feat: new option keepFiles (#33)

README.md

@@ -199,6 +199,23 @@ For example:
     emptyCommits: false
 ```
 
+#### ⭐️ Keeping existing files
+
+By default, existing files in the publish branch are removed before adding the ones from publish dir. If you want the action to add new files but leave existing ones untouched, set the optional parameter `keepFiles` to `true`.
+
+For example:
+
+```yaml
+- name: deploy
+  uses: peaceiris/actions-gh-pages@v2.3.2
+  env:
+    ACTIONS_DEPLOY_KEY: ${{ secrets.ACTIONS_DEPLOY_KEY }}
+    PUBLISH_BRANCH: gh-pages
+    PUBLISH_DIR: ./public
+  with:
+    keepFiles: true
+```
+
 
 ## Tips and FAQ
 

action.yml

@@ -12,3 +12,7 @@ inputs:
     description: 'If empty commits should be made to the publication branch'
     required: false
     default: 'true'
+  keepFiles:
+    description: 'If existing files in the publish branch should be not removed before deploying'
+    required: false
+    default: 'false'

entrypoint.sh

@@ -61,7 +61,12 @@ remote_branch="${PUBLISH_BRANCH}"
 local_dir="${HOME}/$(tr -cd 'a-f0-9' < /dev/urandom | head -c 32)"
 if git clone --depth=1 --single-branch --branch "${remote_branch}" "${remote_repo}" "${local_dir}"; then
     cd "${local_dir}"
-    git rm -r --ignore-unmatch '*'
+
+    print_info "Keeping existing files: ${INPUT_KEEPFILES}"
+    if [[ ${INPUT_KEEPFILES} != "true" ]]; then
+        git rm -r --ignore-unmatch '*'
+    fi
+
     find "${GITHUB_WORKSPACE}/${PUBLISH_DIR}" -maxdepth 1 | \
         tail -n +2 | \
         xargs -I % cp -rf % "${local_dir}/"