From a7f9c1e4261d4279a4b38ba8ef903cc0e0707ca5 Mon Sep 17 00:00:00 2001
From: "David E. Wheeler" <david@justatheory.com>
Date: Wed, 26 Jun 2024 14:12:47 -0400
Subject: [PATCH v2] Add tests for jsonpath `.*` on arrays

There was no coverage for the path to unwrap an array before applying
`.*` to it, so add tests that explicitly test `.*` for both objects and
arrays, showing how no results are returned for an array of scalars, but
results are returned when the array contains an object. Also test the
behavior in strict mode with and without the silent parameter, and with
the `@?` operator.

Unrelated but potentially useful to future source readers: document
`GetJsonPathVar` and `CountJsonPathVars`.
---
 src/backend/utils/adt/jsonpath_exec.c        |  7 ++-
 src/test/regress/expected/jsonb_jsonpath.out | 50 ++++++++++++++++++++
 src/test/regress/sql/jsonb_jsonpath.sql      | 11 +++++
 3 files changed, 67 insertions(+), 1 deletion(-)

diff --git a/src/backend/utils/adt/jsonpath_exec.c b/src/backend/utils/adt/jsonpath_exec.c
index d79c929822..bf69f0d824 100644
--- a/src/backend/utils/adt/jsonpath_exec.c
+++ b/src/backend/utils/adt/jsonpath_exec.c
@@ -2978,7 +2978,8 @@ getJsonPathItem(JsonPathExecContext *cxt, JsonPathItem *item,
 }
 
 /*
- * Returns the computed value of a JSON path variable with given name.
+ * Definition of JsonPathGetVarCallback for when JsonPathExecContext.vars
+ * is specified as a List value.
  */
 static JsonbValue *
 GetJsonPathVar(void *cxt, char *varName, int varNameLen,
@@ -3025,6 +3026,10 @@ GetJsonPathVar(void *cxt, char *varName, int varNameLen,
 	return result;
 }
 
+/*
+ * Definition of JsonPathCountVarsCallback for when JsonPathExecContext.vars
+ * is specified as a List value.
+ */
 static int
 CountJsonPathVars(void *cxt)
 {
diff --git a/src/test/regress/expected/jsonb_jsonpath.out b/src/test/regress/expected/jsonb_jsonpath.out
index a6112e86fa..3dea937887 100644
--- a/src/test/regress/expected/jsonb_jsonpath.out
+++ b/src/test/regress/expected/jsonb_jsonpath.out
@@ -4394,3 +4394,53 @@ ORDER BY s1.num, s2.num;
  {"s": "B"}    | {"s": "B"}    | false | true  | true  | true  | false
 (144 rows)
 
+-- Test any key on arrays with and without unwrapping.
+select jsonb_path_query('{"a": [1,2,3], "b": [3,4,5]}', '$.*');
+ jsonb_path_query 
+------------------
+ [1, 2, 3]
+ [3, 4, 5]
+(2 rows)
+
+select jsonb_path_query('[1,2,3]', '$.*');
+ jsonb_path_query 
+------------------
+(0 rows)
+
+select jsonb_path_query('[1,2,3,{"b": [3,4,5]}]', 'lax $.*');
+ jsonb_path_query 
+------------------
+ [3, 4, 5]
+(1 row)
+
+select jsonb_path_query('[1,2,3,{"b": [3,4,5]}]', 'strict $.*');
+ERROR:  jsonpath wildcard member accessor can only be applied to an object
+select jsonb_path_query('[1,2,3,{"b": [3,4,5]}]', 'strict $.*', NULL, true);
+ jsonb_path_query 
+------------------
+(0 rows)
+
+select jsonb '{"a": [1,2,3], "b": [3,4,5]}' @? '$.*';
+ ?column? 
+----------
+ t
+(1 row)
+
+select jsonb '[1,2,3]' @? '$.*';
+ ?column? 
+----------
+ f
+(1 row)
+
+select jsonb '[1,2,3,{"b": [3,4,5]}]' @? 'lax $.*';
+ ?column? 
+----------
+ t
+(1 row)
+
+select jsonb '[1,2,3,{"b": [3,4,5]}]' @? 'strict $.*';
+ ?column? 
+----------
+ 
+(1 row)
+
diff --git a/src/test/regress/sql/jsonb_jsonpath.sql b/src/test/regress/sql/jsonb_jsonpath.sql
index 5e14f7759b..f60bccc654 100644
--- a/src/test/regress/sql/jsonb_jsonpath.sql
+++ b/src/test/regress/sql/jsonb_jsonpath.sql
@@ -1116,3 +1116,14 @@ SELECT
 	jsonb_path_query_first(s1.j, '$.s > $s', vars => s2.j) gt
 FROM str s1, str s2
 ORDER BY s1.num, s2.num;
+
+-- Test any key on arrays with and without unwrapping.
+select jsonb_path_query('{"a": [1,2,3], "b": [3,4,5]}', '$.*');
+select jsonb_path_query('[1,2,3]', '$.*');
+select jsonb_path_query('[1,2,3,{"b": [3,4,5]}]', 'lax $.*');
+select jsonb_path_query('[1,2,3,{"b": [3,4,5]}]', 'strict $.*');
+select jsonb_path_query('[1,2,3,{"b": [3,4,5]}]', 'strict $.*', NULL, true);
+select jsonb '{"a": [1,2,3], "b": [3,4,5]}' @? '$.*';
+select jsonb '[1,2,3]' @? '$.*';
+select jsonb '[1,2,3,{"b": [3,4,5]}]' @? 'lax $.*';
+select jsonb '[1,2,3,{"b": [3,4,5]}]' @? 'strict $.*';
-- 
2.45.2