Misc test tweaks (mistifyio#82)

Just some minor reworks for readability.

Author: mmlb

.github/workflows/formatters.sh

@@ -18,6 +18,10 @@ if ! nixfmt shell.nix; then
 	failed=1
 fi
 
+if ! rufo Vagrantfile; then
+	failed=1
+fi
+
 if ! git diff | (! grep .); then
 	failed=1
 fi

.gitignore

@@ -1,4 +1,5 @@
 bin
+go-zfs.test
 .vagrant
 
 # added by lint-install

Vagrantfile

@@ -1,13 +1,12 @@
-
 VAGRANTFILE_API_VERSION = "2"
 
 Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
-    config.vm.box = "ubuntu/trusty64"
-	config.ssh.forward_agent = true
+  config.vm.box = "ubuntu/trusty64"
+  config.ssh.forward_agent = true
 
-	config.vm.synced_folder ".", "/home/vagrant/go/src/github.com/mistifyio/go-zfs", create: true
+  config.vm.synced_folder ".", "/home/vagrant/go/src/github.com/mistifyio/go-zfs", create: true
 
-    config.vm.provision "shell", inline: <<EOF
+  config.vm.provision "shell", inline: <<EOF
 cat << END > /etc/profile.d/go.sh
 export GOPATH=\\$HOME/go
 export PATH=\\$GOPATH/bin:/usr/local/go/bin:\\$PATH
@@ -30,5 +29,4 @@ Defaults env_keep += "GOPATH"
 END
 
 EOF
-
 end

shell.nix

@@ -19,6 +19,7 @@ mkShell {
     nodePackages.prettier
     python3Packages.pip
     python3Packages.setuptools
+    rufo
     shfmt
     vagrant
   ];

test_helpers_test.go

@@ -0,0 +1,100 @@
+package zfs_test
+
+import (
+	"fmt"
+	"io/ioutil"
+	"math"
+	"os"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"testing"
+	"time"
+
+	"github.com/mistifyio/go-zfs/v3"
+)
+
+func sleep(delay int) {
+	time.Sleep(time.Duration(delay) * time.Second)
+}
+
+func pow2(x int) int64 {
+	return int64(math.Pow(2, float64(x)))
+}
+
+// https://github.com/benbjohnson/testing
+// assert fails the test if the condition is false.
+func _assert(t *testing.T, condition bool, msg string, v ...interface{}) {
+	t.Helper()
+
+	if !condition {
+		_, file, line, _ := runtime.Caller(2)
+		t.Logf("\033[31m%s:%d: "+msg+"\033[39m\n\n", append([]interface{}{filepath.Base(file), line}, v...)...)
+		t.FailNow()
+	}
+}
+
+func assert(t *testing.T, condition bool, msg string, v ...interface{}) {
+	t.Helper()
+	_assert(t, condition, msg, v...)
+}
+
+// ok fails the test if an err is not nil.
+func ok(t *testing.T, err error) {
+	t.Helper()
+	_assert(t, err == nil, "unexpected error: %v", err)
+}
+
+// nok fails the test if an err is nil.
+func nok(t *testing.T, err error) {
+	t.Helper()
+	_assert(t, err != nil, "expected error, got nil")
+}
+
+// equals fails the test if exp is not equal to act.
+func equals(t *testing.T, exp, act interface{}) {
+	t.Helper()
+	_assert(t, reflect.DeepEqual(exp, act), "exp: %#v\n\ngot: %#v", exp, act)
+}
+
+type cleanUpFunc func()
+
+func (f cleanUpFunc) cleanUp() {
+	f()
+}
+
+// do something like Restorer in github.com/packethost/pkg/internal/testenv/clearer.go
+func setupZPool(t *testing.T) cleanUpFunc {
+	t.Helper()
+
+	d, err := ioutil.TempDir("/tmp/", "zfs-test-*")
+	ok(t, err)
+
+	var skipRemoveAll bool
+	defer func() {
+		if !skipRemoveAll {
+			t.Logf("cleaning up")
+			os.RemoveAll(d)
+		}
+	}()
+
+	tempfiles := make([]string, 3)
+	for i := range tempfiles {
+		f, err := ioutil.TempFile(d, fmt.Sprintf("loop%d", i))
+		ok(t, err)
+
+		ok(t, f.Truncate(pow2(30)))
+
+		f.Close()
+		tempfiles[i] = f.Name()
+	}
+
+	pool, err := zfs.CreateZpool("test", nil, tempfiles...)
+	ok(t, err)
+
+	skipRemoveAll = true
+	return func() {
+		ok(t, pool.Destroy())
+		os.RemoveAll(d)
+	}
+}