fix: Emojis and embeds cannot be copied to plain text clipboard (#3561)

shared/editor/lib/textBetween.ts

@@ -0,0 +1,43 @@
+import { Node as ProseMirrorNode } from "prosemirror-model";
+import { PlainTextSerializer } from "../types";
+
+/**
+ * Returns the text content between two positions.
+ *
+ * @param doc The Prosemirror document to use
+ * @param from A start point
+ * @param to An end point
+ * @param plainTextSerializers A map of node names to PlainTextSerializers which convert a node to plain text
+ * @returns A string of plain text
+ */
+export default function textBetween(
+  doc: ProseMirrorNode,
+  from: number,
+  to: number,
+  plainTextSerializers: Record<string, PlainTextSerializer | undefined>
+): string {
+  const blockSeparator = "\n\n";
+  let text = "";
+  let separated = true;
+
+  doc.nodesBetween(from, to, (node, pos) => {
+    const toPlainText = plainTextSerializers[node.type.name];
+
+    if (toPlainText) {
+      if (node.isBlock && !separated) {
+        text += blockSeparator;
+        separated = true;
+      }
+
+      text += toPlainText(node);
+    } else if (node.isText) {
+      text += node.text?.slice(Math.max(from, pos) - pos, to - pos);
+      separated = false;
+    } else if (node.isBlock && !separated) {
+      text += blockSeparator;
+      separated = true;
+    }
+  });
+
+  return text;
+}