Update slack vendor to master (#958)

1 files changed, 43 insertions, 0 deletions

diff --git a/vendor/github.com/nlopes/slack/interactions.go b/vendor/github.com/nlopes/slack/interactions.go
index 5433463d..de1ed370 100644
--- a/vendor/github.com/nlopes/slack/interactions.go
+++ b/vendor/github.com/nlopes/slack/interactions.go
@@ -1,6 +1,7 @@
 package slack
 
 import (
+	"bytes"
 	"encoding/json"
 )
 
@@ -53,6 +54,48 @@ type ActionCallbacks struct {
 	BlockActions      []*BlockAction
 }
 
+// MarshalJSON implements the Marshaller interface in order to combine both
+// action callback types back into a single array, like how the api responds.
+// This makes Marshaling and Unmarshaling an InteractionCallback symmetrical
+func (a ActionCallbacks) MarshalJSON() ([]byte, error) {
+	count := 0
+	length := len(a.AttachmentActions) + len(a.BlockActions)
+	buffer := bytes.NewBufferString("[")
+
+	f := func(obj interface{}) error {
+		js, err := json.Marshal(obj)
+		if err != nil {
+			return err
+		}
+		_, err = buffer.Write(js)
+		if err != nil {
+			return err
+		}
+
+		count++
+		if count < length {
+			_, err = buffer.WriteString(",")
+			return err
+		}
+		return nil
+	}
+
+	for _, act := range a.AttachmentActions {
+		err := f(act)
+		if err != nil {
+			return nil, err
+		}
+	}
+	for _, blk := range a.BlockActions {
+		err := f(blk)
+		if err != nil {
+			return nil, err
+		}
+	}
+	buffer.WriteString("]")
+	return buffer.Bytes(), nil
+}
+
 // UnmarshalJSON implements the Marshaller interface in order to delegate
 // marshalling and allow for proper type assertion when decoding the response
 func (a *ActionCallbacks) UnmarshalJSON(data []byte) error {