A different way to clear the subtype on VDBE registers when the value of the register is overwritten with new content. To fix [[f45ac567eaa9f93].

FossilOrigin-Name: 2e9fb1295cd31fc29c97444c3dec82fef68e939f

test/json103.test

@@ -60,6 +60,19 @@ do_execsql_test json103-220 {
    WHERE rowid<7 GROUP BY b ORDER BY b;
 } {0 {{"n3":3,"n6":6}} 1 {{"n1":1,"n4":4}} 2 {{"n2":2,"n5":5}}}
 
-
+# ticket https://www.sqlite.org/src/info/f45ac567eaa9f93c 2016-01-30
+# Invalid JSON generated by json_group_array() 
+#
+# The underlying problem is a failure to reset Mem.eSubtype
+#
+do_execsql_test json103-300 {
+  DROP TABLE IF EXISTS t1;
+  CREATE TABLE t1(x);
+  INSERT INTO t1 VALUES(1),('abc');
+  SELECT
+     json_group_array(x),
+     json_group_array(json_object('x',x))
+    FROM t1;
+} {{[1,"abc"]} {[{"x":1},{"x":"abc"}]}}
 
 finish_test