fix: bug with force pushed commits

action.yml

@@ -190,6 +190,7 @@ runs:
         GITHUB_WORKSPACE: ${{ github.workspace }}
         GITHUB_PULL_REQUEST_BASE_SHA: ${{ github.event.pull_request.base.sha }}
         GITHUB_EVENT_BEFORE: ${{ github.event.before }}
+        GITHUB_EVENT_FORCED : ${{ github.event.forced }}
         # INPUT_<VARIABLE_NAME> is not available in Composite run steps
         # https://docs.github.com/en/actions/creating-actions/metadata-syntax-for-github-actions#example-specifying-inputs
         INPUT_SHA: ${{ steps.sha.outputs.sha }}

diff-sha.sh

@@ -62,10 +62,13 @@ if [[ -z $GITHUB_BASE_REF ]]; then
   CURRENT_BRANCH=$TARGET_BRANCH && exit_status=$? || exit_status=$?
 
   if [[ -z $INPUT_BASE_SHA ]]; then
-    PREVIOUS_SHA=$GITHUB_EVENT_BEFORE
+    PREVIOUS_SHA=""
+
+    if [[ "$GITHUB_EVENT_FORCED" != "true" ]]; then
+      PREVIOUS_SHA=$GITHUB_EVENT_BEFORE
+    fi
 
     if [[ -z "$PREVIOUS_SHA" || "$PREVIOUS_SHA" == "0000000000000000000000000000000000000000" ]]; then
-      echo "::debug::First commit detected"
       PREVIOUS_SHA=$(git rev-parse "$(git branch -r --sort=-committerdate | head -1 | xargs)")
     fi