From 4ed13fadb63a2d729f1f99eb5512253bcedeb585 Mon Sep 17 00:00:00 2001
From: "paseo-bot[bot]" <266920839+paseo-bot[bot]@users.noreply.github.com>
Date: Mon, 5 Oct 2026 21:52:51 +0200
Subject: [PATCH] fix(app): keep list numbers when a copy crosses a code block
 nested in an item (#6158)

A selection starting after an item's marker demotes that item to a paragraph.
When the item holds a code block, Turndown's HTML re-parse splits the paragraph
into several siblings, and counting siblings numbered the next item too high
("4. Done." instead of "2. Done."). Each item now carries its number before
the re-parse.

Closes #6140

Co-authored-by: paseo-bot[bot] <266920839+paseo-bot[bot]@users.noreply.github.com>
---
 .../content.browser.test.ts                   | 26 +++++++++++++++++++
 .../assistant-selection-copy/content.web.ts   | 19 +++++++++++---
 2 files changed, 42 insertions(+), 3 deletions(-)

diff --git a/packages/app/src/assistant-selection-copy/content.browser.test.ts b/packages/app/src/assistant-selection-copy/content.browser.test.ts
index 00a64406ea..995927f106 100644
--- a/packages/app/src/assistant-selection-copy/content.browser.test.ts
+++ b/packages/app/src/assistant-selection-copy/content.browser.test.ts
@@ -320,6 +320,32 @@ describe("assistant selection copy ranges", () => {
     ).toBe("6. Second bullet text");
   });
 
+  it("keeps the next number when a drag crosses a code block nested in an item", () => {
+    const message = mountFixture();
+    const list = fixtureElement(message, '[data-paseo-markdown-tag="ul"]');
+    list.outerHTML = [
+      '<div data-paseo-markdown-tag="ol" data-paseo-markdown-list-start="1">',
+      '<div data-paseo-markdown-tag="li">',
+      '<div data-paseo-markdown-ignore="true" data-paseo-markdown-list-marker="true">1.</div>',
+      "<div><div><span>Install it:</span></div>",
+      '<div data-paseo-markdown-tag="pre" data-paseo-markdown-language="sh">',
+      '<div data-paseo-markdown-tag="code"><span>brew install foo</span></div>',
+      '<button data-paseo-markdown-ignore="true">Copy</button>',
+      "</div></div>",
+      "</div>",
+      '<div data-paseo-markdown-tag="li">',
+      '<div data-paseo-markdown-ignore="true" data-paseo-markdown-list-marker="true">2.</div>',
+      "<div><div><span>Done.</span></div></div>",
+      "</div>",
+      "</div>",
+    ].join("");
+
+    const content = copyAcross(message, "Install it:", "Done.");
+
+    expect(content?.plainText).toBe("Install it:\n\n```sh\nbrew install foo\n```\n\n2. Done.");
+    expect(content?.html).toContain("<div>2. Done.</div>");
+  });
+
   it("retains nested markers when a drag includes the complete outer item", () => {
     const message = mountFixture();
     const firstItem = fixtureElement(message, '[data-paseo-markdown-tag="li"]');
diff --git a/packages/app/src/assistant-selection-copy/content.web.ts b/packages/app/src/assistant-selection-copy/content.web.ts
index aa6e6cd91b..ac4643b2ff 100644
--- a/packages/app/src/assistant-selection-copy/content.web.ts
+++ b/packages/app/src/assistant-selection-copy/content.web.ts
@@ -53,9 +53,7 @@ turndown.addRule("compactListItem", {
     if (parent?.nodeName !== "OL") {
       return `${options.bulletListMarker} ${item}\n`;
     }
-    const start = Number(parent.getAttribute("start") ?? 1);
-    const index = Array.from(parent.children).indexOf(node);
-    return `${start + index}. ${item}\n`;
+    return `${node.getAttribute("value")}. ${item}\n`;
   },
 });
 
@@ -536,6 +534,7 @@ function restoreMarkdownElements(container: HTMLElement): void {
       if (start) {
         semanticElement.setAttribute("start", start);
       }
+      numberOrderedListItems(semanticElement, Number(start ?? 1));
     }
     if (tagName === "pre") {
       const language = element.getAttribute(MARKDOWN_COPY_LANGUAGE_ATTRIBUTE);
@@ -568,6 +567,20 @@ function restoreMarkdownElements(container: HTMLElement): void {
   }
 }
 
+/**
+ * Each item carries its number before Turndown re-parses the HTML. Until then every
+ * child of the list is one item, including a partly selected item demoted to a `p`.
+ * The parser splits a `p` that holds a code block into several siblings, so counting
+ * siblings afterwards numbers the next item too high.
+ */
+function numberOrderedListItems(list: Element, start: number): void {
+  Array.from(list.children).forEach((child, index) => {
+    if (child.tagName === "LI") {
+      child.setAttribute("value", String(start + index));
+    }
+  });
+}
+
 function unwrapIncompleteTables(container: HTMLElement): void {
   for (const table of container.querySelectorAll("table")) {
     if (hasUsableTableColumnContract(table)) {