Add "disable-empty-commits" option

As discussed in 80.

Note: I'm very much not a TS/JS dev, so I hope I've gotten it right ;-)

Also wasn't sure how to add tests for this, but hopefully you don't mind guiding me on that ? Feel free to push to my branch.

Author: jrfnl

README.md

@@ -116,6 +116,11 @@ is specific to GitHub wikis.
   links. This helps ensure that the Markdown works in source control as well as
   the wiki. The default is true.
 
+- **`disable-empty-commits`:** By default, any triggering of this action will
+  result in a commit to the Wiki, even if that commit is empty.
+  If this option is true, a workflow run which would result in no changes
+  to the Wiki files, will no longer create an empty commit. The default is false.
+
 #### `strategy:` input
 
 There are some specific usecases where using `strategy: init` might be better

action.yml

@@ -71,6 +71,14 @@ inputs:
       default is true.
     required: true
     default: true
+  disable-empty-commits:
+    description: >-
+      By default, any triggering of this action will result in a commit to the
+      Wiki, even if that commit is empty. If this option is true, a workflow
+      run which would result in no changes to the Wiki files, will no longer
+      create an empty commit. The default is false.
+    required: false
+    default: false
 outputs:
   wiki_url:
     description: >-
@@ -94,3 +102,4 @@ runs:
         INPUT_IGNORE: ${{ inputs.ignore }}
         INPUT_DRY_RUN: ${{ inputs.dry-run }}
         INPUT_PREPROCESS: ${{ inputs.preprocess }}
+        INPUT_DISABLE_EMPTY_COMMITS: ${{ inputs.disable-empty-commits }}

cli.ts

@@ -92,7 +92,11 @@ if (core.getBooleanInput("preprocess")) {
 }
 
 await $`git add -Av`;
-await $`git commit --allow-empty -m ${core.getInput("commit_message")}`;
+if (core.getBooleanInput("disable_empty_commits")) {
+  await $`git commit -m ${core.getInput("commit_message")}`;
+} else {
+  await $`git commit --allow-empty -m ${core.getInput("commit_message")}`;
+}
 
 if (core.getBooleanInput("dry_run")) {
   await $`git show`;