Fix bogus optimization in JSONB containment tests.

When determining whether one JSONB object contains another, it's okay to
make a quick exit if the first object has fewer pairs than the second:
because we de-duplicate keys within objects, it is impossible that the
first object has all the keys the second does.  However, the code was
applying this rule to JSONB arrays as well, where it does *not* hold
because arrays can contain duplicate entries.  The test was really in
the wrong place anyway; we should do it within JsonbDeepContains, where
it can be applied to nested objects not only top-level ones.

Report and test cases by Alexander Korotkov; fix by Peter Geoghegan and
Tom Lane.

3 files changed, 79 insertions, 0 deletions

diff --git a/src/test/regress/expected/jsonb.out b/src/test/regress/expected/jsonb.out
index eb37da7168..9146f59435 100644
--- a/src/test/regress/expected/jsonb.out
+++ b/src/test/regress/expected/jsonb.out
@@ -707,6 +707,42 @@ SELECT '{"a":"b", "b":1, "c":null}'::jsonb @> '{"a":"b", "c":"q"}';
  f
 (1 row)
 
+SELECT '[1,2]'::jsonb @> '[1,2,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,1,2]'::jsonb @> '[1,2,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[[1,2]]'::jsonb @> '[[1,2,2]]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,2]'::jsonb <@ '[1,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,2]'::jsonb <@ '[1,1,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[[1,2,2]]'::jsonb <@ '[[1,2]]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
 SELECT jsonb_contained('{"a":"b"}', '{"a":"b", "b":1, "c":null}');
  jsonb_contained 
 -----------------
diff --git a/src/test/regress/expected/jsonb_1.out b/src/test/regress/expected/jsonb_1.out
index f3bfc7bcf5..83d61f8c7e 100644
--- a/src/test/regress/expected/jsonb_1.out
+++ b/src/test/regress/expected/jsonb_1.out
@@ -707,6 +707,42 @@ SELECT '{"a":"b", "b":1, "c":null}'::jsonb @> '{"a":"b", "c":"q"}';
  f
 (1 row)
 
+SELECT '[1,2]'::jsonb @> '[1,2,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,1,2]'::jsonb @> '[1,2,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[[1,2]]'::jsonb @> '[[1,2,2]]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,2]'::jsonb <@ '[1,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[1,2,2]'::jsonb <@ '[1,1,2]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '[[1,2,2]]'::jsonb <@ '[[1,2]]'::jsonb;
+ ?column? 
+----------
+ t
+(1 row)
+
 SELECT jsonb_contained('{"a":"b"}', '{"a":"b", "b":1, "c":null}');
  jsonb_contained 
 -----------------
diff --git a/src/test/regress/sql/jsonb.sql b/src/test/regress/sql/jsonb.sql
index ed266d5c88..f1ed021be2 100644
--- a/src/test/regress/sql/jsonb.sql
+++ b/src/test/regress/sql/jsonb.sql
@@ -156,6 +156,13 @@ SELECT '{"a":"b", "b":1, "c":null}'::jsonb @> '{"a":"c"}';
 SELECT '{"a":"b", "b":1, "c":null}'::jsonb @> '{"a":"b"}';
 SELECT '{"a":"b", "b":1, "c":null}'::jsonb @> '{"a":"b", "c":"q"}';
 
+SELECT '[1,2]'::jsonb @> '[1,2,2]'::jsonb;
+SELECT '[1,1,2]'::jsonb @> '[1,2,2]'::jsonb;
+SELECT '[[1,2]]'::jsonb @> '[[1,2,2]]'::jsonb;
+SELECT '[1,2,2]'::jsonb <@ '[1,2]'::jsonb;
+SELECT '[1,2,2]'::jsonb <@ '[1,1,2]'::jsonb;
+SELECT '[[1,2,2]]'::jsonb <@ '[[1,2]]'::jsonb;
+
 SELECT jsonb_contained('{"a":"b"}', '{"a":"b", "b":1, "c":null}');
 SELECT jsonb_contained('{"a":"b", "c":null}', '{"a":"b", "b":1, "c":null}');
 SELECT jsonb_contained('{"a":"b", "g":null}', '{"a":"b", "b":1, "c":null}');