Backport #59739 to 23.3: Fix leftPad / rightPad function with FixedString input

src/Functions/padString.cpp

@@ -1,5 +1,6 @@
 #include <Columns/ColumnFixedString.h>
 #include <Columns/ColumnString.h>
+#include <DataTypes/DataTypeString.h>
 #include <Functions/FunctionFactory.h>
 #include <Functions/FunctionHelpers.h>
 #include <Functions/GatherUtils/Algorithms.h>
@@ -188,7 +189,7 @@ namespace
                     arguments[2]->getName(),
                     getName());
 
-            return arguments[0];
+            return std::make_shared<DataTypeString>();
         }
 
         ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t input_rows_count) const override

tests/queries/0_stateless/02986_leftpad_fixedstring.reference

@@ -0,0 +1,124 @@
+
+a	String
+
+a	String
+	1	1	1
+61	1	1	1
+6162	1	1	1
+616263	1	1	1
+61626333	1	1	1
+6162633334	1	1	1
+616263333433	1	1	1
+61626333343332	1	1	1
+6162633334333234	1	1	1
+206162633334333234	1	1	1
+20206162633334333234	1	1	1
+2020206162633334333234	1	1	1
+202020206162633334333234	1	1	1
+20202020206162633334333234	1	1	1
+2020202020206162633334333234	1	1	1
+202020202020206162633334333234	1	1	1
+20202020202020206162633334333234	1	1	1
+2020202020202020206162633334333234	1	1	1
+202020202020202020206162633334333234	1	1	1
+20202020202020202020206162633334333234	1	1	1
+	1	1	1
+61	1	1	1
+6162	1	1	1
+616263	1	1	1
+61626333	1	1	1
+6162633334	1	1	1
+616263333433	1	1	1
+61626333343332	1	1	1
+6162633334333234	1	1	1
+616263333433323420	1	1	1
+61626333343332342020	1	1	1
+6162633334333234202020	1	1	1
+616263333433323420202020	1	1	1
+61626333343332342020202020	1	1	1
+6162633334333234202020202020	1	1	1
+616263333433323420202020202020	1	1	1
+61626333343332342020202020202020	1	1	1
+6162633334333234202020202020202020	1	1	1
+616263333433323420202020202020202020	1	1	1
+61626333343332342020202020202020202020	1	1	1
+	1
+61	1
+6162	1
+616263	1
+61626333	1
+6162633334	1
+616263333433	1
+61626333343332	1
+6162633334333234	1
+F09F87AA6162633334333234	1
+F09F87AAF09F87B86162633334333234	1
+F09F87AAF09F87B8F09F87AA6162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B86162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA6162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B86162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA6162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B86162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA6162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B86162633334333234	1
+F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA6162633334333234	1
+	1
+61	1
+6162	1
+616263	1
+61626333	1
+6162633334	1
+616263333433	1
+61626333343332	1
+6162633334333234	1
+6162633334333234F09F87AA	1
+6162633334333234F09F87AAF09F87B8	1
+6162633334333234F09F87AAF09F87B8F09F87AA	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8	1
+6162633334333234F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AAF09F87B8F09F87AA	1
+	1
+F09F87AA	1
+F09F87AAF09F87B8	1
+C391F09F87AAF09F87B8	1
+C391C391F09F87AAF09F87B8	1
+C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391F09F87AAF09F87B8	1
+	1
+F09F87AA	1
+F09F87AAF09F87B8	1
+F09F87AAF09F87B8C391	1
+F09F87AAF09F87B8C391C391	1
+F09F87AAF09F87B8C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391	1
+F09F87AAF09F87B8C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391C391	1

tests/queries/0_stateless/02986_leftpad_fixedstring.sql

@@ -0,0 +1,41 @@
+-- https://github.com/ClickHouse/ClickHouse/issues/59604
+SELECT leftPad(toFixedString('abc', 3), 0), leftPad('abc', CAST('0', 'Int32'));
+SELECT leftPad(toFixedString('abc343243424324', 15), 1) as a, toTypeName(a);
+
+SELECT rightPad(toFixedString('abc', 3), 0), rightPad('abc', CAST('0', 'Int32'));
+SELECT rightPad(toFixedString('abc343243424324', 15), 1) as a, toTypeName(a);
+
+SELECT
+    hex(leftPad(toFixedString('abc34324' as s, 8), number)) as result,
+    hex(leftPad(s, number)) = result,
+    hex(leftPadUTF8(toFixedString(s, 8), number)) = result,
+    hex(leftPadUTF8(s, number)) = result
+FROM numbers(20);
+
+SELECT
+    hex(rightPad(toFixedString('abc34324' as s, 8), number)) as result,
+    hex(rightPad(s, number)) = result,
+    hex(rightPadUTF8(toFixedString(s, 8), number)) = result,
+    hex(rightPadUTF8(s, number)) = result
+FROM numbers(20);
+
+-- I'm not confident the behaviour should be like this. I'm only testing memory problems
+SELECT
+    hex(leftPadUTF8(toFixedString('abc34324' as s, 8), number, '🇪🇸')) as result,
+    hex(leftPadUTF8(s, number, '🇪🇸')) = result
+FROM numbers(20);
+
+SELECT
+    hex(rightPadUTF8(toFixedString('abc34324' as s, 8), number, '🇪🇸')) as result,
+    hex(rightPadUTF8(s, number, '🇪🇸')) = result
+FROM numbers(20);
+
+SELECT
+    hex(leftPadUTF8(toFixedString('🇪🇸' as s, 8), number, 'Ñ')) as result,
+    hex(leftPadUTF8(s, number, 'Ñ')) = result
+FROM numbers(20);
+
+SELECT
+    hex(rightPadUTF8(toFixedString('🇪🇸' as s, 8), number, 'Ñ')) as result,
+    hex(rightPadUTF8(s, number, 'Ñ')) = result
+FROM numbers(20);