fix(api): window label null instead of actual value, closes #3295 (#3332)

Author: lucasfernog

.changes/fix-window-label-api.md

@@ -0,0 +1,5 @@
+---
+"api": patch
+---
+
+Fixes `window.label` property returning null instead of the actual label.

.changes/refactor-window-metadata.md

@@ -0,0 +1,5 @@
+---
+"tauri": "patch"
+---
+
+**Breaking change:** Move `__currentWindow` and `__windows` values from `window.__TAURI__` to `window.__TAURI_METADATA__`.

core/tauri/scripts/bundle.js

@@ -158,7 +158,7 @@
       handler: window.__TAURI__.transformCallback(function (event) {
         if (event.payload) {
           var windowLabel = event.payload.label
-          window.__TAURI__.__windows.push({
+          window.__TAURI_METADATA__.__windows.push({
             label: windowLabel
           })
         }

core/tauri/scripts/core.js

@@ -424,20 +424,20 @@ impl<R: Runtime> WindowManager<R> {
 
     webview_attributes = webview_attributes
       .initialization_script(&self.inner.invoke_initialization_script)
-      .initialization_script(&self.initialization_script(&ipc_init,&pattern_init,&plugin_init, is_init_global)?)
       .initialization_script(&format!(
         r#"
-          if (!window.__TAURI__) {{
-            Object.defineProperty(window, '__TAURI__', {{
-              value: {{}}
-            }})
-          }}
-          window.__TAURI__.__windows = {window_labels_array}.map(function (label) {{ return {{ label: label }} }});
-          window.__TAURI__.__currentWindow = {{ label: {current_window_label} }}
+          Object.defineProperty(window, '__TAURI_METADATA__', {{
+            value: {{
+              __windows: {window_labels_array}.map(function (label) {{ return {{ label: label }} }}),
+              __currentWindow: {{ label: {current_window_label} }}
+            }}
+          }})
         "#,
         window_labels_array = serde_json::to_string(pending_labels)?,
         current_window_label = serde_json::to_string(&label)?,
-      ));
+      ))
+      .initialization_script(&self.initialization_script(&ipc_init,&pattern_init,&plugin_init, is_init_global)?)
+      ;
 
     #[cfg(feature = "isolation")]
     if let Pattern::Isolation { schema, .. } = self.pattern() {
@@ -1164,7 +1164,7 @@ fn on_window_event<R: Runtime>(
       let label = window.label();
       for window in manager.inner.windows.lock().unwrap().values() {
         window.eval(&format!(
-          r#"window.__TAURI__.__windows = window.__TAURI__.__windows.filter(w => w.label !== "{}");"#,
+          r#"window.__TAURI_METADATA__.__windows = window.__TAURI_METADATA__.__windows.filter(w => w.label !== "{}");"#,
           label
         ))?;
       }

core/tauri/src/manager.rs

@@ -164,7 +164,7 @@ interface WindowDef {
 /** @ignore */
 declare global {
   interface Window {
-    __TAURI__: {
+    __TAURI_METADATA__: {
       __windows: WindowDef[]
       __currentWindow: WindowDef
     }
@@ -193,7 +193,7 @@ enum UserAttentionType {
  * @return The current WebviewWindow.
  */
 function getCurrent(): WebviewWindow {
-  return new WebviewWindow(window.__TAURI__.__currentWindow.label, {
+  return new WebviewWindow(window.__TAURI_METADATA__.__currentWindow.label, {
     // @ts-expect-error
     skip: true
   })
@@ -205,7 +205,7 @@ function getCurrent(): WebviewWindow {
  * @return The list of WebviewWindow.
  */
 function getAll(): WebviewWindow[] {
-  return window.__TAURI__.__windows.map(
+  return window.__TAURI_METADATA__.__windows.map(
     (w) =>
       new WebviewWindow(w.label, {
         // @ts-expect-error
@@ -228,12 +228,8 @@ class WebviewWindowHandle {
   /** Local event listeners. */
   listeners: { [key: string]: Array<EventCallback<any>> }
 
-  constructor(label: WindowLabel | null | undefined) {
-    try {
-      this.label = label ?? window.__TAURI__.__currentWindow.label
-    } catch {
-      this.label = ''
-    }
+  constructor(label: WindowLabel) {
+    this.label = label
     // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
     this.listeners = Object.create(null)
   }
@@ -1100,10 +1096,7 @@ class WebviewWindow extends WindowManager {
    * * @param label The webview window label. It must be alphanumeric.
    * @returns The WebviewWindow instance to communicate with the webview.
    */
-  constructor(
-    label: WindowLabel | null | undefined,
-    options: WindowOptions = {}
-  ) {
+  constructor(label: WindowLabel, options: WindowOptions = {}) {
     super(label)
     // @ts-expect-error
     if (!options?.skip) {
@@ -1140,10 +1133,13 @@ class WebviewWindow extends WindowManager {
 }
 
 /** The WebviewWindow for the current window. */
-const appWindow = new WebviewWindow(null, {
-  // @ts-expect-error
-  skip: true
-})
+const appWindow = new WebviewWindow(
+  window.__TAURI_METADATA__.__currentWindow.label,
+  {
+    // @ts-expect-error
+    skip: true
+  }
+)
 
 /** Configuration for the window to create. */
 interface WindowOptions {