From b5ac3e47acb9a3821245c92b5e50ed12e79845b3 Mon Sep 17 00:00:00 2001
From: Jieyou Xu <jieyouxu@outlook.com>
Date: Mon, 20 Jul 2026 21:12:18 +0800
Subject: [PATCH 1/4] Simplify toolchain bump commit message template

Was needlessly verbose.
---
 Subtree sync procedure.md | 27 +++++++++------------------
 1 file changed, 9 insertions(+), 18 deletions(-)

diff --git a/Subtree sync procedure.md b/Subtree sync procedure.md
index ae3586a1c3b..6f0b8271dbb 100644
--- a/Subtree sync procedure.md	
+++ b/Subtree sync procedure.md	
@@ -121,28 +121,19 @@ chore: bump rustfmt toolchain to nightly-$LATEST_NIGHTLY_DATE
 
 Bumping the toolchain version as part of a git subtree push.
 
-current toolchain (nightly-$CURRENT_NIGHTLY_DATE):
-   - $CURRENT_NIGHTLY_VERSION-nightly ($CURRENT_NIGHTLY_HASH $CURRENT_NIGHTLY_DATE)
+Before:
 
-latest toolchain (nightly-$LATEST_NIGHTLY_DATE):
-   - $LATEST_NIGHTLY_VERSION-nightly ($LATEST_NIGHTLY_HASH $LATEST_NIGHTLY_DATE)
+```
+$CURRENT_NIGHTLY_VERSION-nightly ($CURRENT_NIGHTLY_HASH $CURRENT_NIGHTLY_DATE)
 ```
 
-Substituting the placeholders with the right information.
+After:
 
-> [!TIP]
->
-> Example bump commit message:
->
-> ```text
-> chore: bump rustfmt toolchain to nightly-2025-10-07
->
-> Bumping the toolchain version as part of a git subtree push.
->
-> current toolchain (nightly-2025-04-02): - 1.88.0-nightly (e2014e876 2025-04-01)
->
-> latest toolchain (nightly-2025-10-07): - 1.92.0-nightly (f6aa851db 2025-10-07)
-> ```
+```
+$LATEST_NIGHTLY_VERSION-nightly ($LATEST_NIGHTLY_HASH $LATEST_NIGHTLY_DATE)
+```
+
+Substituting the placeholders with the right information.
 
 ### 5. Open a PR against `rustfmt`
 

From cffd02de9ed1f5899b6baac6c053b2f91e4ab50f Mon Sep 17 00:00:00 2001
From: Jieyou Xu <jieyouxu@outlook.com>
Date: Mon, 20 Jul 2026 21:14:06 +0800
Subject: [PATCH 2/4] Remove noisy PR description template and make warning
 concise

---
 Subtree sync procedure.md | 25 ++-----------------------
 1 file changed, 2 insertions(+), 23 deletions(-)

diff --git a/Subtree sync procedure.md b/Subtree sync procedure.md
index 6f0b8271dbb..6dd8ed1073c 100644
--- a/Subtree sync procedure.md	
+++ b/Subtree sync procedure.md	
@@ -148,29 +148,8 @@ For the PR:
 - Include a copy of the bump commit message in the PR description for quick reference. Feel free to
   include additional notes that might be helpful for the maintainers when reviewing.
 
-> [!TIP]
->
-> Example subtree-push PR title and description:
->
-> **PR title**: `subtree-push nightly-2025-10-07`
->
-> **PR description**:
->
-> ```text
-> Bumping the toolchain version as part of a git subtree push.
->
-> current toolchain (nightly-2025-04-02):
-> - 1.88.0-nightly (e2014e876 2025-04-01)
->
-> latest toolchain (nightly-2025-10-07):
-> - 1.92.0-nightly (f6aa851db 2025-10-07)
-> ```
-
-> [!WARNING]
->
-> Make sure to immediately follow-up with a subtree-pull direction, syncing `rustfmt` to
-> `rust-lang/rust`. We need the {subtree-push, subtree-pull} directions to be performed in
-> lock-step, to minimize any changes in between that makes the logistics more complex.
+**Make sure to minimize the time between the subtree-push direction and the subtree-pull direction
+to avoid unnecessary complications.**
 
 ## Subtree pull direction: syncing from `rustfmt` to `rust-lang/rust`
 

From 73c01acfd0da628e617a396c1e6b56705fde4546 Mon Sep 17 00:00:00 2001
From: Jieyou Xu <jieyouxu@outlook.com>
Date: Mon, 20 Jul 2026 21:15:41 +0800
Subject: [PATCH 3/4] Elaborate on {edition,style-edition} Diff-Check combos

Realized this while looking at older subtree-push PRs.
---
 Subtree sync procedure.md | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Subtree sync procedure.md b/Subtree sync procedure.md
index 6dd8ed1073c..3eca7ff5734 100644
--- a/Subtree sync procedure.md	
+++ b/Subtree sync procedure.md	
@@ -138,8 +138,12 @@ Substituting the placeholders with the right information.
 ### 5. Open a PR against `rustfmt`
 
 And wait for the sync PR to be merged. The `rustfmt` maintainers will run Diff Check against the PR
-to catch any unexpected formatting changes. Once Diff Check failures are investigated and are
-resolved, the PR can then be merged.
+to catch any unexpected formatting changes.
+
+- Maintainers should trigger Diff-Check for the combinations of Edition {2021, 2024} x Style
+  Edition {2021, 2024}.
+
+Once Diff Check failures are investigated and are resolved, the PR can then be merged.
 
 For the PR:
 

From 8c597c8b99403ba98ba0cb4bf899be095731bbbb Mon Sep 17 00:00:00 2001
From: Jieyou Xu <jieyouxu@outlook.com>
Date: Mon, 20 Jul 2026 21:19:04 +0800
Subject: [PATCH 4/4] Add note for CHANGELOG and version number bumps

(Where applicable)
---
 Subtree sync procedure.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Subtree sync procedure.md b/Subtree sync procedure.md
index 3eca7ff5734..444246117d4 100644
--- a/Subtree sync procedure.md	
+++ b/Subtree sync procedure.md	
@@ -155,6 +155,12 @@ For the PR:
 **Make sure to minimize the time between the subtree-push direction and the subtree-pull direction
 to avoid unnecessary complications.**
 
+### 5. (Where applicable) Update changelog and bump rustfmt version number
+
+Where applicable, we may need to update the CHANGELOG entries with merged PRs (both in `rustfmt`
+repository and also in the `rust-lang/rust` `rustfmt` subtree that was included in the subtree-push
+merge), and then bump rustfmt version number.
+
 ## Subtree pull direction: syncing from `rustfmt` to `rust-lang/rust`
 
 > [!WARNING]