Support LOAD * in FT.AGGREGATE (#147)

* Support LOAD * in FT.AGGREGATE

* document

* add point

redisearch/aggregate.go

@@ -201,9 +201,13 @@ func (a *AggregateQuery) Limit(offset int, num int) *AggregateQuery {
 	return a
 }
 
-//Load document fields from the document HASH objects (if they are not in the sortables)
+//Load document fields from the document HASH objects (if they are not in the sortables).
+//Empty array will load all properties.
 func (a *AggregateQuery) Load(Properties []string) *AggregateQuery {
 	nproperties := len(Properties)
+	if nproperties == 0 {
+		a.AggregatePlan = a.AggregatePlan.Add("LOAD", "*")
+	}
 	if nproperties > 0 {
 		a.AggregatePlan = a.AggregatePlan.Add("LOAD", nproperties)
 		for _, property := range Properties {

redisearch/aggregate_test.go

@@ -616,10 +616,10 @@ func TestAggregateQuery_Load(t *testing.T) {
 			args{[]string{"field1", "field2", "field3", "field4"}},
 			redis.Args{"*", "LOAD", 4, "@field1", "@field2", "@field3", "@field4"},
 		},
-		{"TestAggregateQuery_Load_Empty",
+		{"TestAggregateQuery_Load_All",
 			fields{nil, redis.Args{}, nil, 0, false, false, false, nil},
 			args{[]string{}},
-			redis.Args{"*"},
+			redis.Args{"*", "LOAD", "*"},
 		},
 	}
 	for _, tt := range tests {