test: extract debug::the_database out

we want to integrate some perf test into scylla executable, so we
can run them on a regular basis. but `test/lib/cql_test_env.cc`
shares `debug::the_database` with `main.cc`, so we cannot just
compile them into a single binary without changing them.

before this change, both `test/lib/cql_test_env.cc`
and `main.cc` define `debug::the_database`.

after this change, `debug::the_database` is extracted into
`debug.cc`, so it compiles into a separate compiling unit.
and scylla and tests using seastar testing framework are linked
against `debug.cc` via `scylla_core` respectively. this paves the road to
integrating scylla with the tests linking aginst
`test/lib/cql_test_env.cc`.

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>

configure.py

@@ -668,6 +668,7 @@ scylla_core = (['message/messaging_service.cc',
                 'caching_options.cc',
                 'collection_mutation.cc',
                 'client_data.cc',
+                'debug.cc',
                 'hashers.cc',
                 'schema.cc',
                 'frozen_schema.cc',

debug.cc

@@ -0,0 +1,15 @@
+/*
+ * Copyright (C) 2023-present ScyllaDB
+ */
+
+/*
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+#include "debug.hh"
+
+namespace debug {
+
+seastar::sharded<replica::database>* the_database = nullptr;
+
+}

main.cc

@@ -435,7 +435,6 @@ sharded<cql3::query_processor>* the_query_processor;
 sharded<qos::service_level_controller>* the_sl_controller;
 sharded<service::migration_manager>* the_migration_manager;
 sharded<service::storage_service>* the_storage_service;
-sharded<replica::database>* the_database;
 sharded<streaming::stream_manager> *the_stream_manager;
 sharded<gms::feature_service> *the_feature_service;
 sharded<gms::gossiper> *the_gossiper;
@@ -1747,7 +1746,7 @@ static main_func_type lookup_main_func(std::string_view name) {
         {"types", tools::scylla_types_main},
         {"sstable", tools::scylla_sstable_main},
     };
-    auto found = std::ranges::find_if(funcs, [name](auto& name_and_func) {
+    auto found = std::ranges::find_if(funcs, [name] (auto& name_and_func) {
         return name_and_func.first == name;
     });
     if (found == std::end(funcs)) {

test/lib/cql_test_env.cc

@@ -973,9 +973,3 @@ cql_test_config raft_cql_test_config() {
     c.db_config->consistent_cluster_management(true);
     return c;
 }
-
-namespace debug {
-
-seastar::sharded<replica::database>* the_database;
-
-}