should be it

external/duckdb/test/sql/function/string/regex_extract.test

@@ -0,0 +1,112 @@
+# name: test/sql/function/string/regex_extract.test
+# description: regex extract test
+# group: [string]
+
+statement ok
+PRAGMA enable_verification
+
+query T
+SELECT regexp_extract('foobarbaz', 'b..')
+----
+bar
+
+query T
+SELECT regexp_extract('foobarbaz', 'B..')
+----
+(empty)
+
+# pass in regex options
+query T
+SELECT regexp_extract('foobarbaz', 'B..', 0, 'i')
+----
+bar
+
+query T
+SELECT regexp_extract('foobarbaz', 'b..', 1)
+----
+(empty)
+
+query T
+SELECT regexp_extract('foobarbaz', '(b..)(b..)')
+----
+barbaz
+
+query T
+SELECT regexp_extract('foobarbaz', '(b..)(b..)', 1)
+----
+bar
+
+query T
+SELECT regexp_extract('foobarbaz', '(b..)(b..)', 2)
+----
+baz
+
+statement error
+SELECT regexp_extract('foobarbaz', '(b..)(b..)', -1)
+----
+<REGEX>:.*Invalid Input Error: Group index must be.*
+
+statement error
+SELECT regexp_extract('foobarbaz', '(b..)(b..)', 42)
+----
+<REGEX>:.*Invalid Input Error: Group index must be.*
+
+statement ok
+CREATE TABLE test (s VARCHAR, p VARCHAR, i INT)
+
+statement ok
+INSERT INTO test VALUES
+    ('foobarbaz', 'b..', 0),
+    ('foobarbaz', 'b..', 1),
+    ('foobarbaz', '(b..)(b..)', 0),
+    ('foobarbaz', '(b..)(b..)', 1),
+    ('foobarbaz', '(b..)(b..)', 2)
+
+statement error
+SELECT regexp_extract(s, p, i) FROM test
+----
+<REGEX>:.*Invalid Input Error.*must be a constant.*
+
+query T
+SELECT regexp_extract(s, p, 0) FROM test
+----
+bar
+bar
+barbaz
+barbaz
+barbaz
+
+query T
+SELECT regexp_extract(s, 'b..', 0) FROM test
+----
+bar
+bar
+bar
+bar
+bar
+
+statement error
+SELECT regexp_extract(s, '(b..)(b..)', i) FROM test
+----
+<REGEX>:.*Invalid Input Error.*must be a constant.*
+
+# null values
+query T
+SELECT regexp_extract('foobarbaz', NULL, 0)
+----
+NULL
+
+query T
+SELECT regexp_extract('foobarbaz', 'b..', NULL)
+----
+(empty)
+
+query T
+SELECT regexp_extract(NULL, 'b..')
+----
+NULL
+
+statement error
+SELECT regexp_extract('foobarbaz', 'b..', '1')
+----
+<REGEX>:.*Binder Error.*Could not choose a best candidate.*