name: CI

# This setup assumes that you run the unit tests with code coverage in the same
# workflow that will also print the coverage report as comment to the pull request. 
# Therefore, you need to trigger this workflow when a pull request is (re)opened or
# when new code is pushed to the branch of the pull request. In addition, you also
# need to trigger this workflow when new code is pushed to the main branch because 
# we need to upload the code coverage results as artifact for the main branch as
# well since it will be the baseline code coverage.
# 
# We do not want to trigger the workflow for pushes to *any* branch because this
# would trigger our jobs twice on pull requests (once from "push" event and once
# from "pull_request->synchronize")
on:
  pull_request:
    types: [opened, reopened, synchronize]
  push:
    branches:
      - 'main'

jobs:
  unit_tests:
    name: "Unit tests"
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Setup Go
        uses: actions/setup-go@v4
        with:
          go-version: ^1.22

      # When you execute your unit tests, make sure to use the "-coverprofile" flag to write a 
      # coverage profile to a file. You will need the name of the file (e.g. "coverage.txt")
      # in the next step as well as the next job.
      - name: Test
        run: go test -cover -coverprofile=coverage.txt ./...

      - name: Archive code coverage results
        uses: actions/upload-artifact@v4
        with:
          name: code-coverage
          path: coverage.txt # Make sure to use the same file name you chose for the "-coverprofile" in the "Test" step

  code_coverage:
    name: "Code coverage report"
    if: github.event_name == 'pull_request' # Do not run when workflow is triggered by push to main branch
    runs-on: ubuntu-latest
    needs: unit_tests # Depends on the artifact uploaded by the "unit_tests" job
    permissions:
      contents:      read
      actions:       read  # to download code coverage results from "test" job
      pull-requests: write # write permission needed to comment on PR
    steps:
      - uses: fgrosse/[email protected] # Consider using a Git revision for maximum security
        with:
          coverage-artifact-name: "code-coverage" # can be omitted if you used this default value
          coverage-file-name: "coverage.txt" # can be omitted if you used this default value

inputs:
  version:
    description: 'The exact version tag of the go-coverage-report tool to use.'
    required: true
    default: "v1.2.0"

  sha256sum:
    description: 'Optional SHA256 checksum of the tarball when downloading the go-coverage-report binary.'
    required: false

  coverage-artifact-name:
    description: 'The name of the artifact containing the code coverage results.'
    required: true
    default: "code-coverage"

  coverage-file-name:
    description: 'The name of the file containing the code coverage results.'
    required: true
    default: "coverage.txt"

  root-package:
    description: |
      The Go import path of the tested repository to add as a prefix to all paths of the
      changed files. This is useful to map the changed files (e.g., ["foo/my_file.go"]
      to their coverage profile which uses the full package name to identify the files
      (e.g., "github.com/fgrosse/example/foo/my_file.go"). Note that currently, 
      packages with a different name than their directory are not supported.
    required: false
    default: "github.com/${{ github.repository }}"

  skip-comment:
    description: |
      Skip creating or updating the pull request comment. This may be useful when you want
      to generate the coverage report and modify it in your own scripts.
    required: false
    default: 'false'

  trim:
    description: Trim a prefix in the "Impacted Packages" column of the markdown report.
    required: false

  github-baseline-workflow-ref:
    description: |
      The ref of the GitHub actions Workflow that produces the baseline coverage.
      By default, the GitHub Actions Workflow ref is used
      (e.g. "octocat/hello-world/.github/workflows/my-workflow.yml@refs/heads/my_branch").
      You can aso just pass the name of the Workflow file directly (e.g. "my-workflow.yml").
    default: ${{ github.workflow_ref }}
    required: false