feat: add isDeadOrDying

core/comments/rendered_workspace_comment.ts

@@ -39,7 +39,9 @@ export class RenderedWorkspaceComment extends WorkspaceComment {
     this.view.addOnCollapseListener(
       () => void super.setCollapsed(this.view.isCollapsed()),
     );
-    this.view.addDisposeListener(() => void this.dispose());
+    this.view.addDisposeListener(() => {
+      if (!this.isDeadOrDying()) this.dispose();
+    });
   }
 
   /** Sets the text of the comment. */
@@ -78,6 +80,7 @@ export class RenderedWorkspaceComment extends WorkspaceComment {
 
   /** Disposes of the view. */
   override dispose() {
+    this.disposing = true;
     if (!this.view.isDeadOrDying()) this.view.dispose();
     super.dispose();
   }

core/comments/workspace_comment.ts

@@ -35,7 +35,10 @@ export class WorkspaceComment {
   private location = new Coordinate(0, 0);
 
   /** Whether this comment has been disposed or not. */
-  private disposed = false;
+  protected disposed = false;
+
+  /** Whether this comment is being disposed or not. */
+  protected disposing = false;
 
   /**
    * Constructs the comment.
@@ -158,11 +161,20 @@ export class WorkspaceComment {
 
   /** Disposes of this comment. */
   dispose() {
+    this.disposing = true;
     this.disposed = true;
   }
 
   /** Returns whether the comment has been disposed or not. */
   isDisposed() {
     return this.disposed;
   }
+
+  /**
+   * Returns true if this comment view is currently being disposed or has
+   * already been disposed.
+   */
+  isDeadOrDying(): boolean {
+    return this.disposing || this.disposed;
+  }
 }