tpl/collections: Allow first function to return an empty slice

Fixes #5235

diff --git a/docs/content/en/functions/first.md b/docs/content/en/functions/first.md
index 464dfa6717f0446a7c3b28910b819f5f73be4264..e4c0a848d44ee3f0c5e237141687d9610911c2b2 100644 (file)
--- a/docs/content/en/functions/first.md
+++ b/docs/content/en/functions/first.md
@@ -25,3 +25,5 @@ aliases: []
     {{ .Render "summary" }}
 {{ end }}
 ```
+
+*Note: Exclusive to `first`, LIMIT can be '0' to return an empty array.*

diff --git a/tpl/collections/collections.go b/tpl/collections/collections.go
index 4400a26b213e9f457be63f160bfbe3eaa8fde48a..4914216315cfbe3587e62be9679e4888a2549287 100644 (file)
--- a/tpl/collections/collections.go
+++ b/tpl/collections/collections.go
@@ -215,8 +215,8 @@ func (ns *Namespace) First(limit interface{}, seq interface{}) (interface{}, err
                return nil, err
        }
 
-       if limitv < 1 {
-               return nil, errors.New("can't return negative/empty count of items from sequence")
+       if limitv < 0 {
+               return nil, errors.New("can't return negative count of items from sequence")
        }
 
        seqv := reflect.ValueOf(seq)

diff --git a/tpl/collections/collections_test.go b/tpl/collections/collections_test.go
index c2d4cacbf199b43ff9c2a7aab5c9a057c5fd6f40..7b15151d2633b26ca057395a318f48314e20773f 100644 (file)
--- a/tpl/collections/collections_test.go
+++ b/tpl/collections/collections_test.go
@@ -256,6 +256,7 @@ func TestFirst(t *testing.T) {
                {int64(2), []int{100, 200, 300}, []int{100, 200}},
                {100, []int{100, 200}, []int{100, 200}},
                {"1", []int{100, 200, 300}, []int{100}},
+               {0, []string{"h", "u", "g", "o"}, []string{}},
                {int64(-1), []int{100, 200, 300}, false},
                {"noint", []int{100, 200, 300}, false},
                {1, nil, false},