fix maxParams bug (#2166)

tree.go

@@ -357,6 +357,10 @@ func (n *node) insertChild(numParams uint8, path string, fullPath string, handle
 				maxParams: 1,
 				fullPath:  fullPath,
 			}
+			// update maxParams of the parent node
+			if n.maxParams < 1 {
+				n.maxParams = 1
+			}
 			n.children = []*node{child}
 			n.indices = string(path[i])
 			n = child

tree_test.go

@@ -368,6 +368,13 @@ func TestTreeCatchAllConflictRoot(t *testing.T) {
 	testRoutes(t, routes)
 }
 
+func TestTreeCatchMaxParams(t *testing.T) {
+	tree := &node{}
+	var route = "/cmd/*filepath"
+	tree.addRoute(route, fakeHandler(route))
+	checkMaxParams(t, tree)
+}
+
 func TestTreeDoubleWildcard(t *testing.T) {
 	const panicMsg = "only one wildcard per path segment is allowed"