From ef3c33ea8a42e768223d855933ca097d4a9aa9ad Mon Sep 17 00:00:00 2001
From: Isiah Meadows <contact@isiahmeadows.com>
Date: Mon, 30 Sep 2019 16:08:52 -0400
Subject: [PATCH] Add `params:` to `m.route.Link`, fix docs

---
 api/router.js            |  3 ++-
 api/tests/test-router.js | 30 ++++++++++++++++++++++++++++++
 docs/change-log.md       |  1 +
 docs/route.md            |  8 +++++---
 4 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/api/router.js b/api/router.js
index 46e79998d..284558a14 100644
--- a/api/router.js
+++ b/api/router.js
@@ -218,7 +218,8 @@ module.exports = function($window, mountRedraw) {
 				child.attrs.onclick = null
 			} else {
 				onclick = child.attrs.onclick
-				href = child.attrs.href
+				// Easier to build it now to keep it isomorphic.
+				href = buildPathname(child.attrs.href, child.attrs.params)
 				child.attrs.href = route.prefix + href
 				child.attrs.onclick = function(e) {
 					var result
diff --git a/api/tests/test-router.js b/api/tests/test-router.js
index 1dd760efa..97bbc4eb6 100644
--- a/api/tests/test-router.js
+++ b/api/tests/test-router.js
@@ -541,6 +541,36 @@ o.spec("route", function() {
 					o(route.set.args[2]).equals(opts)
 				})
 
+				o("passes params on route.Link", function() {
+					var e = $window.document.createEvent("MouseEvents")
+
+					e.initEvent("click", true, true)
+					e.button = 0
+					$window.location.href = prefix + "/"
+
+					route(root, "/", {
+						"/" : {
+							view: lock(function() {
+								return m(route.Link, {
+									href: "/test",
+									params: {key: "value"},
+								})
+							})
+						},
+						"/test" : {
+							view : lock(function() {
+								return m("div")
+							})
+						}
+					})
+					route.set = o.spy(route.set)
+
+					root.firstChild.dispatchEvent(e)
+
+					o(route.set.callCount).equals(1)
+					o(route.set.args[0]).equals("/test?key=value")
+				})
+
 				o("route.Link can render without routes or dom access", function() {
 					$window = browserMock(env)
 					var render = coreRenderer($window)
diff --git a/docs/change-log.md b/docs/change-log.md
index d11d6ad83..ef8df85f8 100644
--- a/docs/change-log.md
+++ b/docs/change-log.md
@@ -24,6 +24,7 @@
     - This is unlikely to break people because if you were to do it with `m.render` directly before now, you'd corrupt Mithril's internal representation and internal errors could occur as a result. Now, it just warns you.
 - For a better debugging experience with `m.route` route resolvers, errors on `onmatch` in the default route are left unhandled and errors in `onmatch` in other routes are logged to the console before redirecting. ([#2536](https://github.com/MithrilJS/mithril.js/pull/2536) [@isiahmeadows](https://github.com/isiahmeadows))
 - Bug fix with `m.redraw` where if you removed a root that was previously visited in the current redraw pass, it would lose its place and skip the next root.
+- Add `params:` attribute to `m.route.Link`. ([#????](https://github.com/MithrilJS/mithril.js/pull/????) [@isiahmeadows](https://github.com/isiahmeadows))
 
 -->
 
diff --git a/docs/route.md b/docs/route.md
index 823ca82e2..352284bb1 100644
--- a/docs/route.md
+++ b/docs/route.md
@@ -142,6 +142,7 @@ m(m.route.Link, {
 	// first parameter to `m`.
 	selector: "span",
 	options: {replace: true},
+	params: {key: "value"},
 	href: "/test",
 	disabled: false,
 	class: "nav-link",
@@ -201,9 +202,10 @@ Do note that this doesn't also disable pointer events for you - you have to do t
 Argument              | Type                                 | Required | Description
 --------------------- | ------------------------------------ | -------- | ---
 `attributes.href`     | `Object`                             | Yes      | The target route to navigate to.
-`attributes.selector` | `String|Object|Function`             | No      | This sets the tag name to use. Must be a valid selector for [`m`](hyperscript.md) if given, defaults to `"a"`.
-`attributes.options`  | `Object`                             | No      | This sets the options passed to [`m.route.set`](#mrouteset).
-`attributes.disabled` | `Object`                             | No      | This sets the options passed to [`m.route.set`](#mrouteset).
+`attributes.selector` | `String|Object|Function`             | No       | This sets the tag name to use. Must be a valid selector for [`m`](hyperscript.md) if given, defaults to `"a"`.
+`attributes.options`  | `Object`                             | No       | This sets the options passed to [`m.route.set`](#mrouteset).
+`attributes.params`   | `Object`                             | No       | This sets the parameters passed to [`m.route.set`](#mrouteset).
+`attributes.disabled` | `Object`                             | No       | This disables the link, so clicking on it doesn't route anywhere.
 `attributes`          | `Object`                             | No       | Other attributes to apply to the returned vnode may be passed.
 `children`            | `Array<Vnode>|String|Number|Boolean` | No       | Child [vnodes](vnodes.md) for this link.
 **returns**           | `Vnode`                              |          | A [vnode](vnodes.md).