feat: support n commit messages and previous commit message resolving

README.md

@@ -62,8 +62,14 @@ Add a step like this to your workflow:
 
     # The message for the commit.
     # Default: 'Commit from GitHub Actions (name of the workflow)'
+    # You can also provide multiple messages as a YAML/JSON array to create multiple commits
     message: 'Your commit message'
 
+    # Template for commit message. Use 'reuse' to reuse the previous commit's message,
+    # or use '{original}' placeholder in your message to include the previous commit message
+    # Default: ''
+    message_template: 'reuse'
+
     # If this input is set, the action will push the commit to a new branch with this name.
     # Default: ''
     new_branch: custom-new-branch
@@ -257,10 +263,64 @@ You can also use the `committer_name` and `committer_email` inputs to make it ap
     committer_email: 41898282+github-actions[bot]@users.noreply.github.com
 ```
 
+### Multiple commits and reusing commit messages
+
+You can create multiple commits in a single action run by providing an array of commit messages:
+
+```yaml
+- uses: EndBug/add-and-commit@v9
+  with:
+    message: |
+      - First commit message
+      - Second commit message
+      - Third commit message
+```
+
+#### Reusing previous commit messages
+
+You can reuse the previous commit's message exactly using the `message_template` input:
+
+```yaml
+- uses: EndBug/add-and-commit@v9
+  with:
+    message_template: 'reuse'
+```
+
+#### Templating with previous commit messages
+
+Use the `{original}` placeholder in `message_template` to include the previous commit message with additional text:
+
+**Suffix the previous message** (useful for formatting commits):
+```yaml
+- uses: EndBug/add-and-commit@v9
+  with:
+    message_template: '{original}\n\nFormatted code with prettier'
+```
+
+**Prefix the previous message**:
+```yaml
+- uses: EndBug/add-and-commit@v9
+  with:
+    message_template: 'chore: {original}'
+```
+
+**Wrap the previous message**:
+```yaml
+- uses: EndBug/add-and-commit@v9
+  with:
+    message_template: 'build: {original}\n\nCo-authored-by: bot@example.com'
+```
+
+This is particularly useful for automated workflows that need to preserve the original commit message while adding context like:
+- Formatting/linting notifications
+- Build system updates
+- Automated fixes
+- Co-author attributions
+
 ### Array inputs
 
 Due to limitations in the GitHub action APIs, all inputs must be either strings or booleans.
-The action supports arrays in `add` and `remove`, but they have to be encoded as a string with a YAML flow sequence:
+The action supports arrays in `add`, `remove`, and now `message`, but they have to be encoded as a string with a YAML flow sequence:
 
 ```yaml
 - uses: EndBug/add-and-commit@v9
@@ -280,6 +340,14 @@ The action supports arrays in `add` and `remove`, but they have to be encoded as
 
 (Note the pipe character making it a multiline string.)
 
+The same applies to the `message` input when creating multiple commits:
+
+```yaml
+- uses: EndBug/add-and-commit@v9
+  with:
+    message: '["First commit", "Second commit"]'
+```
+
 ### Automated linting
 
 Do you want to lint your JavaScript files, located in the `src` folder, with ESLint, so that fixable changes are done without your intervention? You can use a workflow like this:

action.yml

@@ -34,7 +34,10 @@ inputs:
     required: false
     default: --tags --force
   message:
-    description: The message for the commit
+    description: The message for the commit (can be a string, array of strings for multiple commits)
+    required: false
+  message_template:
+    description: Template for commit message. Use 'reuse' to reuse the previous commit's message exactly, or use '{original}' as a placeholder to include the previous message (e.g., '{original}\n\nFormatted code' to suffix, or 'chore: {original}' to prefix)
     required: false
   new_branch:
     description: The name of the branch to create.

src/io.ts

@@ -12,6 +12,7 @@ export interface InputTypes {
   default_author: 'github_actor' | 'user_info' | 'github_actions';
   fetch: string;
   message: string;
+  message_template: string | undefined;
   new_branch: string | undefined;
   pathspec_error_handling: 'ignore' | 'exitImmediately' | 'exitAtEnd';
   pull: string | undefined;

src/main.ts

@@ -114,15 +114,86 @@ core.info(`Running in ${baseDir}`);
     } else core.info('> Not pulling from repo.');
 
     core.info('> Creating commit...');
-    await git
-      .commit(getInput('message'), matchGitArgs(getInput('commit') || ''))
-      .then(async data => {
-        log(undefined, data);
-        setOutput('committed', 'true');
-        setOutput('commit_long_sha', data.commit);
-        setOutput('commit_sha', data.commit.substring(0, 7));
-      })
-      .catch(err => core.setFailed(err));
+
+    // Get commit messages - support for arrays and message templates
+    let messages = parseInputArray(getInput('message'));
+    const messageTemplate = getInput('message_template');
+
+    // Handle message template (reuse previous commit)
+    if (messageTemplate) {
+      try {
+        const previousCommit = await git.log(['-1']);
+        const previousMessage = previousCommit.latest?.message || '';
+
+        if (messageTemplate === 'reuse') {
+          // Reuse the entire previous commit message
+          messages = [previousMessage];
+          core.info(`> Reusing previous commit message: "${previousMessage}"`);
+        } else if (messageTemplate.includes('{original}')) {
+          // Replace {original} placeholder with previous message in the template
+          const templatedMessage = messageTemplate.replace(/\{original\}/g, previousMessage);
+          messages = [templatedMessage];
+          core.info(`> Using message template: "${templatedMessage}"`);
+        }
+      } catch (err) {
+        core.warning(`Could not retrieve previous commit message: ${err}`);
+      }
+    }
+
+    // Create commits (one or multiple)
+    let commitFailed = false;
+    for (let i = 0; i < messages.length; i++) {
+      const message = messages[i];
+      const isLastCommit = i === messages.length - 1;
+
+      if (messages.length > 1) {
+        core.info(`> Creating commit ${i + 1}/${messages.length}: "${message}"`);
+      }
+
+      // Check for staged changes before attempting commit
+      const stagedChanges = (await git.diffSummary(['--cached'])).files.length;
+      const commitArgs = matchGitArgs(getInput('commit') || '');
+      const allowEmpty = commitArgs.includes('--allow-empty');
+
+      if (stagedChanges === 0 && !allowEmpty) {
+        const errorMsg = `Cannot create commit ${i + 1}/${messages.length}: No staged changes found. Either stage files using add/remove inputs or use '--allow-empty' in the commit input to create empty commits.`;
+        core.setFailed(errorMsg);
+        break;
+      }
+
+      core.debug(
+        `Commit ${i + 1}: ${stagedChanges} staged files, --allow-empty: ${allowEmpty}`,
+      );
+
+      await git
+        .commit(message, commitArgs)
+        .then(async data => {
+          log(undefined, data);
+
+          // Only set outputs for the last commit
+          if (isLastCommit) {
+            setOutput('committed', 'true');
+            setOutput('commit_long_sha', data.commit);
+            setOutput('commit_sha', data.commit.substring(0, 7));
+          }
+        })
+        .catch(err => {
+          core.setFailed(err);
+          commitFailed = true;
+        });
+
+      // Stop processing if commit failed
+      if (commitFailed) {
+        break;
+      }
+
+      // Re-stage files for subsequent commits if there are more to create
+      if (!isLastCommit) {
+        core.info('> Re-staging files for next commit...');
+        if (getInput('add')) await add(ignoreErrors);
+        if (getInput('remove')) await remove(ignoreErrors);
+      }
+    }
 
     if (getInput('tag')) {
       core.info('> Tagging commit...');