yew-router: Dynamic basename.

Author: finnbear

packages/yew-router/src/lib.rs

@@ -88,6 +88,10 @@ pub mod history {
         AnyHistory, BrowserHistory, HashHistory, History, HistoryError, HistoryResult, Location,
         MemoryHistory,
     };
+
+    pub(crate) mod query {
+        pub(crate) use gloo::history::query::Raw;
+    }
 }
 
 pub mod prelude {

packages/yew-router/src/navigator.rs

@@ -159,7 +159,7 @@ impl Navigator {
     pub(crate) fn prefix_basename<'a>(&self, route_s: &'a str) -> Cow<'a, str> {
         match self.basename() {
             Some(base) => {
-                if route_s.is_empty() && route_s.is_empty() {
+                if base.is_empty() && route_s.is_empty() {
                     Cow::from("/")
                 } else {
                     Cow::from(format!("{base}{route_s}"))

packages/yew-router/src/router.rs

@@ -1,9 +1,11 @@
 //! Router Component.
+use std::borrow::Cow;
 use std::rc::Rc;
 
 use yew::prelude::*;
 use yew::virtual_dom::AttrValue;
 
+use crate::history::query::Raw;
 use crate::history::{AnyHistory, BrowserHistory, HashHistory, History, Location};
 use crate::navigator::Navigator;
 use crate::utils::{base_url, strip_slash_suffix};
@@ -72,16 +74,37 @@ fn base_router(props: &RouterProps) -> Html {
         basename,
     } = props.clone();
 
+    let basename = basename.map(|m| strip_slash_suffix(&m).to_string());
+    let navigator = Navigator::new(history.clone(), basename.clone());
+
+    let old_basename = use_state_eq(|| Option::<String>::None);
+    if basename != *old_basename {
+        // If `old_basename` is `Some`, path is probably prefixed with `old_basename`.
+        // If `old_basename` is `None`, path may or may not be prefixed with the new `basename`,
+        // depending on whether this is the first render.
+        let old_navigator = Navigator::new(
+            history.clone(),
+            old_basename.as_ref().or(basename.as_ref()).cloned(),
+        );
+        old_basename.set(basename.clone());
+        let location = history.location();
+        let stripped = old_navigator.strip_basename(Cow::from(location.path()));
+        let prefixed = navigator.prefix_basename(&stripped);
+
+        if prefixed != location.path() {
+            history
+                .replace_with_query(prefixed, Raw(location.query_str()))
+                .unwrap_or_else(|never| match never {});
+        }
+    }
+
+    let navi_ctx = NavigatorContext { navigator };
+
     let loc_ctx = use_reducer(|| LocationContext {
         location: history.location(),
         ctr: 0,
     });
 
-    let basename = basename.map(|m| strip_slash_suffix(&m).to_string());
-    let navi_ctx = NavigatorContext {
-        navigator: Navigator::new(history.clone(), basename),
-    };
-
     {
         let loc_ctx_dispatcher = loc_ctx.dispatcher();
 

packages/yew-router/tests/link.rs

@@ -89,12 +89,11 @@ fn root_for_browser_router() -> Html {
     }
 }
 
-#[test]
 async fn link_in_browser_router() {
     let div = gloo::utils::document().create_element("div").unwrap();
     let _ = div.set_attribute("id", "browser-router");
     let _ = gloo::utils::body().append_child(&div);
-    yew::Renderer::<RootForBrowserRouter>::with_root(div).render();
+    let handle = yew::Renderer::<RootForBrowserRouter>::with_root(div).render();
 
     sleep(Duration::ZERO).await;
 
@@ -113,26 +112,43 @@ async fn link_in_browser_router() {
         "/search?q=Rust&lang=en_US",
         link_href("#browser-router ul > li.search-q-lang > a")
     );
+
+    handle.destroy();
+}
+
+#[derive(PartialEq, Properties)]
+struct BasenameProps {
+    basename: Option<String>,
 }
 
 #[function_component(RootForBasename)]
-fn root_for_basename() -> Html {
+fn root_for_basename(props: &BasenameProps) -> Html {
     html! {
-        <BrowserRouter basename="/base/">
+        <BrowserRouter basename={props.basename.clone()}>
             <NavigationMenu />
         </BrowserRouter>
     }
 }
 
-#[test]
 async fn link_with_basename() {
     let div = gloo::utils::document().create_element("div").unwrap();
     let _ = div.set_attribute("id", "with-basename");
     let _ = gloo::utils::body().append_child(&div);
-    yew::Renderer::<RootForBasename>::with_root(div).render();
+    let mut handle = yew::Renderer::<RootForBasename>::with_root_and_props(
+        div,
+        BasenameProps {
+            basename: Some("/base/".to_owned()),
+        },
+    )
+    .render();
 
     sleep(Duration::ZERO).await;
 
+    assert_eq!(
+        "/base/",
+        gloo::utils::window().location().pathname().unwrap()
+    );
+
     assert_eq!("/base/posts", link_href("#with-basename ul > li.posts > a"));
     assert_eq!(
         "/base/posts?page=2",
@@ -151,6 +167,48 @@ async fn link_with_basename() {
         "/base/search?q=Rust&lang=en_US",
         link_href("#with-basename ul > li.search-q-lang > a")
     );
+
+    // Some(a) -> Some(b)
+    handle.update(BasenameProps {
+        basename: Some("/bayes/".to_owned()),
+    });
+
+    sleep(Duration::ZERO).await;
+
+    assert_eq!(
+        "/bayes/",
+        gloo::utils::window().location().pathname().unwrap()
+    );
+
+    assert_eq!(
+        "/bayes/posts",
+        link_href("#with-basename ul > li.posts > a")
+    );
+
+    // Some -> None
+    handle.update(BasenameProps { basename: None });
+
+    sleep(Duration::ZERO).await;
+
+    assert_eq!("/", gloo::utils::window().location().pathname().unwrap());
+
+    assert_eq!("/posts", link_href("#with-basename ul > li.posts > a"));
+
+    // None -> Some
+    handle.update(BasenameProps {
+        basename: Some("/bass/".to_string()),
+    });
+
+    sleep(Duration::ZERO).await;
+
+    assert_eq!(
+        "/bass/",
+        gloo::utils::window().location().pathname().unwrap()
+    );
+
+    assert_eq!("/bass/posts", link_href("#with-basename ul > li.posts > a"));
+
+    handle.destroy();
 }
 
 #[function_component(RootForHashRouter)]
@@ -162,12 +220,11 @@ fn root_for_hash_router() -> Html {
     }
 }
 
-#[test]
 async fn link_in_hash_router() {
     let div = gloo::utils::document().create_element("div").unwrap();
     let _ = div.set_attribute("id", "hash-router");
     let _ = gloo::utils::body().append_child(&div);
-    yew::Renderer::<RootForHashRouter>::with_root(div).render();
+    let handle = yew::Renderer::<RootForHashRouter>::with_root(div).render();
 
     sleep(Duration::ZERO).await;
 
@@ -186,4 +243,14 @@ async fn link_in_hash_router() {
         "#/search?q=Rust&lang=en_US",
         link_href("#hash-router ul > li.search-q-lang > a")
     );
+
+    handle.destroy();
+}
+
+// These cannot be run in concurrently because they all read/write the URL.
+#[test]
+async fn sequential_tests() {
+    link_in_hash_router().await;
+    link_in_browser_router().await;
+    link_with_basename().await;
 }