gh-gocover – Share the coverage.html for a given pull request on GitHub. Requires git, gocover, gsutil, and gh.

gh-gocover

#! /bin/bash
set -euo pipefail

# Source: https://gist.github.com/maelvls/bd9b48ed236a4622e5c7794a04d73752

help() {
    cat <<EOF
Usage: gh gocover --pr <number> --bucket gs://bucket/path [flags]

Description:
  gh-gocover – Share the coverage.html for a given pull request on GitHub.
  Requires git, gocover, gsutil, and gh.

Flags:
  --pr         The pull-request number.
  --bucket     The bucket to upload the coverage report to. For example:
               gs://jetstack-mael-valais/gocover.

Optional flags:
  --repo       The repository to compare against. Defaults to the current
               repository.
  --branch     The ref to compare against. Defaults to origin/<default-branch>,
               <default-branch> being the default branch configured for that
               repository (e.g., main).
  --origin     The origin to fetch from. Defaults to origin.

  -h | --help  Show this message and exit.
EOF
}

# If gocover is not installed, install it.
if ! command -v gocover &>/dev/null; then
    echo "gocover is not installed. Installing..."
    go install github.com/Azure/gocover@latest
fi

origin=origin
pr=
repo=
bucket=
while [[ $# -gt 0 ]]; do
    case "$1" in
    --pr)
        if [[ -z "$2" ]]; then
            echo "Missing argument for $1"
            exit 1
        fi
        pr="$2"
        shift
        ;;
    --bucket)
        if [[ -z "$2" ]]; then
            echo "Missing argument for $1"
            exit 1
        fi
        if [[ "$2" != gs://* ]]; then
            echo "Bucket must be a gs:// URL"
            exit 1
        fi
        bucket="$2"
        shift
        ;;
    --repo)
        if [[ -z "$2" ]]; then
            echo "Missing argument for $1"
            exit 1
        fi
        repo="$2"
        shift
        ;;
    --origin)
        if [[ -z "$2" ]]; then
            echo "Missing argument for $1"
            exit 1
        fi
        origin="$2"
        shift
        ;;
    -h | --help)
        help
        exit 0
        ;;
    *)
        echo "Unknown flag: $1"
        help
        exit 1
        ;;
    esac
    shift
done

if [[ -z "$pr" ]]; then
    echo "Missing --pr flag"
    exit 1
fi
if [[ -z "$bucket" ]]; then
    echo "Missing --bucket flag"
    exit 1
fi

if [[ -z "${repo:-}" ]]; then
    repo=$(gh repo view --json name,owner --jq '"\(.owner.login)/\(.name)"')
fi
if [[ -z "${branch:-}" ]]; then
    branch=$(gh repo view --json defaultBranchRef --jq '.defaultBranchRef.name')
fi

git fetch --quiet "$origin" "$branch"
gh pr checkout "$pr"
go test ./... -coverprofile=/tmp/cover.out
gocover diff --repository-path="$PWD" --cover-profile=/tmp/cover.out --compare-branch="$branch" --outputdir=/tmp --coverage-baseline=0

gsutil cp /tmp/coverage.html "$bucket/${repo/\//-}-pr-$pr/coverage.html"
gsutil acl ch -u AllUsers:R "$bucket/${repo/\//-}-pr-$pr/coverage.html"

printf "URL: https://storage.googleapis.com/%s/%s-pr-%s/coverage.html\n" \
    "${bucket#gs://}" "${repo/\//-}" "$pr"