// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package testbed

import (
	"io/ioutil"
	"os"
	"testing"
)

// TestBed is an integration test helper that encapsulates setup and teardown. It ensures that tests
// are run in isolated directories. Always `defer teardown` to ensure teardown even if the
// current go-routine panics.
//
// Example:
//
//  func TestFoo(t *testing.T) {
//    tb := New(t)
//    tb.Setup()
//    defer tb.Teardown()
//    ... test code ...
//  }
//
type TestBed struct {
	t   *testing.T
	dir string
}

// New creates a new TestBed.
func New(t *testing.T) *TestBed {
	return &TestBed{t: t}
}

func (tb *TestBed) Setup() {
	if testing.Short() {
		tb.t.Skip("skipping integration tests when -test.short is set")
	}
	tmpdir, err := ioutil.TempDir("", "")
	if err != nil {
		tb.t.Fatal(err)
	}
	if err := os.Chdir(tmpdir); err != nil {
		tb.t.Fatal(err)
	}
	tb.dir = tmpdir
}

func (tb *TestBed) Teardown() {
	if err := os.RemoveAll(tb.dir); err != nil {
		tb.t.Fatal(err)
	}
}