Add COPY FROM default tests

Relevant PG commit:
postgres/postgres@9f8377f
Already supported in Citus, adding the same tests as in PG

src/test/regress/expected/pg16.out

@@ -127,6 +127,112 @@ HINT:  Consider specifying a name for the statistics
 CREATE STATISTICS (ndistinct, dependencies, mcv) on a, b from test_stats;
 ERROR:  cannot create statistics without a name on a Citus table
 HINT:  Consider specifying a name for the statistics
+--
+-- COPY FROM ... DEFAULT
+-- Already supported in Citus, adding all PG tests with a distributed table
+-- Relevant PG commit:
+-- https://github.com/postgres/postgres/commit/9f8377f
+CREATE TABLE copy_default (
+	id integer PRIMARY KEY,
+	text_value text NOT NULL DEFAULT 'test',
+	ts_value timestamp without time zone NOT NULL DEFAULT '2022-07-05'
+);
+SELECT create_distributed_table('copy_default', 'id');
+ create_distributed_table
+---------------------------------------------------------------------
+
+(1 row)
+
+-- if DEFAULT is not specified, then the marker will be regular data
+COPY copy_default FROM stdin;
+SELECT * FROM copy_default ORDER BY id;
+ id | text_value |         ts_value
+---------------------------------------------------------------------
+  1 | value      | Mon Jul 04 00:00:00 2022
+  2 | D          | Tue Jul 05 00:00:00 2022
+(2 rows)
+
+TRUNCATE copy_default;
+COPY copy_default FROM stdin WITH (format csv);
+SELECT * FROM copy_default ORDER BY id;
+ id | text_value |         ts_value
+---------------------------------------------------------------------
+  1 | value      | Mon Jul 04 00:00:00 2022
+  2 | \D         | Tue Jul 05 00:00:00 2022
+(2 rows)
+
+TRUNCATE copy_default;
+-- DEFAULT cannot be used in binary mode
+COPY copy_default FROM stdin WITH (format binary, default '\D');
+ERROR:  cannot specify DEFAULT in BINARY mode
+-- DEFAULT cannot be new line nor carriage return
+COPY copy_default FROM stdin WITH (default E'\n');
+ERROR:  COPY default representation cannot use newline or carriage return
+COPY copy_default FROM stdin WITH (default E'\r');
+ERROR:  COPY default representation cannot use newline or carriage return
+-- DELIMITER cannot appear in DEFAULT spec
+COPY copy_default FROM stdin WITH (delimiter ';', default 'test;test');
+ERROR:  COPY delimiter must not appear in the DEFAULT specification
+-- CSV quote cannot appear in DEFAULT spec
+COPY copy_default FROM stdin WITH (format csv, quote '"', default 'test"test');
+ERROR:  CSV quote character must not appear in the DEFAULT specification
+-- NULL and DEFAULT spec must be different
+COPY copy_default FROM stdin WITH (default '\N');
+ERROR:  NULL specification and DEFAULT specification cannot be the same
+-- cannot use DEFAULT marker in column that has no DEFAULT value
+COPY copy_default FROM stdin WITH (default '\D');
+ERROR:  unexpected default marker in COPY data
+DETAIL:  Column "id" has no default value.
+CONTEXT:  COPY copy_default, line 1: "\D	value	'2022-07-04'"
+COPY copy_default FROM stdin WITH (format csv, default '\D');
+ERROR:  unexpected default marker in COPY data
+DETAIL:  Column "id" has no default value.
+CONTEXT:  COPY copy_default, line 1: "\D,value,2022-07-04"
+-- The DEFAULT marker must be unquoted and unescaped or it's not recognized
+COPY copy_default FROM stdin WITH (default '\D');
+SELECT * FROM copy_default ORDER BY id;
+ id | text_value |         ts_value
+---------------------------------------------------------------------
+  1 | test       | Mon Jul 04 00:00:00 2022
+  2 | \D         | Mon Jul 04 00:00:00 2022
+  3 | "D"        | Mon Jul 04 00:00:00 2022
+(3 rows)
+
+TRUNCATE copy_default;
+COPY copy_default FROM stdin WITH (format csv, default '\D');
+SELECT * FROM copy_default ORDER BY id;
+ id | text_value |         ts_value
+---------------------------------------------------------------------
+  1 | test       | Mon Jul 04 00:00:00 2022
+  2 | \\D        | Mon Jul 04 00:00:00 2022
+  3 | \D         | Mon Jul 04 00:00:00 2022
+(3 rows)
+
+TRUNCATE copy_default;
+-- successful usage of DEFAULT option in COPY
+COPY copy_default FROM stdin WITH (default '\D');
+SELECT * FROM copy_default ORDER BY id;
+ id | text_value |         ts_value
+---------------------------------------------------------------------
+  1 | value      | Mon Jul 04 00:00:00 2022
+  2 | test       | Sun Jul 03 00:00:00 2022
+  3 | test       | Tue Jul 05 00:00:00 2022
+(3 rows)
+
+TRUNCATE copy_default;
+COPY copy_default FROM stdin WITH (format csv, default '\D');
+SELECT * FROM copy_default ORDER BY id;
+ id | text_value |         ts_value
+---------------------------------------------------------------------
+  1 | value      | Mon Jul 04 00:00:00 2022
+  2 | test       | Sun Jul 03 00:00:00 2022
+  3 | test       | Tue Jul 05 00:00:00 2022
+(3 rows)
+
+TRUNCATE copy_default;
+-- DEFAULT cannot be used in COPY TO
+COPY (select 1 as test) TO stdout WITH (default '\D');
+ERROR:  COPY DEFAULT only available using COPY FROM
 -- Tests for SQL/JSON: support the IS JSON predicate
 -- Relevant PG commit:
 -- https://github.com/postgres/postgres/commit/6ee30209

src/test/regress/sql/pg16.sql

@@ -76,6 +76,97 @@ CREATE STATISTICS (dependencies) ON a, b FROM test_stats;
 CREATE STATISTICS (ndistinct, dependencies) on a, b from test_stats;
 CREATE STATISTICS (ndistinct, dependencies, mcv) on a, b from test_stats;
 
+--
+-- COPY FROM ... DEFAULT
+-- Already supported in Citus, adding all PG tests with a distributed table
+-- Relevant PG commit:
+-- https://github.com/postgres/postgres/commit/9f8377f
+CREATE TABLE copy_default (
+	id integer PRIMARY KEY,
+	text_value text NOT NULL DEFAULT 'test',
+	ts_value timestamp without time zone NOT NULL DEFAULT '2022-07-05'
+);
+SELECT create_distributed_table('copy_default', 'id');
+
+-- if DEFAULT is not specified, then the marker will be regular data
+COPY copy_default FROM stdin;
+1	value	'2022-07-04'
+2	\D	'2022-07-05'
+\.
+SELECT * FROM copy_default ORDER BY id;
+TRUNCATE copy_default;
+
+COPY copy_default FROM stdin WITH (format csv);
+1,value,2022-07-04
+2,\D,2022-07-05
+\.
+SELECT * FROM copy_default ORDER BY id;
+TRUNCATE copy_default;
+
+-- DEFAULT cannot be used in binary mode
+COPY copy_default FROM stdin WITH (format binary, default '\D');
+
+-- DEFAULT cannot be new line nor carriage return
+COPY copy_default FROM stdin WITH (default E'\n');
+COPY copy_default FROM stdin WITH (default E'\r');
+
+-- DELIMITER cannot appear in DEFAULT spec
+COPY copy_default FROM stdin WITH (delimiter ';', default 'test;test');
+
+-- CSV quote cannot appear in DEFAULT spec
+COPY copy_default FROM stdin WITH (format csv, quote '"', default 'test"test');
+
+-- NULL and DEFAULT spec must be different
+COPY copy_default FROM stdin WITH (default '\N');
+
+-- cannot use DEFAULT marker in column that has no DEFAULT value
+COPY copy_default FROM stdin WITH (default '\D');
+\D	value	'2022-07-04'
+2	\D	'2022-07-05'
+\.
+
+COPY copy_default FROM stdin WITH (format csv, default '\D');
+\D,value,2022-07-04
+2,\D,2022-07-05
+\.
+
+-- The DEFAULT marker must be unquoted and unescaped or it's not recognized
+COPY copy_default FROM stdin WITH (default '\D');
+1	\D	'2022-07-04'
+2	\\D	'2022-07-04'
+3	"\D"	'2022-07-04'
+\.
+SELECT * FROM copy_default ORDER BY id;
+TRUNCATE copy_default;
+
+COPY copy_default FROM stdin WITH (format csv, default '\D');
+1,\D,2022-07-04
+2,\\D,2022-07-04
+3,"\D",2022-07-04
+\.
+SELECT * FROM copy_default ORDER BY id;
+TRUNCATE copy_default;
+
+-- successful usage of DEFAULT option in COPY
+COPY copy_default FROM stdin WITH (default '\D');
+1	value	'2022-07-04'
+2	\D	'2022-07-03'
+3	\D	\D
+\.
+SELECT * FROM copy_default ORDER BY id;
+TRUNCATE copy_default;
+
+COPY copy_default FROM stdin WITH (format csv, default '\D');
+1,value,2022-07-04
+2,\D,2022-07-03
+3,\D,\D
+\.
+SELECT * FROM copy_default ORDER BY id;
+TRUNCATE copy_default;
+
+-- DEFAULT cannot be used in COPY TO
+COPY (select 1 as test) TO stdout WITH (default '\D');
+
 -- Tests for SQL/JSON: support the IS JSON predicate
 -- Relevant PG commit:
 -- https://github.com/postgres/postgres/commit/6ee30209