should be it

external/duckdb/test/sql/binder/test_alias.test

@@ -0,0 +1,75 @@
+# name: test/sql/binder/test_alias.test
+# description: Test that aliases work properly in renaming columns
+# group: [binder]
+
+statement ok
+SET default_null_order='nulls_first';
+
+statement ok
+PRAGMA enable_verification
+
+statement ok
+CREATE TABLE integers(i INTEGER);
+
+statement ok
+INSERT INTO integers VALUES (1), (2), (3), (NULL)
+
+query IR
+SELECT i % 2 AS p, SUM(i) AS sum_i FROM integers GROUP BY p ORDER BY 1
+----
+NULL	NULL
+0	2.000000
+1	4.000000
+
+query TT
+SELECT alias(i % 2) AS p, alias(SUM(i)) AS sum_i FROM integers GROUP BY p ORDER BY 1
+----
+p	sum_i
+
+query II
+SELECT i + 1 + 1 + 1 AS k, abs(i) AS l FROM integers WHERE i=1 ORDER BY 1
+----
+4	1
+
+query TT
+SELECT alias(i + 1 + 1 + 1) AS k, alias(abs(i)) AS l FROM integers WHERE i=1 ORDER BY 1
+----
+k	l
+
+query TTTT
+SELECT alias(i) AS k, alias(i IN (1)) AS l, alias(i >= 10) AS m, alias(1=0) AS n FROM integers WHERE i=1 ORDER BY 1
+----
+k	l	m	n
+
+query TT
+SELECT alias(CASE WHEN i=1 THEN 19 ELSE 0 END) AS k, alias(i::VARCHAR) AS l FROM integers WHERE i=1 ORDER BY 1
+----
+k	l
+
+statement ok
+CREATE TABLE test (a INTEGER, b INTEGER)
+
+statement ok
+INSERT INTO test VALUES (42, 10), (43, 100);
+
+# check column names for simple projections and aliases
+query IIII
+SELECT a, b, a * 2 AS c, b * (a * 2) AS d FROM test ORDER BY a
+----
+42	10	84	840
+43	100	86	8600
+
+query TTTT
+SELECT alias(a), alias(b), alias(a * 2) AS c, alias(b * (a * 2)) AS d FROM test ORDER BY a
+----
+a	b	c	d
+a	b	c	d
+
+
+# test nested alias in where clause
+query IIII
+select i as b, b as c, c as d, d as e from integers where e = 3;
+----
+3	3	3	3
+
+