util/CopyExact: Test copying from interfaces and nil

diff --git a/util/copy.go b/util/copy.go
index 793a99cd951c832922dabd474a83e3c9080dd977..fda4cffc39906c68bf0881a076d33ae8f73a3faf 100644 (file)
--- a/util/copy.go
+++ b/util/copy.go
@@ -17,6 +17,9 @@ func CopyExact(dest interface{}, src interface{}) {
        if sV.Kind() == reflect.String {
                sV = sV.Convert(reflect.SliceOf(dV.Type().Elem()))
        }
+       if !sV.IsValid() {
+               panic("invalid source, probably nil")
+       }
        if dV.Len() != sV.Len() {
                panic(fmt.Sprintf("dest len (%d) != src len (%d)", dV.Len(), sV.Len()))
        }

diff --git a/util/copy_test.go b/util/copy_test.go
index 284840a3ad3982f7b45e69639e483ca698f95406..18c9e2d6b80da87d3c7ea8b326ad649c443fea4b 100644 (file)
--- a/util/copy_test.go
+++ b/util/copy_test.go
@@ -2,6 +2,7 @@ package util
 
 import (
        "bytes"
+       "strings"
        "testing"
 )
 
@@ -51,11 +52,29 @@ func TestCopySrcString(t *testing.T) {
        if string(dest) != "lol" {
                t.FailNow()
        }
+       func() {
+               defer func() {
+                       r := recover()
+                       if r == nil {
+                               t.FailNow()
+                       }
+               }()
+               CopyExact(dest, "rofl")
+       }()
+       var arr [5]byte
+       CopyExact(&arr, interface{}("hello"))
+       if string(arr[:]) != "hello" {
+               t.FailNow()
+       }
+}
+
+func TestCopySrcNilInterface(t *testing.T) {
+       var arr [3]byte
        defer func() {
-               r := recover()
-               if r == nil {
+               r := recover().(string)
+               if !strings.Contains(r, "invalid source") {
                        t.FailNow()
                }
        }()
-       CopyExact(dest, "rofl")
+       CopyExact(&arr, nil)
 }