diff options
| -rw-r--r-- | common/collections/append.go | 7 | ||||
| -rw-r--r-- | common/collections/append_test.go | 12 |
2 files changed, 19 insertions, 0 deletions
diff --git a/common/collections/append.go b/common/collections/append.go index fe8792fc4..91abc46d3 100644 --- a/common/collections/append.go +++ b/common/collections/append.go @@ -31,6 +31,13 @@ func Append(to any, from ...any) (any, error) { var tot reflect.Type if !toIsNil { + if tov.Kind() == reflect.Slice { + // Create a copy of tov, so we don't modify the original. + c := reflect.MakeSlice(tov.Type(), tov.Len(), tov.Len()+len(from)) + reflect.Copy(c, tov) + tov = c + } + if tov.Kind() != reflect.Slice { return nil, fmt.Errorf("expected a slice, got %T", to) } diff --git a/common/collections/append_test.go b/common/collections/append_test.go index f997e7a20..415eb2f25 100644 --- a/common/collections/append_test.go +++ b/common/collections/append_test.go @@ -129,3 +129,15 @@ func TestAppendToMultiDimensionalSlice(t *testing.T) { } } + +func TestAppendShouldMakeACopyOfTheInputSlice(t *testing.T) { + t.Parallel() + c := qt.New(t) + slice := make([]string, 0, 100) + slice = append(slice, "a", "b") + result, err := Append(slice, "c") + c.Assert(err, qt.IsNil) + slice[0] = "d" + c.Assert(result, qt.DeepEquals, []string{"a", "b", "c"}) + c.Assert(slice, qt.DeepEquals, []string{"d", "b"}) +} |