Permalink
Browse files

tpl/collections: Fix union when the first slice is empty

Fixes #3686
  • Loading branch information...
bep committed Jul 8, 2017
1 parent 7bcc1ce commit dbbc5c4810a04ac06fad7500d88cf5c3bfe0c7fd
Showing with 16 additions and 0 deletions.
  1. +9 −0 tpl/collections/collections.go
  2. +7 −0 tpl/collections/collections_test.go
@@ -494,6 +494,7 @@ type intersector struct {
}
func (i *intersector) appendIfNotSeen(v reflect.Value) {
vi := v.Interface()
if !i.seen[vi] {
i.r = reflect.Append(i.r, v)
@@ -565,6 +566,14 @@ func (ns *Namespace) Union(l1, l2 interface{}) (interface{}, error) {
}
}
if !l1vv.IsValid() {
// The first slice may be empty. Pick the first value of the second
// to use as a prototype.
if l2v.Len() > 0 {
l1vv = l2v.Index(0)
}
}
for j := 0; j < l2v.Len(); j++ {
l2vv := l2v.Index(j)
@@ -666,6 +666,13 @@ func TestUnion(t *testing.T) {
{pagesVals{p1v}, pagesVals{p3v, p3v}, pagesVals{p1v, p3v}, false},
{[]interface{}{p1, p4}, []interface{}{p4, p2, p2}, []interface{}{p1, p4, p2}, false},
{[]interface{}{p1v}, []interface{}{p3v, p3v}, []interface{}{p1v, p3v}, false},
// #3686
{[]interface{}{p1v}, []interface{}{}, []interface{}{p1v}, false},
{[]interface{}{}, []interface{}{p1v}, []interface{}{p1v}, false},
{pagesPtr{p1}, pagesPtr{}, pagesPtr{p1}, false},
{pagesVals{p1v}, pagesVals{}, pagesVals{p1v}, false},
{pagesPtr{}, pagesPtr{p1}, pagesPtr{p1}, false},
{pagesVals{}, pagesVals{p1v}, pagesVals{p1v}, false},
// errors
{"not array or slice", []string{"a"}, false, true},

0 comments on commit dbbc5c4

Please sign in to comment.