Fix focused note sometimes becoming invisible

gdn-app/src/components/CNote.vue

@@ -42,7 +42,7 @@ const hovering = ref(false);
 const mode = ref<"editing" | "creating">();
 
 const mayOpen = computed(() => children.value.length > 0);
-const open = computed(() => mayOpen.value && ui.openPaths.has(props.path));
+const open = computed(() => mayOpen.value && ui.isOpen(props.path));
 
 const focused = computed(() => ui.focusPath === props.path);
 const hover = computed(() => hovering.value && mode.value !== "editing");
@@ -52,11 +52,7 @@ const editing = computed(() => mode.value === "editing");
 
 // Ensure we're open if we need to be.
 watchEffect(() => {
-  if (props.forceOpen || creating.value) {
-    if (!ui.openPaths.has(props.path)) {
-      ui.openPaths.add(props.path);
-    }
-  }
+  if (props.forceOpen || creating.value) ui.setOpen(props.path, true);
 });
 
 // Ensure only one editor is ever open.
@@ -73,21 +69,13 @@ function focusOnThis() {
   ui.focusPath = props.path;
 }
 
-function toggleOpen() {
-  if (open.value) {
-    ui.openPaths.delete(props.path);
-  } else {
-    ui.openPaths.add(props.path);
-  }
-}
-
 function onClick() {
   if (!focused.value) {
     focusOnThis();
     return;
   }
 
-  toggleOpen();
+  ui.toggleOpen(props.path);
 }
 
 function onEditButtonClick() {
@@ -135,7 +123,7 @@ function onCreateEditorFinish(text: string) {
         <div
           class="rounded"
           :class="focused ? 'hover:bg-neutral-300' : 'hover:bg-neutral-200'"
-          @click.stop="toggleOpen()"
+          @click.stop="ui.toggleOpen(props.path)"
         >
           <RiArrowDownSLine v-if="open && props.forceOpen" size="16px" class="text-neutral-400" />
           <RiArrowDownSLine v-else-if="open" size="16px" />

gdn-app/src/stores/ui.ts

@@ -1,6 +1,6 @@
 import { pathAncestors, pathLiesOn } from "@/util";
 import { defineStore } from "pinia";
-import { ref, watch, watchEffect } from "vue";
+import { ref, watchEffect } from "vue";
 
 export const useUiStore = defineStore("ui", () => {
   const anchorId = ref<string>();
@@ -15,18 +15,31 @@ export const useUiStore = defineStore("ui", () => {
     }
   });
 
-  // Ensure the focusPath is updated when a node that lies on it is folded.
-  watch(openPaths, (now, old) => {
-    for (const folded of old.difference(now)) {
-      if (pathLiesOn(folded, focusPath.value)) {
-        focusPath.value = folded;
-      }
+  function isOpen(path: string): boolean {
+    return openPaths.value.has(path);
+  }
+
+  function setOpen(path: string, open: boolean) {
+    // Move the focusPath if necessary
+    if (!open && isOpen(path) && pathLiesOn(path, focusPath.value)) {
+      focusPath.value = path;
     }
-  });
+
+    // Don't update openPaths unnecessarily.
+    // Just in case vue itself doesn't debounce Set operations.
+    if (open && !isOpen(path)) openPaths.value.add(path);
+    else if (!open && isOpen(path)) openPaths.value.delete(path);
+  }
+
+  function toggleOpen(path: string) {
+    setOpen(path, !isOpen(path));
+  }
 
   return {
     anchorId,
     focusPath,
-    openPaths,
+    isOpen,
+    setOpen,
+    toggleOpen,
   };
 });