diff --git a/ci/test/03_test_script.sh b/ci/test/03_test_script.sh
index c2117d7e97a..d81bd0b9ea8 100755
--- a/ci/test/03_test_script.sh
+++ b/ci/test/03_test_script.sh
@@ -198,7 +198,7 @@ if [[ "${RUN_IWYU}" == true ]]; then
              -Xiwyu --check_also="*/primitives/*.h" \
              2>&1 | tee /tmp/iwyu_ci.out
     python3 "/include-what-you-use/fix_includes.py" --nosafe_headers < /tmp/iwyu_ci.out
-    git diff -U0 | ./contrib/devtools/clang-format-diff.py -binary="clang-format-${TIDY_LLVM_V}" -p1 -i -v
+    git diff -U1 | ./contrib/devtools/clang-format-diff.py -binary="clang-format-${TIDY_LLVM_V}" -p1 -i -v
   }
 
   run_iwyu "compile_commands_iwyu_errors.json"