function: correctly transform up explode nodes

engine_test.go

@@ -2481,6 +2481,16 @@ var generatorQueries = []struct {
 			{int64(3), "f", "third"},
 		},
 	},
+	{
+		`SELECT EXPLODE(SPLIT(c, "")) FROM t LIMIT 5`,
+		[]sql.Row{
+			{"f"},
+			{"i"},
+			{"r"},
+			{"s"},
+			{"t"},
+		},
+	},
 	{
 		`SELECT a, EXPLODE(b) AS x, c FROM t WHERE x = 'e'`,
 		[]sql.Row{

sql/expression/function/explode.go

@@ -86,7 +86,7 @@ func (e *Generate) String() string {
 
 // TransformUp implements the sql.Expression interface.
 func (e *Generate) TransformUp(f sql.TransformExprFunc) (sql.Expression, error) {
-	c, err := f(e.Child)
+	c, err := e.Child.TransformUp(f)
 	if err != nil {
 		return nil, err
 	}