From ff4ab50b1d1bd05872e8ad56efa36e4027262ee0 Mon Sep 17 00:00:00 2001
From: Peter McLean <peter.cd.mclean@gmail.com>
Date: Sat, 2 Aug 2025 11:40:27 -0400
Subject: [PATCH 1/2] Add clang-format workflow

---
 .github/workflows/clang_format.yaml        | 58 ++++++++++++++++++++++
 .github/workflows/cmake-multi-platform.yml |  2 +
 2 files changed, 60 insertions(+)
 create mode 100644 .github/workflows/clang_format.yaml

diff --git a/.github/workflows/clang_format.yaml b/.github/workflows/clang_format.yaml
new file mode 100644
index 00000000..11967d6b
--- /dev/null
+++ b/.github/workflows/clang_format.yaml
@@ -0,0 +1,58 @@
+name: Clang Format Check
+
+on:
+  push:
+    branches: [ "master" ]
+    paths-ignore:
+      - '**/*.md'
+      - '*.md'
+  pull_request:
+    branches: [ "master" ]
+    paths-ignore:
+      - '**/*.md'
+      - '*.md'
+
+jobs:
+  clang-format:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Install clang-format
+      shell: bash
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y clang-format-19
+
+    - name: Get list of source files
+      id: files
+      shell: bash
+      run: |
+        FILES=$(git ls-files '*.cpp' '*.c' '*.h' '*.hpp' '*.cxx' '*.hxx' '*.cc' '*.hh' | tr '\n' ' ')
+        echo "FILES=${FILES}" >> $GITHUB_OUTPUT
+
+    - name: Check formatting
+      shell: bash
+      run: |
+        FILES="${{ steps.files.outputs.FILES }}"
+
+        if [[ -z "${FILES}" ]]; then
+          echo "No source files to check."
+          exit 0
+        fi
+
+        clang-format-19 --dry-run --Werror ${FILES} 2>&1 | tee clang-format-report.txt || true
+
+        if [[ -s clang-format-report.txt ]]; then
+          echo "❌ Code formatting issues found. See clang-format-report.txt."
+          exit 1
+        fi
+
+    - name: Upload clang-format report
+      if: failure()
+      uses: actions/upload-artifact@v4
+      with:
+        name: clang-format-report
+        path: clang-format-report.txt
diff --git a/.github/workflows/cmake-multi-platform.yml b/.github/workflows/cmake-multi-platform.yml
index 66d25613..c452235a 100644
--- a/.github/workflows/cmake-multi-platform.yml
+++ b/.github/workflows/cmake-multi-platform.yml
@@ -6,10 +6,12 @@ on:
     branches: [ "master" ]
     paths-ignore:
       - '**/*.md'
+      - '*.md'
   pull_request:
     branches: [ "master" ]
     paths-ignore:
       - '**/*.md'
+      - '*.md'
 
 jobs:
   run-matrix:

From e19c4318070b15f35b6f07547a6fd2ff3562d9fe Mon Sep 17 00:00:00 2001
From: Peter McLean <peter.cd.mclean@gmail.com>
Date: Sat, 2 Aug 2025 20:13:49 -0400
Subject: [PATCH 2/2] Check clang-format of diff/patch instead of everything

---
 .github/workflows/clang_format.yaml | 41 ++++++++++++++++-------------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/.github/workflows/clang_format.yaml b/.github/workflows/clang_format.yaml
index 11967d6b..59c0c12b 100644
--- a/.github/workflows/clang_format.yaml
+++ b/.github/workflows/clang_format.yaml
@@ -19,6 +19,8 @@ jobs:
     steps:
     - name: Checkout code
       uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
 
     - name: Install clang-format
       shell: bash
@@ -26,33 +28,36 @@ jobs:
         sudo apt-get update
         sudo apt-get install -y clang-format-19
 
-    - name: Get list of source files
-      id: files
-      shell: bash
+    - name: Fetch base branch
+      if: github.event_name == 'pull_request'
       run: |
-        FILES=$(git ls-files '*.cpp' '*.c' '*.h' '*.hpp' '*.cxx' '*.hxx' '*.cc' '*.hh' | tr '\n' ' ')
-        echo "FILES=${FILES}" >> $GITHUB_OUTPUT
+        echo "Fetching base branch ${{ github.base_ref }}"
+        git fetch origin ${{ github.base_ref }}:${{ github.base_ref }}
 
-    - name: Check formatting
-      shell: bash
+    - name: Get Git Diff
+      id: diff
       run: |
-        FILES="${{ steps.files.outputs.FILES }}"
-
-        if [[ -z "${FILES}" ]]; then
-          echo "No source files to check."
-          exit 0
+        if [[ "${{ github.event_name }}" == "pull_request" ]]; then
+          echo "Getting diff for pull request"
+          git diff origin/${{ github.base_ref }}...HEAD > diff.patch
+        else
+          echo "Getting diff for commit"
+          git diff ${{ github.event.before }} ${{ github.event.after }} > diff.patch
         fi
 
-        clang-format-19 --dry-run --Werror ${FILES} 2>&1 | tee clang-format-report.txt || true
+    - name: Check formatting
+      shell: bash
+      run: |
+        cat diff.patch | clang-format-diff-19 -p 1 > diff_format.patch
 
-        if [[ -s clang-format-report.txt ]]; then
-          echo "❌ Code formatting issues found. See clang-format-report.txt."
+        if [ -s diff_format.patch ]; then
+          echo "❌ Code formatting issues found. See diff_format.patch."
           exit 1
         fi
 
-    - name: Upload clang-format report
+    - name: Upload clang-formatted diff
       if: failure()
       uses: actions/upload-artifact@v4
       with:
-        name: clang-format-report
-        path: clang-format-report.txt
+        name: clang-format-diff
+        path: diff_format.patch