Merge pull request #50833 from ClickHouse/transform-tests

Add tests for function "transform"

tests/queries/0_stateless/02786_transform_float.reference

@@ -0,0 +1,10 @@
+1
+1
+1
+---
+1
+1
+1
+1
+1
+1

tests/queries/0_stateless/02786_transform_float.sql

@@ -0,0 +1,3 @@
+select transform(number, [1], [toFloat32(1)], toFloat32(1)) from numbers(3);
+SELECT '---';
+select transform(number, [3], [toFloat32(1)], toFloat32(1)) from numbers(6);

tests/queries/0_stateless/02787_transform_null.reference

@@ -0,0 +1,9 @@
+ZERO
+ZERO
+ONE
+ONE
+a
+a
+	\N	0	\N	0	\N
+1	1	1	\N	1	1
+a	\N	3	3	3	3

tests/queries/0_stateless/02787_transform_null.sql

@@ -0,0 +1,40 @@
+SELECT transform(0, [0, 1], ['ZERO', 'ONE'], 'DEFAULT') AS result;
+SELECT transform(0, [0, 1], ['ZERO', 'ONE'], NULL) AS result;
+
+SELECT CASE 1
+  WHEN 0 THEN 'ZERO'
+  WHEN 1 THEN 'ONE'
+  ELSE 'NONE'
+END AS result;
+
+SELECT CASE 1
+  WHEN 0 THEN NULL
+  WHEN 1 THEN 'ONE'
+  ELSE 'NONE'
+END AS result;
+
+select 
+    case 1 
+        when 1 then 'a' 
+        else 'b'
+    end value;
+
+select 
+    case 1 
+        when 1 then 'a' 
+    end value;
+
+SELECT
+    d,
+    toInt16OrNull(d),
+    caseWithExpression(d, 'a', 3, toInt16OrZero(d)) AS case_zero,
+    caseWithExpression(d, 'a', 3, toInt16OrNull(d)) AS case_null,
+    if(d = 'a', 3, toInt16OrZero(d)) AS if_zero,
+    if(d = 'a', 3, toInt16OrNull(d)) AS if_null
+FROM
+(
+    SELECT arrayJoin(['', '1', 'a']) AS d
+)
+ORDER BY
+    case_zero ASC,
+    d ASC;