From 3c75844a792a5e1d039c51f0135dad16a96bb1f6 Mon Sep 17 00:00:00 2001
From: Azat Khuzhin <a3at.mail@gmail.com>
Date: Sat, 11 Sep 2021 22:28:46 +0300
Subject: [PATCH] Fix SIGSEGV for arrayCompact() with consts

arrayCompact() implements useDefaultImplementationForConstants() but it
is a no-op for FunctionArrayMapped, fix this.

CI report [1]:

  [1]: https://clickhouse-test-reports.s3.yandex.net/28890/baac2e561cfb05bc174f0bd25571e607d19c7463/fuzzer_asan/report.html#fail1
---
 src/Functions/array/arrayCompact.cpp                            | 2 +-
 .../queries/0_stateless/01020_function_array_compact.reference  | 2 ++
 tests/queries/0_stateless/01020_function_array_compact.sql      | 2 ++
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/Functions/array/arrayCompact.cpp b/src/Functions/array/arrayCompact.cpp
index e0f73207da8..4126f403516 100644
--- a/src/Functions/array/arrayCompact.cpp
+++ b/src/Functions/array/arrayCompact.cpp
@@ -16,7 +16,6 @@ namespace ErrorCodes
 
 struct ArrayCompactImpl
 {
-    static bool useDefaultImplementationForConstants() { return true; }
     static bool needBoolean() { return false; }
     static bool needExpression() { return false; }
     static bool needOneArray() { return false; }
@@ -129,6 +128,7 @@ struct ArrayCompactImpl
     {
         ColumnPtr res;
 
+        mapped = mapped->convertToFullColumnIfConst();
         if (!(executeType< UInt8 >(mapped, array, res) ||
             executeType< UInt16>(mapped, array, res) ||
             executeType< UInt32>(mapped, array, res) ||
diff --git a/tests/queries/0_stateless/01020_function_array_compact.reference b/tests/queries/0_stateless/01020_function_array_compact.reference
index 6627a437251..4a6265b4f55 100644
--- a/tests/queries/0_stateless/01020_function_array_compact.reference
+++ b/tests/queries/0_stateless/01020_function_array_compact.reference
@@ -7,3 +7,5 @@
 [1,2,1]
 [2,1]
 [1,2,3,4,5]
+[0]
+[0]
diff --git a/tests/queries/0_stateless/01020_function_array_compact.sql b/tests/queries/0_stateless/01020_function_array_compact.sql
index eea69dcb6da..d4aaa4d3fca 100644
--- a/tests/queries/0_stateless/01020_function_array_compact.sql
+++ b/tests/queries/0_stateless/01020_function_array_compact.sql
@@ -7,3 +7,5 @@ select arrayCompact([1,1,2]);
 select arrayCompact([1,2,1]);
 select arrayCompact([2,1,1]);
 select arrayCompact([1,2,2,3,3,3,4,4,4,4,5,5,5,5,5]);
+SELECT arrayCompact(x->0, [NULL]);
+SELECT toString(arrayCompact(x->0, [NULL]));