From 0df4e49f1430dab791788921cbbbde92817438bd Mon Sep 17 00:00:00 2001
From: Bao Nguyen <39545125+giaBaoJS@users.noreply.github.com>
Date: Fri, 11 Sep 2026 04:36:16 +0700
Subject: [PATCH] Fix indentation drift for indented code blocks in list items
 (#19990)

Co-authored-by: fisker <lionkay@gmail.com>
---
 changelog_unreleased/markdown/19647.md        |  4 +-
 src/language-markdown/print/list.js           |  8 ++++
 .../__snapshots__/format.test.js.snap         | 47 +++++++++++++++++++
 .../markdown/list/tab-width/format.test.js    |  1 +
 .../list/tab-width/indented-code-block.md     | 17 +++++++
 5 files changed, 74 insertions(+), 3 deletions(-)
 create mode 100644 tests/format/markdown/list/tab-width/__snapshots__/format.test.js.snap
 create mode 100644 tests/format/markdown/list/tab-width/format.test.js
 create mode 100644 tests/format/markdown/list/tab-width/indented-code-block.md

diff --git a/changelog_unreleased/markdown/19647.md b/changelog_unreleased/markdown/19647.md
index 11504e69a..813a730d5 100644
--- a/changelog_unreleased/markdown/19647.md
+++ b/changelog_unreleased/markdown/19647.md
@@ -1,6 +1,4 @@
-#### Prevent indentation drift in task-list code blocks (#19647 by @Austin1serb)
-
-Indented code blocks inside task-list items no longer gain four spaces on each formatting pass.
+#### Prevent indentation drift in list-item code blocks (#19647, #19990 by @Austin1serb, @giaBaoJS)
 
 <!-- prettier-ignore -->
 ```markdown
diff --git a/src/language-markdown/print/list.js b/src/language-markdown/print/list.js
index cc890304e..eb4c5c673 100644
--- a/src/language-markdown/print/list.js
+++ b/src/language-markdown/print/list.js
@@ -103,6 +103,10 @@ function printListItem(path, options, print, listPrefix) {
           return align(" ".repeat(prefix.length), print());
         }
 
+        if (node.type === "code" && node.isIndented) {
+          return print();
+        }
+
         const alignment = " ".repeat(
           clamp(options.tabWidth - listPrefix.length, 0, 3), // 4+ will cause indented code block
         );
@@ -208,6 +212,10 @@ function printListItemLegacy(path, options, print, listPrefix) {
           return align(" ".repeat(prefix.length), print());
         }
 
+        if (node.type === "code" && node.isIndented) {
+          return print();
+        }
+
         const alignment = " ".repeat(
           clamp(options.tabWidth - listPrefix.length, 0, 3), // 4+ will cause indented code block
         );
diff --git a/tests/format/markdown/list/tab-width/__snapshots__/format.test.js.snap b/tests/format/markdown/list/tab-width/__snapshots__/format.test.js.snap
new file mode 100644
index 000000000..4133c06cd
--- /dev/null
+++ b/tests/format/markdown/list/tab-width/__snapshots__/format.test.js.snap
@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
+
+exports[`indented-code-block.md - {"tabWidth":4} format 1`] = `
+====================================options=====================================
+parsers: ["markdown", "mdx"]
+tabWidth: 4
+                                                      printWidth: 80 (default) |
+=====================================input======================================
+- [x] task item
+
+      indented code
+
+- unordered item
+
+      indented code
+
+- outer item
+
+  - nested item
+
+        indented code
+
+- item with extra code indentation
+
+          indented code
+
+=====================================output=====================================
+- [x] task item
+
+      indented code
+
+- unordered item
+
+      indented code
+
+- outer item
+
+    - nested item
+
+          indented code
+
+- item with extra code indentation
+
+          indented code
+
+================================================================================
+`;
diff --git a/tests/format/markdown/list/tab-width/format.test.js b/tests/format/markdown/list/tab-width/format.test.js
new file mode 100644
index 000000000..f4e2cd407
--- /dev/null
+++ b/tests/format/markdown/list/tab-width/format.test.js
@@ -0,0 +1 @@
+runFormatTest(import.meta, ["markdown", "mdx"], { tabWidth: 4 });
diff --git a/tests/format/markdown/list/tab-width/indented-code-block.md b/tests/format/markdown/list/tab-width/indented-code-block.md
new file mode 100644
index 000000000..e2afadbff
--- /dev/null
+++ b/tests/format/markdown/list/tab-width/indented-code-block.md
@@ -0,0 +1,17 @@
+- [x] task item
+
+      indented code
+
+- unordered item
+
+      indented code
+
+- outer item
+
+  - nested item
+
+        indented code
+
+- item with extra code indentation
+
+          indented code