my computer is about to die!!!

helper/helper.go

@@ -0,0 +1,13 @@
+package helper
+
+import (
+	"errors"
+	"strings"
+)
+
+func JoinAsError(msg []string) error {
+	if len(msg) > 0 {
+		return errors.New(strings.Join(msg, "\n"))
+	}
+	return nil
+}

helper/helper_test.go

@@ -0,0 +1,21 @@
+package helper
+
+import (
+	"testing"
+)
+
+func TestJoinAsError(t *testing.T) {
+	var errs []string = nil
+	if JoinAsError(errs) != nil {
+		t.Error("expected no errors")
+	}
+	errs = make([]string, 0)
+	if JoinAsError(errs) != nil {
+		t.Error("expected no errors")
+	}
+
+	errs = []string{"a", "b"}
+	if JoinAsError(errs).Error() != "a\nb" {
+		t.Error("bad error")
+	}
+}

helper/test_helper.go

@@ -6,8 +6,10 @@ import (
 	"encoding/binary"
 	"encoding/json"
 	"io"
+	"io/ioutil"
 	"math/big"
 	"math/rand"
+	"os"
 )
 
 func B(x int64) *big.Int {
@@ -120,3 +122,19 @@ func GetRSAPrivateKey(size int) *rsa.PrivateKey {
 	return key
 
 }
+
+func GetTmpEmptyFile() *os.File {
+	if f, err := ioutil.TempFile("", ""); err != nil {
+		panic(err)
+	} else {
+		return f
+	}
+}
+
+func GetTmpEmptyDir() string {
+	if dirName, err := ioutil.TempDir("", ""); err != nil {
+		panic(err)
+	} else {
+		return dirName
+	}
+}