#!/usr/bin/env bash
set -euo pipefail

repository_dir=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)
cd "$repository_dir"

# Use the installed toolchain unless the caller explicitly selects another.
# Toolchains and dependencies must already be available locally.
export GOTOOLCHAIN=${GOTOOLCHAIN:-local}
export GOPROXY=off
go version

go_files=()
while IFS= read -r -d '' go_file; do
  if [[ -f "$go_file" ]]; then
    go_files+=("$go_file")
  fi
done < <(git ls-files --cached --others --exclude-standard -z -- '*.go')
if ((${#go_files[@]})); then
  unformatted=$(gofmt -l -- "${go_files[@]}")
  if [[ -n "$unformatted" ]]; then
    printf 'gofmt required for:\n%s\n' "$unformatted" >&2
    exit 1
  fi
fi

git diff --check HEAD --
while IFS= read -r -d '' candidate_file; do
  # --no-index returns 1 for differing content even when whitespace is clean;
  # whitespace errors return 2. Preserve other failures as well.
  git diff --no-index --check -- /dev/null "$candidate_file" || {
    check_status=$?
    if ((check_status != 1)); then
      exit "$check_status"
    fi
  }
done < <(git ls-files --others --exclude-standard -z)

go test ./...
go vet ./...
go build ./...