diff -U3 /home/pavel/src/postgresql.master/src/test/regress/expected/jsonb.out /home/pavel/src/postgresql.master/src/test/regress/results/jsonb.out
--- /home/pavel/src/postgresql.master/src/test/regress/expected/jsonb.out	2020-02-13 09:27:34.138317670 +0100
+++ /home/pavel/src/postgresql.master/src/test/regress/results/jsonb.out	2020-02-13 09:39:47.948547183 +0100
@@ -4701,19 +4701,19 @@
 select ('123'::jsonb)['a'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('123'::jsonb)[0];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('123'::jsonb)[NULL];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"a": 1}'::jsonb)['a'];
@@ -4725,25 +4725,25 @@
 select ('{"a": 1}'::jsonb)[0];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"a": 1}'::jsonb)['not_exist'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"a": 1}'::jsonb)[NULL];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('[1, "2", null]'::jsonb)['a'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('[1, "2", null]'::jsonb)[0];
@@ -4761,7 +4761,7 @@
 select ('[1, "2", null]'::jsonb)['1.0'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('[1, "2", null]'::jsonb)[1.0];
@@ -4809,7 +4809,7 @@
 select ('[1, "2", null]'::jsonb)[3];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('[1, "2", null]'::jsonb)[-2];
@@ -4821,13 +4821,13 @@
 select ('[1, "2", null]'::jsonb)[1]['a'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('[1, "2", null]'::jsonb)[1][0];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"a": 1, "b": "c", "d": [1, 2, 3]}'::jsonb)['b'];
@@ -4851,7 +4851,7 @@
 select ('{"a": 1, "b": "c", "d": [1, 2, 3]}'::jsonb)['d']['a'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"a": {"a1": {"a2": "aaa"}}, "b": "bbb", "c": "ccc"}'::jsonb)['a']['a1'];
@@ -4869,7 +4869,7 @@
 select ('{"a": {"a1": {"a2": "aaa"}}, "b": "bbb", "c": "ccc"}'::jsonb)['a']['a1']['a2']['a3'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"a": ["a1", {"b1": ["aaa", "bbb", "ccc"]}], "b": "bb"}'::jsonb)['a'][1]['b1'];
@@ -4899,7 +4899,7 @@
 select ('{"1": "a", "1.0": "b", "1.2": "c"}'::jsonb)[1.1];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"1": "a", "1.0": "b", "1.2": "c"}'::jsonb)[1.2];
@@ -4923,7 +4923,7 @@
 select ('{"1": "a", "1.0": "b", "1.2": "c"}'::jsonb)['1.1'];
  jsonb 
 -------
- 
+ NULL
 (1 row)
 
 select ('{"1": "a", "1.0": "b", "1.2": "c"}'::jsonb)['1.2'];