From 3029e29850c717feeea8530595632f698c29b3b2 Mon Sep 17 00:00:00 2001
From: George Adams <georgeadams1995@gmail.com>
Date: Thu, 10 Oct 2024 12:36:11 +0100
Subject: [PATCH] add changed_file check

---
 .github/workflows/build_test_containers.yml | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/build_test_containers.yml b/.github/workflows/build_test_containers.yml
index b160110022..eb66ce3f47 100644
--- a/.github/workflows/build_test_containers.yml
+++ b/.github/workflows/build_test_containers.yml
@@ -35,14 +35,15 @@ jobs:
               id: get_changed_files
               run: |
                 if [ ${{ github.event_name }} == "push" ]; then
-                    changed_files=$(git diff --name-only ${{ github.event.before }} ${{ github.sha }} | grep ansible/docker/test/Dockerfile)
+                    changed_files=$(git diff --name-only HEAD~1 | grep -v ansible/docker/test/Dockerfile)
                 else
-                    changed_files=$(git diff --name-only ${{ github.event.pull_request.base.sha }} ${{ github.event.pull_request.head.sha }} | grep ansible/docker/test/Dockerfile)
+                    changed_files=$(git diff --name-only ${{ github.event.pull_request.base.sha }} ${{ github.event.pull_request.head.sha }} | grep -v ansible/docker/test/Dockerfile)
                 fi
                 echo "changed_files=$changed_files" >> "$GITHUB_ENV"
 
             # Generate matrix
             - name: Generate matrix
+              if: steps.get_changed_files.outputs.changed_files
               id: generate_matrix
               run: |
                 matrix=$(jq -n --arg files "${changed_files}" '{