Support Required Any Kind of Slice

.travis.yml

@@ -1,6 +1,6 @@
 language: go
 go:
-  - 1.11.x
+  - 1.14.x
 go_import_path: github.com/teamwork/validate
 notifications:
   email: false

validate.go

@@ -239,31 +239,31 @@ func (v *Validator) Required(key string, value interface{}, message ...string) {
 		if len(val) == 0 {
 			v.Append(key, msg)
 		}
-	case []string:
-		if len(val) == 0 {
-			v.Append(key, msg)
+	default:
+		vv := reflect.ValueOf(value)
+		if vv.Kind() == reflect.Ptr {
+			if value == reflect.Zero(vv.Type()).Interface() {
+				v.Append(key, msg)
+			}
 			return
 		}
 
-		// Make sure there is at least one non-empty entry.
-		nonEmpty := false
-		for i := range val {
-			if val[i] != "" { // Consider " " to be non-empty on purpose.
-				nonEmpty = true
-				break
+		if vv.Kind() == reflect.Slice {
+			if vv.Len() == 0 {
+				v.Append(key, msg)
+				return
 			}
-		}
 
-		if !nonEmpty {
-			v.Append(key, msg)
-		}
-	default:
-		if vv := reflect.ValueOf(value); vv.Kind() == reflect.Ptr {
-			if value == reflect.Zero(vv.Type()).Interface() {
-				v.Append(key, msg)
+			for i := 0; i < vv.Len(); i++ {
+				if !vv.Index(i).IsZero() && !(vv.Kind() == reflect.Ptr && vv.Index(i).IsNil()) {
+					return
+				}
 			}
+
+			v.Append(key, msg)
 			return
 		}
+
 		panic(fmt.Sprintf("validate: not a supported type: %T", value))
 	}
 }

validate_test.go

@@ -64,6 +64,32 @@ func TestRequiredString(t *testing.T) {
 	}
 }
 
+func TestRequiredSlice(t *testing.T) {
+	tests := []struct {
+		a    interface{}
+		want bool
+	}{
+		{[]struct{}{}, true},
+		{[]struct{}{{}}, true},
+		{[]*struct{}{nil}, true},
+		{[]*struct{}{nil, {}}, false},
+		{[]string{}, true},
+		{[]string{""}, true},
+		{[]string{"text"}, false},
+	}
+
+	for i, tt := range tests {
+		name := fmt.Sprintf("%v", i)
+		t.Run(name, func(t *testing.T) {
+			v := New()
+			v.Required(name, tt.a)
+			if got := v.HasErrors(); got != tt.want {
+				t.Errorf("\ngot:  %#v\nwant: %#v\n", got, tt.want)
+			}
+		})
+	}
+}
+
 func TestRequiredPtr(t *testing.T) {
 	type customStruct struct {
 		String string