# Conventional Semantic Git Tag Increment

A GitHub Action that automatically increments semantic version tags based on conventional commit messages.

Doesn't assume that you are using any special packaging software, etc. It just relies on Git having tags and commit messages.

## Usage

### Basic workflow

```yaml
name: Auto-tag

on:
  push:
    branches: [main]

jobs:
  tag:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - uses: tbehrendt/conventional-semantic-git-tag-increment@v1
        id: tag
        with:
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: Create and push tag
        run: |
          git tag ${{ steps.tag.outputs.new-tag }}
          git push origin ${{ steps.tag.outputs.new-tag }}
```

### With custom last tag

```yaml
- uses: tbehrendt/conventional-semantic-git-tag-increment@v1
  with:
    last-tag: "v2.1.0"
    token: ${{ secrets.GITHUB_TOKEN }}
```

### With prerelease tags

```yaml
- uses: tbehrendt/conventional-semantic-git-tag-increment@v1
  with:
    prerelease: "true"
    token: ${{ secrets.GITHUB_TOKEN }}
```

## Examples

| Commit Message                      | Current Tag | New Tag  | Reason               |
| ----------------------------------- | ----------- | -------- | -------------------- |
| `feat: add user authentication`     | `v1.0.0`    | `v1.1.0` | New feature          |
| `fix: resolve login bug`            | `v1.1.0`    | `v1.1.1` | Bug fix              |
| `feat!: change API response format` | `v1.1.1`    | `v2.0.0` | Breaking change      |
| `docs: update README`               | `v2.0.0`    | `v2.0.1` | Documentation update |

### Prerelease Examples

| Commit Message                  | Current Tag | New Tag (prerelease) | Reason      |
| ------------------------------- | ----------- | -------------------- | ----------- |
| `feat: add user authentication` | `v1.0.0`    | `1.1.0-rc-abc123`    | New feature |
| `fix: resolve login bug`        | `v1.1.0`    | `1.1.1-rc-def456`    | Bug fix     |

## Inputs

- `last-tag` (optional): Starting tag to increment from. If not provided, uses the latest tag in the repository.
- `token` (required): GitHub token for repository access. Use `${{ github.token }}` for public repos or a PAT for private repos.
- `prerelease` (optional): Whether to create a prerelease tag with `-rc-<github.sha>` suffix. Defaults to `false`.
- `max-tags` (optional): Maximum number of tags to fetch when looking for the latest non-pre-release tag. Defaults to `50`.

## Outputs

- `new-tag`: The incremented semantic version tag (e.g., `1.2.3` or `1.2.3-rc-abc123` for prerelease)