From 2458085eed462c5481a168f31281cef9d9e486c1 Mon Sep 17 00:00:00 2001
From: Tom Moor <tom@getoutline.com>
Date: Wed, 5 Apr 2023 09:02:26 -0400
Subject: [PATCH] fix: Draft comment on text gets into a strange state when
 unfocused (#5153)

---
 server/utils/ProsemirrorHelper.test.ts | 184 +++++++++++++++++++++++++
 shared/utils/ProsemirrorHelper.ts      |  48 +++++--
 2 files changed, 219 insertions(+), 13 deletions(-)
 create mode 100644 server/utils/ProsemirrorHelper.test.ts

diff --git a/server/utils/ProsemirrorHelper.test.ts b/server/utils/ProsemirrorHelper.test.ts
new file mode 100644
index 000000000..0068d04de
--- /dev/null
+++ b/server/utils/ProsemirrorHelper.test.ts
@@ -0,0 +1,184 @@
+import { Node } from "prosemirror-model";
+import ProsemirrorHelper from "@shared/utils/ProsemirrorHelper";
+import { schema } from "@server/editor";
+
+// Note: The test is here rather than shared to access the schema
+describe("#ProsemirrorHelper", () => {
+  describe("#trim", () => {
+    it("Does not remove single paragraph", () => {
+      const doc = Node.fromJSON(schema, {
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "  ",
+              },
+            ],
+          },
+        ],
+      });
+
+      expect(ProsemirrorHelper.trim(doc).toJSON()).toEqual({
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "  ",
+              },
+            ],
+          },
+        ],
+      });
+    });
+
+    it("Removes empty first paragraph", () => {
+      const doc = Node.fromJSON(schema, {
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "  ",
+              },
+            ],
+          },
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "one",
+              },
+            ],
+          },
+        ],
+      });
+
+      expect(ProsemirrorHelper.trim(doc).toJSON()).toEqual({
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "one",
+              },
+            ],
+          },
+        ],
+      });
+    });
+
+    it("Removes empty last paragraph", () => {
+      const doc = Node.fromJSON(schema, {
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "nice",
+              },
+            ],
+          },
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "  ",
+              },
+            ],
+          },
+        ],
+      });
+
+      expect(ProsemirrorHelper.trim(doc).toJSON()).toEqual({
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "nice",
+              },
+            ],
+          },
+        ],
+      });
+    });
+
+    it("Removes multiple empty paragraphs", () => {
+      const doc = Node.fromJSON(schema, {
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+          },
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "   ",
+              },
+            ],
+          },
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "nice",
+              },
+            ],
+          },
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "  ",
+              },
+            ],
+          },
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: " ",
+              },
+            ],
+          },
+        ],
+      });
+
+      expect(ProsemirrorHelper.trim(doc).toJSON()).toEqual({
+        type: "doc",
+        content: [
+          {
+            type: "paragraph",
+            content: [
+              {
+                type: "text",
+                text: "nice",
+              },
+            ],
+          },
+        ],
+      });
+    });
+  });
+});
diff --git a/shared/utils/ProsemirrorHelper.ts b/shared/utils/ProsemirrorHelper.ts
index b288178f4..4b1069b11 100644
--- a/shared/utils/ProsemirrorHelper.ts
+++ b/shared/utils/ProsemirrorHelper.ts
@@ -49,20 +49,42 @@ export default class ProsemirrorHelper {
    * @returns True if the editor is empty
    */
   static trim(doc: Node) {
-    const first = doc.firstChild;
-    const last = doc.lastChild;
-    const firstIsEmpty =
-      first &&
-      ProsemirrorHelper.toPlainText(first, doc.type.schema).trim() === "";
-    const lastIsEmpty =
-      last &&
-      ProsemirrorHelper.toPlainText(last, doc.type.schema).trim() === "";
-    const firstIsLast = first === last;
+    const { schema } = doc.type;
+    let index = 0,
+      start = 0,
+      end = doc.nodeSize - 2,
+      isEmpty;
 
-    return doc.cut(
-      firstIsEmpty ? first.nodeSize : 0,
-      lastIsEmpty && !firstIsLast ? doc.nodeSize - last.nodeSize : undefined
-    );
+    if (doc.childCount <= 1) {
+      return doc;
+    }
+
+    isEmpty = true;
+    while (isEmpty) {
+      const node = doc.maybeChild(index++);
+      if (!node) {
+        break;
+      }
+      isEmpty = ProsemirrorHelper.toPlainText(node, schema).trim() === "";
+      if (isEmpty) {
+        start += node.nodeSize;
+      }
+    }
+
+    index = doc.childCount - 1;
+    isEmpty = true;
+    while (isEmpty) {
+      const node = doc.maybeChild(index--);
+      if (!node) {
+        break;
+      }
+      isEmpty = ProsemirrorHelper.toPlainText(node, schema).trim() === "";
+      if (isEmpty) {
+        end -= node.nodeSize;
+      }
+    }
+
+    return doc.cut(start, end);
   }
 
   /**