Cargo Version Check Action

A GitHub Action to check if the version in Cargo.toml has changed compared to a base branch or previous commit. Useful for triggering release workflows only when the version number is bumped.

Features

• Compares current Cargo.toml version against a base branch or previous commit
• Outputs boolean flag for conditional workflow steps
• Returns both current and previous versions
• Supports custom Cargo.toml paths (e.g., for workspaces)
• Works with pull requests and manual triggers
• Provides helpful notices and error messages

Usage

Basic Usage (Pull Request)

name: CI

on:
  pull_request:
    branches: [main]

jobs:
  check-version:
    runs-on: ubuntu-latest
    outputs:
      version-changed: ${{ steps.version-check.outputs.version-changed }}
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0  # Required for git history comparison

      - name: Check if version changed
        id: version-check
        uses: joaommartins/cargo-version-check-action@v1
        with:
          base-ref: ${{ github.base_ref }}

      - name: Show version info
        run: |
          echo "Version changed: ${{ steps.version-check.outputs.version-changed }}"
          echo "Current: ${{ steps.version-check.outputs.current-version }}"
          echo "Previous: ${{ steps.version-check.outputs.previous-version }}"

  build-if-version-changed:
    needs: check-version
    if: needs.check-version.outputs.version-changed == 'true'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Build release
        run: cargo build --release

Workspace with Custom Cargo.toml Path

- name: Check if version changed
  id: version-check
  uses: joaommartins/cargo-version-check-action@v1
  with:
    base-ref: main
    cargo-toml-path: 'crates/my-crate/Cargo.toml'

Compare Against Previous Commit

If you don't specify a base-ref, the action will compare against the previous commit (HEAD~1):

- name: Check if version changed
  id: version-check
  uses: joaommartins/cargo-version-check-action@v1
  # No base-ref specified - compares with previous commit

Inputs

Input	Description	Required	Default
base-ref	Base branch reference for comparison (e.g., main). If not provided, compares against previous commit.	No	''
cargo-toml-path	Path to Cargo.toml file relative to repository root	No	Cargo.toml

Outputs

Output	Description	Example
version-changed	Whether the version has changed (true or false)	true
current-version	Current version in Cargo.toml	0.2.0
previous-version	Previous version in Cargo.toml	0.1.0

Common Patterns

Conditional Release Builds

Only build release binaries/wheels when version changes:

jobs:
  check-version:
    runs-on: ubuntu-latest
    outputs:
      version-changed: ${{ steps.check.outputs.version-changed }}
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - id: check
        uses: joaommartins/cargo-version-check-action@v1
        with:
          base-ref: ${{ github.base_ref }}

  release-build:
    needs: check-version
    if: needs.check-version.outputs.version-changed == 'true'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: cargo build --release
      # ... upload artifacts, publish, etc.

Manual Workflow Dispatch

on:
  workflow_dispatch:
  pull_request:

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

      - uses: joaommartins/cargo-version-check-action@v1
        with:
          # For PRs, uses github.base_ref
          # For manual dispatch, compares with previous commit
          base-ref: ${{ github.base_ref }}

Requirements

• Your workflow must check out the repository with fetch-depth: 0 to access git history
• The action requires bash shell (available on all GitHub-hosted runners)

Error Handling

The action will fail with clear error messages if:

• Cargo.toml is not found at the specified path
• Version cannot be extracted from Cargo.toml

It will provide warnings if:

• The specified base ref doesn't exist (falls back to previous commit comparison)

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License - see LICENSE file for details

Author

Created by @joaommartins