niri: keep workspace focus in sync with niri (#3713)

quickshell/Services/NiriService.qml

@@ -501,6 +501,11 @@ Singleton {
 
         setWorkspaces(updatedWorkspaces);
 
+        if (!data.focused) {
+            updateCurrentOutputWorkspaces();
+            return;
+        }
+
         focusedWorkspaceId = data.id;
         focusedWorkspaceIndex = allWorkspaces.findIndex(w => w.id === data.id);
 

quickshell/tests/niri-workspace-focus.test.mjs

@@ -0,0 +1,39 @@
+import assert from "node:assert/strict";
+import { readFileSync } from "node:fs";
+import test from "node:test";
+import vm from "node:vm";
+
+const source = readFileSync(new URL("../Services/NiriService.qml", import.meta.url), "utf8");
+
+function fixture() {
+    const context = vm.createContext({ workspaces: {}, allWorkspaces: [] });
+    context.root = context;
+    for (const [, name, args, body] of source.matchAll(/^    function (\w+)\(([^)]*)\) \{([\s\S]*?)^    \}/gm)) {
+        if (["setWorkspaces", "handleWorkspacesChanged", "handleWorkspaceActivated", "updateCurrentOutputWorkspaces"].includes(name))
+            vm.runInContext(`function ${name}(${args}) {${body}}`, context);
+    }
+    context.handleWorkspacesChanged({ workspaces: [
+        { id: 1, idx: 1, output: "eDP-1", is_active: true, is_focused: true },
+        { id: 2, idx: 1, output: "DP-1", is_active: true, is_focused: false },
+        { id: 3, idx: 2, output: "DP-1", is_active: false, is_focused: false }
+    ] });
+    return context;
+}
+
+test("scrolling the other output preserves focus; focusing it then transfers focus", () => {
+    const state = fixture();
+    state.handleWorkspaceActivated({ id: 3, focused: false });
+    assert.equal(state.workspaces[2].is_active, false);
+    assert.equal(state.workspaces[3].is_active, true);
+    assert.equal(state.focusedWorkspaceId, 1);
+    assert.equal(state.allWorkspaces[state.focusedWorkspaceIndex].id, 1);
+    assert.equal(state.currentOutput, "eDP-1");
+    assert.deepEqual(Array.from(state.currentOutputWorkspaces, w => w.id), [1]);
+
+    state.handleWorkspaceActivated({ id: 3, focused: true });
+    assert.equal(state.focusedWorkspaceId, 3);
+    assert.equal(state.allWorkspaces[state.focusedWorkspaceIndex].id, 3);
+    assert.equal(state.currentOutput, "DP-1");
+    assert.deepEqual(Array.from(state.allWorkspaces.filter(w => w.is_focused), w => w.id), [3]);
+    assert.deepEqual(Array.from(state.currentOutputWorkspaces, w => w.id), [2, 3]);
+});