should be it

external/duckdb/test/sql/collate/icu_collation_propagation.test

@@ -0,0 +1,106 @@
+# name: test/sql/collate/icu_collation_propagation.test
+# description: Test collations with string functions
+# group: [collate]
+
+statement ok
+create table tbl (a varchar, b varchar);
+
+statement ok
+insert into tbl values ('ö', '>>>>>ö<<<<<'), ('o', '>>>>>o<<<<<'), ('p', '>>>>>p<<<<<');
+
+require icu
+
+# test propagation of collation through string functions
+query I
+select concat(a collate de, a) from tbl order by all;
+----
+oo
+öö
+pp
+
+query I
+select lower(a collate de) from tbl order by all;
+----
+o
+ö
+p
+
+query I
+select upper(a collate de) from tbl order by all;
+----
+O
+Ö
+P
+
+query I
+select trim(b collate de, '<>') from tbl order by all
+----
+o
+ö
+p
+
+query I
+select ltrim(b collate de, '<>') from tbl order by all
+----
+o<<<<<
+ö<<<<<
+p<<<<<
+
+query I
+select rtrim(b collate de, '<>') from tbl order by all
+----
+>>>>>o
+>>>>>ö
+>>>>>p
+
+query I
+select repeat(a collate de, 10) from tbl order by all;
+----
+oooooooooo
+öööööööööö
+pppppppppp
+
+query I
+select left(b collate de, 6) from tbl order by all;
+----
+>>>>>o
+>>>>>ö
+>>>>>p
+
+query I
+select right(b collate de, 6) from tbl order by all;
+----
+o<<<<<
+ö<<<<<
+p<<<<<
+
+query I
+select right(left(b collate de, 6), 1) from tbl order by all;
+----
+o
+ö
+p
+
+query I
+select reverse(a collate de) from tbl order by all;
+----
+o
+ö
+p
+
+# test application of collation
+query I
+select a from tbl where contains(b collate de, 'o') order by all
+----
+o
+
+query I
+select a from tbl where starts_with(b collate de, '>>>>>o') order by all
+----
+o
+
+query I
+select a from tbl where b collate de like '%>o<%' order by all
+----
+o
+