From 81d007c124929f7cc94533a3e471e8807832869e Mon Sep 17 00:00:00 2001
From: "Alex Razumov (from Dev Box)" <alrazu@microsoft.com>
Date: Mon, 18 May 2026 17:04:44 -0700
Subject: [PATCH] Add Check diff coverage

---
 .github/workflows/ci.yml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4e33055e8..63efc75d2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -461,6 +461,12 @@ jobs:
             --workspace \
             --lcov --output-path lcov.info
 
+      - name: Check diff coverage
+        if: github.event_name == 'pull_request'
+        run: |
+          pip install diff-cover
+          diff-cover lcov.info --compare-branch=origin/main --fail-under=90
+
       - name: Generate miri code coverage
         env:
           RUSTFLAGS: "--cfg=miri"