remove spaces around arguments before calling macro expansion

pkg/tsdb/postgres/macros.go

@@ -30,7 +30,11 @@ func (m *PostgresMacroEngine) Interpolate(query *tsdb.Query, timeRange *tsdb.Tim
 	var macroError error
 
 	sql = replaceAllStringSubmatchFunc(rExp, sql, func(groups []string) string {
-		res, err := m.evaluateMacro(groups[1], strings.Split(groups[2], ","))
+		args := strings.Split(groups[2], ",")
+		for i, arg := range args {
+			args[i] = strings.Trim(arg, " ")
+		}
+		res, err := m.evaluateMacro(groups[1], args)
 		if err != nil && macroError == nil {
 			macroError = err
 			return "macro_error()"
@@ -95,7 +99,7 @@ func (m *PostgresMacroEngine) evaluateMacro(name string, args []string) (string,
 		if len(args) == 3 {
 			m.Query.Model.Set("fill", true)
 			m.Query.Model.Set("fillInterval", interval.Seconds())
-			if strings.Trim(args[2], " ") == "NULL" {
+			if args[2] == "NULL" {
 				m.Query.Model.Set("fillNull", true)
 			} else {
 				floatVal, err := strconv.ParseFloat(args[2], 64)

pkg/tsdb/postgres/macros_test.go

@@ -49,6 +49,14 @@ func TestMacroEngine(t *testing.T) {
 			So(sql, ShouldEqual, "GROUP BY (extract(epoch from time_column)/300)::bigint*300 AS time")
 		})
 
+		Convey("interpolate __timeGroup function with spaces between args", func() {
+
+			sql, err := engine.Interpolate(query, timeRange, "GROUP BY $__timeGroup(time_column , '5m')")
+			So(err, ShouldBeNil)
+
+			So(sql, ShouldEqual, "GROUP BY (extract(epoch from time_column)/300)::bigint*300 AS time")
+		})
+
 		Convey("interpolate __timeTo function", func() {
 			sql, err := engine.Interpolate(query, timeRange, "select $__timeTo(time_column)")
 			So(err, ShouldBeNil)