefulConfig = function(elem, isInitialized, ctx) {ctx.data=idx++}
+		var node = m("div", {config: statefulConfig});
+		m.render(root, [node, node]);
+
+		idx = 0;
+		var checkConfig = function(elem, isInitialized, ctx) {
+			success = success && (ctx.data === idx++)
+		}
+		node = m("div", {config: statefulConfig});
+		m.render(root, [node, node]);
+		return success;
+	})
+
 }
 
 //mocks