# name: test/sql/function/string/test_left.test
# description: LEFT test
# group: [string]

statement ok
PRAGMA enable_verification

foreach FUN LEFT LEFT_GRAPHEME

# test LEFT on positive positions
query TTTTT
SELECT ${FUN}('abcd', 0), ${FUN}('abc', 1), ${FUN}('abc', 2), ${FUN}('abc', 3), ${FUN}('abc', 4)
----
(empty)	a	ab	abc	abc

query TTTTT
SELECT ${FUN}('🦆ab', 0), ${FUN}('🦆ab', 1), ${FUN}('🦆ab', 2), ${FUN}('🦆ab', 3), ${FUN}('🦆ab', 4)
----
(empty)	🦆	🦆a	🦆ab	🦆ab

# test LEFT on negative positions
query TTTTT
SELECT ${FUN}('abcd', 0), ${FUN}('abc', -1), ${FUN}('abc', -2), ${FUN}('abc', -3), ${FUN}('abc', -4)
----
(empty)	ab	a	(empty)	(empty)

query TTTTT
SELECT ${FUN}('🦆ab', 0), ${FUN}('🦆ab', -1), ${FUN}('🦆ab', -2), ${FUN}('🦆ab', -3), ${FUN}('🦆ab', -4)
----
(empty)	🦆a	🦆	(empty)	(empty)

# test LEFT on NULL values
query TTT
SELECT ${FUN}(NULL, 0), ${FUN}('abc', NULL), ${FUN}(NULL, NULL)
----
NULL	NULL	NULL

query TTT
SELECT ${FUN}(NULL, 0), ${FUN}('🦆ab', NULL), ${FUN}(NULL, NULL)
----
NULL	NULL	NULL

# test on tables
statement ok
DROP TABLE IF EXISTS strings

statement ok
CREATE TABLE strings(a STRING, b BIGINT)

statement ok
INSERT INTO STRINGS VALUES ('abcd', 0), ('abc', 1), ('abc', 2), ('abc', 3), ('abc', 4)

query T
SELECT ${FUN}(a, b) FROM strings
----
(empty)
a
ab
abc
abc

statement ok
DROP TABLE IF EXISTS strings

statement ok
CREATE TABLE strings(a STRING, b BIGINT)

statement ok
INSERT INTO STRINGS VALUES ('abcd', 0), ('abc', -1), ('abc', -2), ('abc', -3), ('abc', -4)

query T
SELECT ${FUN}(a, b) FROM strings
----
(empty)
ab
a
(empty)
(empty)

statement ok
DROP TABLE IF EXISTS strings

statement ok
CREATE TABLE strings(a STRING, b BIGINT)

statement ok
INSERT INTO STRINGS VALUES (NULL, 0), ('abc', NULL), (NULL, NULL)

query T
SELECT ${FUN}(a, b) FROM strings
----
NULL
NULL
NULL

endloop

# grapheme clusters
query TTTT
SELECT LEFT_GRAPHEME('🦆🤦S̈', 0), LEFT_GRAPHEME('🦆🤦S̈', 1), LEFT_GRAPHEME('🦆🤦S̈', 2), LEFT_GRAPHEME('🦆🤦S̈', 3)
----
(empty)	🦆	🦆🤦	🦆🤦S̈

query TTTT
SELECT LEFT_GRAPHEME('🦆🤦S̈', 0), LEFT_GRAPHEME('🦆🤦S̈', -1), LEFT_GRAPHEME('🦆🤦S̈', -2), LEFT_GRAPHEME('🦆🤦S̈', -3)
----
(empty)	🦆🤦	🦆	(empty)