From 351e399362b087291f92c39ce5c37d679a5d7f3c Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Sun, 19 Jul 2026 10:20:39 +0800
Subject: [PATCH] YAML: Preserve order of anchor and tag (#19599)

---
 changelog_unreleased/yaml/19599.md            | 16 +++++++++++
 src/language-yaml/printer-yaml.js             | 23 +++++++++------
 .../spec/__snapshots__/format.test.js.snap    | 28 +++++++++----------
 .../__snapshots__/format.test.js.snap         | 14 +++++-----
 4 files changed, 51 insertions(+), 30 deletions(-)
 create mode 100644 changelog_unreleased/yaml/19599.md

diff --git a/changelog_unreleased/yaml/19599.md b/changelog_unreleased/yaml/19599.md
new file mode 100644
index 000000000..27cc3e5fc
--- /dev/null
+++ b/changelog_unreleased/yaml/19599.md
@@ -0,0 +1,16 @@
+#### Preserve order of anchor and tag (#19599 by @fisker)
+
+<!-- prettier-ignore -->
+```yaml
+# Input
+foo: &anchor1 !!str Value1
+bar: !!str &anchor2 Value2
+
+# Prettier stable
+foo: !!str &anchor1 Value1
+bar: !!str &anchor2 Value2
+
+# Prettier main
+foo: &anchor1 !!str Value1
+bar: !!str &anchor2 Value2
+```
diff --git a/src/language-yaml/printer-yaml.js b/src/language-yaml/printer-yaml.js
index 84da9b1ba..0e0d69b1e 100644
--- a/src/language-yaml/printer-yaml.js
+++ b/src/language-yaml/printer-yaml.js
@@ -52,15 +52,20 @@ function genericPrint(path, options, print) {
     parts.push([join(hardline, path.map(print, "leadingComments")), hardline]);
   }
 
-  const { tag, anchor } = node;
-  if (tag) {
-    parts.push(print("tag"));
+  const tagAndAnchor = ["tag", "anchor"].filter((property) => node[property]);
+  if (tagAndAnchor.length > 1) {
+    tagAndAnchor.sort(
+      (propertyA, propertyB) =>
+        locStart(node[propertyA]) - locStart(node[propertyB]),
+    );
   }
-  if (tag && anchor) {
-    parts.push(" ");
-  }
-  if (anchor) {
-    parts.push(print("anchor"));
+
+  for (const [index, property] of tagAndAnchor.entries()) {
+    if (index > 0) {
+      parts.push(" ");
+    }
+
+    parts.push(print(property));
   }
 
   /** @type {Doc} */
@@ -80,7 +85,7 @@ function genericPrint(path, options, print) {
     nextEmptyLine = printNextEmptyLine(path, options.originalText);
   }
 
-  if (tag || anchor) {
+  if (tagAndAnchor.length > 0) {
     if (isNode(node, ["sequence", "mapping"]) && !hasMiddleComments(node)) {
       parts.push(hardline);
     } else {
diff --git a/tests/format/yaml/spec/__snapshots__/format.test.js.snap b/tests/format/yaml/spec/__snapshots__/format.test.js.snap
index 2c9286ae5..9f537a26a 100644
--- a/tests/format/yaml/spec/__snapshots__/format.test.js.snap
+++ b/tests/format/yaml/spec/__snapshots__/format.test.js.snap
@@ -312,7 +312,7 @@ proseWrap: "always"
  - &d d
 
 =====================================output=====================================
-- !!str &a a
+- &a !!str a
 - !!int 2
 - !!int &c 4
 - &d d
@@ -332,7 +332,7 @@ useTabs: true
  - &d d
 
 =====================================output=====================================
-- !!str &a a
+- &a !!str a
 - !!int 2
 - !!int &c 4
 - &d d
@@ -2139,7 +2139,7 @@ key: &anchor
   a: b
 
 =====================================output=====================================
-key: !!map &anchor
+key: &anchor !!map
   a: b
 
 ================================================================================
@@ -2156,7 +2156,7 @@ key: &anchor
   a: b
 
 =====================================output=====================================
-key: !!map &anchor
+key: &anchor !!map
   a: b
 
 ================================================================================
@@ -7840,20 +7840,20 @@ value11
 
 =====================================output=====================================
 ---
-!!str &a1 scalar1
+&a1 !!str scalar1
 ---
 !!str &a2 scalar2
 ---
-!!str &a3 scalar3
+&a3 !!str scalar3
 ---
-!!map &a4
-!!str &a5 key5: value4
+&a4 !!map
+&a5 !!str key5: value4
 ---
 a6: 1
 &anchor6 b6: 2
 ---
 !!map
-!!str &a8 key8: value7
+&a8 !!str key8: value7
 ---
 !!map
 !!str &a10 key10: value9
@@ -7898,20 +7898,20 @@ value11
 
 =====================================output=====================================
 ---
-!!str &a1 scalar1
+&a1 !!str scalar1
 ---
 !!str &a2 scalar2
 ---
-!!str &a3 scalar3
+&a3 !!str scalar3
 ---
-!!map &a4
-!!str &a5 key5: value4
+&a4 !!map
+&a5 !!str key5: value4
 ---
 a6: 1
 &anchor6 b6: 2
 ---
 !!map
-!!str &a8 key8: value7
+&a8 !!str key8: value7
 ---
 !!map
 !!str &a10 key10: value9
diff --git a/tests/format/yaml/yaml-test-suite/__snapshots__/format.test.js.snap b/tests/format/yaml/yaml-test-suite/__snapshots__/format.test.js.snap
index dfd9bc8e8..cdd573166 100644
--- a/tests/format/yaml/yaml-test-suite/__snapshots__/format.test.js.snap
+++ b/tests/format/yaml/yaml-test-suite/__snapshots__/format.test.js.snap
@@ -1592,20 +1592,20 @@ value11
 
 =====================================output=====================================
 ---
-!!str &a1 scalar1
+&a1 !!str scalar1
 ---
 !!str &a2 scalar2
 ---
-!!str &a3 scalar3
+&a3 !!str scalar3
 ---
-!!map &a4
-!!str &a5 key5: value4
+&a4 !!map
+&a5 !!str key5: value4
 ---
 a6: 1
 &anchor6 b6: 2
 ---
 !!map
-!!str &a8 key8: value7
+&a8 !!str key8: value7
 ---
 !!map
 !!str &a10 key10: value9
@@ -2420,7 +2420,7 @@ key: &anchor
   a: b
 
 =====================================output=====================================
-key: !!map &anchor
+key: &anchor !!map
   a: b
 
 ================================================================================
@@ -3007,7 +3007,7 @@ parsers: ["yaml"]
  - &d d
 
 =====================================output=====================================
-- !!str &a a
+- &a !!str a
 - !!int 2
 - !!int &c 4
 - &d d