diff --git a/apps/els_lsp/priv/code_navigation/src/diagnostics_xref_pseudo.erl b/apps/els_lsp/priv/code_navigation/src/diagnostics_xref_pseudo.erl
index 841fce05..a52adcea 100644
--- a/apps/els_lsp/priv/code_navigation/src/diagnostics_xref_pseudo.erl
+++ b/apps/els_lsp/priv/code_navigation/src/diagnostics_xref_pseudo.erl
@@ -14,6 +14,7 @@ main() ->
   unknown_module:module_info(module),
   ?MODULE:behaviour_info(callbacks),
   lager:debug("log message", []),
+  lager:debug_unsafe("log message", []),
   lager:info("log message", []),
   lager:notice("log message", []),
   lager:warning("log message", []),
@@ -23,6 +24,7 @@ main() ->
   lager:emergency("log message", []),
 
   lager:debug("log message"),
+  lager:debug_unsafe("log message", []),
   lager:info("log message"),
   lager:notice("log message"),
   lager:warning("log message"),
diff --git a/apps/els_lsp/src/els_crossref_diagnostics.erl b/apps/els_lsp/src/els_crossref_diagnostics.erl
index 9b08a15a..5e6b03f5 100644
--- a/apps/els_lsp/src/els_crossref_diagnostics.erl
+++ b/apps/els_lsp/src/els_crossref_diagnostics.erl
@@ -22,6 +22,7 @@
 %% Includes
 %%==============================================================================
 -include("els_lsp.hrl").
+-include_lib("kernel/include/logger.hrl").
 %%==============================================================================
 %% Callback Functions
 %%==============================================================================
@@ -32,19 +33,41 @@ is_default() ->
 
 -spec run(uri()) -> [els_diagnostics:diagnostic()].
 run(Uri) ->
-    case els_utils:lookup_document(Uri) of
-        {error, _Error} ->
-            [];
-        {ok, Document} ->
-            POIs = els_dt_document:pois(Document, [
-                application,
-                implicit_fun,
-                import_entry,
-                export_entry,
-                nifs_entry
-            ]),
-            [make_diagnostic(POI) || POI <- POIs, not has_definition(POI, Document)]
-    end.
+    EnabledDiagnostics = els_diagnostics:enabled_diagnostics(),
+    CompilerEnabled = lists:member(<<"compiler">>, EnabledDiagnostics),
+    Start = erlang:monotonic_time(millisecond),
+    Res =
+        case els_utils:lookup_document(Uri) of
+            {error, _Error} ->
+                [];
+            {ok, Document} ->
+                POIs = els_dt_document:pois(Document, kinds()),
+                Opts = #{
+                    compiler_enabled => CompilerEnabled
+                },
+                {Diags, _Cache} =
+                    lists:mapfoldl(
+                        fun(#{id := Id} = POI, Cache) ->
+                            case find_in_cache(Id, Cache) of
+                                {ok, HasDef} ->
+                                    {[make_diagnostic(HasDef, POI)], Cache};
+                                error ->
+                                    HasDef = has_definition(POI, Document, Opts),
+                                    {
+                                        make_diagnostic(HasDef, POI),
+                                        update_cache(HasDef, Id, Cache)
+                                    }
+                            end
+                        end,
+                        #{},
+                        POIs
+                    ),
+                lists:flatten(Diags)
+        end,
+    End = erlang:monotonic_time(millisecond),
+    Duration = End - Start,
+    ?LOG_DEBUG("Crossref done for ~p [duration: ~p ms]", [els_uri:module(Uri), Duration]),
+    Res.
 
 -spec source() -> binary().
 source() ->
@@ -53,106 +76,155 @@ source() ->
 %%==============================================================================
 %% Internal Functions
 %%==============================================================================
--spec make_diagnostic(els_poi:poi()) -> els_diagnostics:diagnostic().
-make_diagnostic(#{range := Range, id := Id}) ->
-    Function =
-        case Id of
-            {F, A} -> lists:flatten(io_lib:format("~p/~p", [F, A]));
-            {M, F, A} -> lists:flatten(io_lib:format("~p:~p/~p", [M, F, A]))
-        end,
-    Message = els_utils:to_binary(
-        io_lib:format(
-            "Cannot find definition for function ~s",
-            [Function]
-        )
-    ),
+-spec update_cache(true | {missing, function | module}, els_poi:poi_id(), map()) -> map().
+update_cache({missing, module}, {M, _F, _A}, Cache) ->
+    %% Cache missing module to avoid repeated lookups
+    Cache#{M => missing};
+update_cache(HasDef, Id, Cache) ->
+    Cache#{Id => HasDef}.
+
+-spec find_in_cache(els_poi:poi_id(), map()) -> _.
+find_in_cache({M, _F, _A}, Cache) when is_map_key(M, Cache) ->
+    {ok, {missing, module}};
+find_in_cache(Id, Cache) ->
+    maps:find(Id, Cache).
+
+-spec kinds() -> [els_poi:poi_kind()].
+kinds() ->
+    [
+        application,
+        implicit_fun,
+        import_entry,
+        export_entry,
+        nifs_entry
+    ].
+
+-spec make_diagnostic(_, els_poi:poi()) -> [els_diagnostics:diagnostic()].
+make_diagnostic({missing, Kind}, #{id := Id} = POI) ->
+    Message = error_msg(Kind, Id),
     Severity = ?DIAGNOSTIC_ERROR,
-    els_diagnostics:make_diagnostic(
-        els_protocol:range(Range),
-        Message,
-        Severity,
-        source()
-    ).
-
--spec has_definition(els_poi:poi(), els_dt_document:item()) -> boolean().
-has_definition(
-    #{
-        kind := application,
-        id := {module_info, 0}
-    },
-    _
-) ->
+    [
+        els_diagnostics:make_diagnostic(
+            els_protocol:range(range(Kind, POI)),
+            Message,
+            Severity,
+            source()
+        )
+    ];
+make_diagnostic(true, _) ->
+    [].
+
+-spec range(module | function, els_poi:poi()) -> els_poi:poi_range().
+range(module, #{data := #{mod_range := Range}}) ->
+    Range;
+range(function, #{data := #{name_range := Range}}) ->
+    Range;
+range(_, #{range := Range}) ->
+    Range.
+
+-spec error_msg(module | function, els_poi:poi_id()) -> binary().
+error_msg(module, {M, _F, _A}) ->
+    els_utils:to_binary(io_lib:format("Cannot find module ~p", [M]));
+error_msg(function, Id) ->
+    els_utils:to_binary(io_lib:format("Cannot find definition for function ~s", [id_str(Id)])).
+
+-spec id_str(els_poi:poi_id()) -> string().
+id_str(Id) ->
+    case Id of
+        {F, A} -> lists:flatten(io_lib:format("~p/~p", [F, A]));
+        {M, F, A} -> lists:flatten(io_lib:format("~p:~p/~p", [M, F, A]))
+    end.
+
+-spec has_definition(els_poi:poi(), els_dt_document:item(), _) ->
+    true | {missing, function | module}.
+has_definition(#{data := #{imported := true}}, _Document, _Opts) ->
+    %% Call to a bif
     true;
-has_definition(
-    #{
-        kind := application,
-        id := {module_info, 1}
-    },
-    _
-) ->
+has_definition(#{id := {module_info, 0}}, _, _) ->
     true;
-has_definition(
-    #{
-        kind := application,
-        data := #{mod_is_variable := true}
-    },
-    _
-) ->
+has_definition(#{id := {module_info, 1}}, _, _) ->
     true;
-has_definition(
-    #{
-        kind := application,
-        id := {Module, module_info, Arity}
-    },
-    _
-) when Arity =:= 0; Arity =:= 1 ->
-    {ok, []} =/= els_dt_document_index:lookup(Module);
-has_definition(
-    #{
-        kind := application,
-        id := {record_info, 2}
-    },
-    _
-) ->
+has_definition(#{data := #{mod_is_variable := true}}, _, _) ->
     true;
-has_definition(
-    #{
-        kind := application,
-        id := {behaviour_info, 1}
-    },
-    _
-) ->
+has_definition(#{data := #{fun_is_variable := true}}, _, _) ->
     true;
-has_definition(
-    #{
-        kind := application,
-        data := #{fun_is_variable := true}
-    },
-    _
-) ->
+has_definition(#{id := {Module, module_info, Arity}}, _, _) when Arity =:= 0; Arity =:= 1 ->
+    case els_dt_document_index:lookup(Module) of
+        {ok, []} ->
+            {missing, module};
+        {ok, _} ->
+            true
+    end;
+has_definition(#{id := {record_info, 2}}, _, _) ->
+    true;
+has_definition(#{id := {behaviour_info, 1}}, _, _) ->
+    true;
+has_definition(#{id := {lager, Level, Arity}}, _, _) ->
+    lager_definition(Level, Arity);
+has_definition(#{id := {lists, append, 1}}, _, _) ->
+    %% lists:append/1 isn't indexed for some reason
     true;
 has_definition(
+    #{id := {F, A}} = POI,
+    Document,
     #{
-        kind := application,
-        id := {lager, Level, Arity}
-    },
-    _
+        %% Compiler already checks local function calls
+        compiler_enabled := false
+    }
 ) ->
-    lager_definition(Level, Arity);
-has_definition(POI, #{uri := Uri}) ->
-    case els_code_navigation:goto_definition(Uri, POI) of
-        {ok, _Defs} ->
+    Uri = els_dt_document:uri(Document),
+    MFA = {els_uri:module(Uri), F, A},
+    case function_lookup(MFA) of
+        true ->
+            true;
+        false ->
+            case els_code_navigation:goto_definition(Uri, POI) of
+                {ok, _Defs} ->
+                    true;
+                {error, _Error} ->
+                    {missing, function}
+            end
+    end;
+has_definition(#{id := {M, _F, _A} = MFA} = POI, _Document, _Opts) ->
+    case function_lookup(MFA) of
+        true ->
             true;
-        {error, _Error} ->
-            false
+        false ->
+            case els_utils:find_module(M) of
+                {ok, Uri} ->
+                    case els_code_navigation:goto_definition(Uri, POI) of
+                        {ok, _Defs} ->
+                            true;
+                        {error, _Error} ->
+                            {missing, function}
+                    end;
+                {error, _} ->
+                    {missing, module}
+            end
+    end;
+has_definition(_POI, #{uri := _Uri}, _Opts) ->
+    true.
+
+-spec function_lookup(mfa()) -> boolean().
+function_lookup(MFA) ->
+    case els_db:lookup(els_dt_functions:name(), MFA) of
+        {ok, []} ->
+            false;
+        {ok, _} ->
+            true
     end.
 
 -spec lager_definition(atom(), integer()) -> boolean().
 lager_definition(Level, Arity) when Arity =:= 1 orelse Arity =:= 2 ->
-    lists:member(Level, lager_levels());
+    case lists:member(Level, lager_levels()) of
+        true ->
+            true;
+        false ->
+            {missing, function}
+    end;
 lager_definition(_, _) ->
-    false.
+    {missing, function}.
 
 -spec lager_levels() -> [atom()].
 lager_levels() ->
-    [debug, info, notice, warning, error, critical, alert, emergency].
+    [debug, debug_unsafe, info, notice, warning, error, critical, alert, emergency].
diff --git a/apps/els_lsp/src/els_db.erl b/apps/els_lsp/src/els_db.erl
index 0d00bab3..a0fca420 100644
--- a/apps/els_lsp/src/els_db.erl
+++ b/apps/els_lsp/src/els_db.erl
@@ -32,6 +32,7 @@ tables() ->
         els_dt_document_index,
         els_dt_references,
         els_dt_signatures,
+        els_dt_functions,
         els_docs_memo
     ].
 
diff --git a/apps/els_lsp/src/els_diagnostics.erl b/apps/els_lsp/src/els_diagnostics.erl
index 8cfb101a..96cb5898 100644
--- a/apps/els_lsp/src/els_diagnostics.erl
+++ b/apps/els_lsp/src/els_diagnostics.erl
@@ -116,11 +116,49 @@ make_diagnostic(Range, Message, Severity, Source, Data) ->
 
 -spec run_diagnostics(uri()) -> [pid()].
 run_diagnostics(Uri) ->
-    [run_diagnostic(Uri, Id) || Id <- enabled_diagnostics()].
+    case is_initial_indexing_done() of
+        true ->
+            ok = wait_for_indexing_job(Uri),
+            [run_diagnostic(Uri, Id) || Id <- enabled_diagnostics()];
+        false ->
+            ?LOG_INFO(
+                "Initial indexing is not done, skip running diagnostics for ~p",
+                [els_uri:module(Uri)]
+            ),
+            []
+    end.
 
 %%==============================================================================
 %% Internal Functions
 %%==============================================================================
+-spec is_initial_indexing_done() -> boolean().
+is_initial_indexing_done() ->
+    %% Keep in sync with els_indexing
+    Jobs = [<<"Applications">>, <<"OTP">>, <<"Dependencies">>],
+    JobTitles = els_background_job:list_titles(),
+    lists:all(
+        fun(Job) ->
+            not lists:member(
+                <<"Indexing ", Job/binary>>,
+                JobTitles
+            )
+        end,
+        Jobs
+    ).
+
+-spec wait_for_indexing_job(uri()) -> ok.
+wait_for_indexing_job(Uri) ->
+    %% Add delay to allowing indexing job to start
+    timer:sleep(10),
+    JobTitles = els_background_job:list_titles(),
+    case lists:member(<<"Indexing ", Uri/binary>>, JobTitles) of
+        false ->
+            %% No indexing job is running, we're ready!
+            ok;
+        true ->
+            %% Indexing job is still running, retry until it finishes
+            wait_for_indexing_job(Uri)
+    end.
 
 -spec run_diagnostic(uri(), diagnostic_id()) -> pid().
 run_diagnostic(Uri, Id) ->
diff --git a/apps/els_lsp/src/els_dt_functions.erl b/apps/els_lsp/src/els_dt_functions.erl
new file mode 100644
index 00000000..8b7b955e
--- /dev/null
+++ b/apps/els_lsp/src/els_dt_functions.erl
@@ -0,0 +1,134 @@
+%%==============================================================================
+%% The 'functions' table
+%%==============================================================================
+-module(els_dt_functions).
+
+%%==============================================================================
+%% Behaviour els_db_table
+%%==============================================================================
+
+-behaviour(els_db_table).
+-export([
+    name/0,
+    opts/0
+]).
+
+%%==============================================================================
+%% API
+%%==============================================================================
+
+-export([
+    insert/1,
+    versioned_insert/1,
+    lookup/1,
+    delete_by_uri/1,
+    versioned_delete_by_uri/2
+]).
+
+%%==============================================================================
+%% Includes
+%%==============================================================================
+-include("els_lsp.hrl").
+-include_lib("stdlib/include/ms_transform.hrl").
+
+%%==============================================================================
+%% Item Definition
+%%==============================================================================
+
+-record(els_dt_functions, {
+    mfa :: mfa() | '_' | {atom(), '_', '_'},
+    version :: version() | '_'
+}).
+-type els_dt_functions() :: #els_dt_functions{}.
+-type version() :: null | integer().
+-type item() :: #{
+    mfa := mfa(),
+    version := version()
+}.
+-export_type([item/0]).
+
+%%==============================================================================
+%% Callbacks for the els_db_table Behaviour
+%%==============================================================================
+
+-spec name() -> atom().
+name() -> ?MODULE.
+
+-spec opts() -> proplists:proplist().
+opts() ->
+    [set].
+
+%%==============================================================================
+%% API
+%%==============================================================================
+
+-spec from_item(item()) -> els_dt_functions().
+from_item(#{
+    mfa := MFA,
+    version := Version
+}) ->
+    #els_dt_functions{
+        mfa = MFA,
+        version = Version
+    }.
+
+-spec to_item(els_dt_functions()) -> item().
+to_item(#els_dt_functions{
+    mfa = MFA,
+    version = Version
+}) ->
+    #{
+        mfa => MFA,
+        version => Version
+    }.
+
+-spec insert(item()) -> ok | {error, any()}.
+insert(Map) when is_map(Map) ->
+    Record = from_item(Map),
+    els_db:write(name(), Record).
+
+-spec versioned_insert(item()) -> ok | {error, any()}.
+versioned_insert(#{mfa := MFA, version := Version} = Map) ->
+    Record = from_item(Map),
+    Condition = fun(#els_dt_functions{version = CurrentVersion}) ->
+        CurrentVersion =:= null orelse Version >= CurrentVersion
+    end,
+    els_db:conditional_write(name(), MFA, Record, Condition).
+
+-spec lookup(mfa()) -> {ok, [item()]}.
+lookup({M, _F, _A} = MFA) ->
+    {ok, _Uris} = els_utils:find_modules(M),
+    {ok, Items} = els_db:lookup(name(), MFA),
+    {ok, [to_item(Item) || Item <- Items]}.
+
+-spec delete_by_uri(uri()) -> ok.
+delete_by_uri(Uri) ->
+    case filename:extension(Uri) of
+        <<".erl">> ->
+            Module = els_uri:module(Uri),
+            Pattern = #els_dt_functions{mfa = {Module, '_', '_'}, _ = '_'},
+            ok = els_db:match_delete(name(), Pattern);
+        _ ->
+            ok
+    end.
+
+-spec versioned_delete_by_uri(uri(), version()) -> ok.
+versioned_delete_by_uri(Uri, Version) ->
+    case filename:extension(Uri) of
+        <<".erl">> ->
+            Module = els_uri:module(Uri),
+            MS = ets:fun2ms(
+                fun
+                    (#els_dt_functions{mfa = {M, _, _}, version = CurrentVersion}) when
+                        M =:= Module,
+                        CurrentVersion =:= null orelse CurrentVersion < Version
+                    ->
+                        true;
+                    (_) ->
+                        false
+                end
+            ),
+            ok = els_db:select_delete(name(), MS);
+        _ ->
+            ok
+    end.
diff --git a/apps/els_lsp/src/els_indexing.erl b/apps/els_lsp/src/els_indexing.erl
index cf793027..99eca4ee 100644
--- a/apps/els_lsp/src/els_indexing.erl
+++ b/apps/els_lsp/src/els_indexing.erl
@@ -101,6 +101,7 @@ deep_index(Document0, UpdateWords) ->
         end,
     case els_dt_document:versioned_insert(Document) of
         ok ->
+            index_functions(Id, Uri, POIs, Version),
             index_signatures(Id, Uri, Text, POIs, Version),
             case Source of
                 otp ->
@@ -133,6 +134,19 @@ index_signature(M, Text, #{id := {F, A}, range := Range, data := #{args := Args}
         args => Args
     }).
 
+-spec index_functions(atom(), uri(), [els_poi:poi()], version()) -> ok.
+index_functions(M, Uri, POIs, Version) ->
+    ok = els_dt_functions:versioned_delete_by_uri(Uri, Version),
+    [index_function(M, POI, Version) || #{kind := function} = POI <- POIs],
+    ok.
+
+-spec index_function(atom(), els_poi:poi(), version()) -> ok.
+index_function(M, #{id := {F, A}}, Version) ->
+    els_dt_functions:versioned_insert(#{
+        mfa => {M, F, A},
+        version => Version
+    }).
+
 -spec index_references(atom(), uri(), [els_poi:poi()], version()) -> ok.
 index_references(Id, Uri, POIs, Version) ->
     ok = els_dt_references:versioned_delete_by_uri(Uri, Version),
@@ -249,8 +263,8 @@ start(Group, Skip, SkipTag, Entries, Source) ->
                 },
                 ?LOG_INFO(
                     "Completed indexing for ~s "
-                    "(succeeded: ~p, skipped: ~p, failed: ~p)",
-                    [Group, Succeeded, Skipped, Failed]
+                    "(succeeded: ~p, skipped: ~p, failed: ~p, duration: ~p ms)",
+                    [Group, Succeeded, Skipped, Failed, Duration]
                 ),
                 els_telemetry:send_notification(Event)
             end
@@ -263,7 +277,8 @@ remove(Uri) ->
     ok = els_dt_document:delete(Uri),
     ok = els_dt_document_index:delete_by_uri(Uri),
     ok = els_dt_references:delete_by_uri(Uri),
-    ok = els_dt_signatures:delete_by_uri(Uri).
+    ok = els_dt_signatures:delete_by_uri(Uri),
+    ok = els_dt_functions:delete_by_uri(Uri).
 
 %%==============================================================================
 %% Internal functions
diff --git a/apps/els_lsp/test/els_diagnostics_SUITE.erl b/apps/els_lsp/test/els_diagnostics_SUITE.erl
index 82ca6351..64f44925 100644
--- a/apps/els_lsp/test/els_diagnostics_SUITE.erl
+++ b/apps/els_lsp/test/els_diagnostics_SUITE.erl
@@ -38,6 +38,7 @@
     escript_warnings/1,
     escript_errors/1,
     crossref/1,
+    crossref_compiler_enabled/1,
     crossref_autoimport/1,
     crossref_autoimport_disabled/1,
     crossref_pseudo_functions/1,
@@ -92,20 +93,22 @@ end_per_suite(Config) ->
 init_per_testcase(TestCase, Config) when
     TestCase =:= atom_typo
 ->
-    meck:new(els_atom_typo_diagnostics, [passthrough, no_link]),
-    meck:expect(els_atom_typo_diagnostics, is_default, 0, true),
-    els_mock_diagnostics:setup(),
-    els_test_utils:init_per_testcase(TestCase, Config);
+    init_with_diagnostics(TestCase, [<<"atom_typo">>], Config);
 init_per_testcase(TestCase, Config) when
     TestCase =:= crossref orelse
         TestCase =:= crossref_pseudo_functions orelse
         TestCase =:= crossref_autoimport orelse
         TestCase =:= crossref_autoimport_disabled
 ->
-    meck:new(els_crossref_diagnostics, [passthrough, no_link]),
-    meck:expect(els_crossref_diagnostics, is_default, 0, true),
-    els_mock_diagnostics:setup(),
-    els_test_utils:init_per_testcase(TestCase, Config);
+    init_with_diagnostics(TestCase, [<<"crossref">>], Config);
+init_per_testcase(TestCase, Config) when
+    TestCase =:= elvis
+->
+    init_with_diagnostics(TestCase, [<<"elvis">>], Config);
+init_per_testcase(TestCase, Config) when
+    TestCase =:= crossref_compiler_enabled
+->
+    init_with_diagnostics(TestCase, [<<"crossref">>, <<"compiler">>], Config);
 init_per_testcase(code_path_extra_dirs, Config) ->
     meck:new(yamerl, [passthrough, no_link]),
     Content = <<"code_path_extra_dirs:\n", "  - \"../code_navigation/*/\"\n">>,
@@ -129,11 +132,10 @@ init_per_testcase(use_long_names_custom_hostname, Config) ->
         <<"runtime:\n", "  use_long_names: true\n", "  cookie: mycookie\n",
             "  node_name: my_node\n", "  hostname: 127.0.0.1">>,
     init_long_names_config(Content, Config);
-init_per_testcase(exclude_unused_includes = TestCase, Config) ->
-    els_mock_diagnostics:setup(),
-    NewConfig = els_test_utils:init_per_testcase(TestCase, Config),
+init_per_testcase(exclude_unused_includes = TestCase, Config0) ->
+    Config = init_with_diagnostics(TestCase, [<<"unused_includes">>], Config0),
     els_config:set(exclude_unused_includes, ["et/include/et.hrl"]),
-    NewConfig;
+    Config;
 init_per_testcase(TestCase, Config) when TestCase =:= compiler_telemetry ->
     els_mock_diagnostics:setup(),
     mock_compiler_telemetry_enabled(),
@@ -193,28 +195,17 @@ init_per_testcase(TestCase, Config) when
 ->
     mock_refactorerl(),
     els_test_utils:init_per_testcase(TestCase, Config);
+init_per_testcase(TestCase, Config) when
+    TestCase =:= unused_includes;
+    TestCase =:= unused_includes_broken;
+    TestCase =:= unused_includes_compiler_attribute
+->
+    init_with_diagnostics(TestCase, [<<"unused_includes">>], Config);
 init_per_testcase(TestCase, Config) ->
     els_mock_diagnostics:setup(),
     els_test_utils:init_per_testcase(TestCase, Config).
 
 -spec end_per_testcase(atom(), config()) -> ok.
-end_per_testcase(TestCase, Config) when
-    TestCase =:= atom_typo
-->
-    meck:unload(els_atom_typo_diagnostics),
-    els_test_utils:end_per_testcase(TestCase, Config),
-    els_mock_diagnostics:teardown(),
-    ok;
-end_per_testcase(TestCase, Config) when
-    TestCase =:= crossref orelse
-        TestCase =:= crossref_pseudo_functions orelse
-        TestCase =:= crossref_autoimport orelse
-        TestCase =:= crossref_autoimport_disabled
-->
-    meck:unload(els_crossref_diagnostics),
-    els_test_utils:end_per_testcase(TestCase, Config),
-    els_mock_diagnostics:teardown(),
-    ok;
 end_per_testcase(TestCase, Config) when
     TestCase =:= code_path_extra_dirs orelse
         TestCase =:= use_long_names orelse
@@ -226,6 +217,7 @@ end_per_testcase(TestCase, Config) when
     els_mock_diagnostics:teardown(),
     ok;
 end_per_testcase(exclude_unused_includes = TestCase, Config) ->
+    reset_diagnostics_config(Config),
     els_config:set(exclude_unused_includes, []),
     els_test_utils:end_per_testcase(TestCase, Config),
     els_mock_diagnostics:teardown(),
@@ -262,6 +254,7 @@ end_per_testcase(TestCase, Config) when
     els_mock_diagnostics:teardown(),
     ok;
 end_per_testcase(TestCase, Config) ->
+    reset_diagnostics_config(Config),
     els_test_utils:end_per_testcase(TestCase, Config),
     els_mock_diagnostics:teardown(),
     ok.
@@ -792,7 +785,23 @@ crossref(_Config) ->
             },
             #{
                 message => <<"Cannot find definition for function lists:map/3">>,
-                range => {{5, 2}, {5, 11}}
+                range => {{5, 8}, {5, 11}}
+            }
+        ],
+    Warnings = [],
+    Hints = [],
+    els_test:run_diagnostics_test(Path, Source, Errors, Warnings, Hints).
+
+-spec crossref_compiler_enabled(config()) -> ok.
+crossref_compiler_enabled(_Config) ->
+    Path = src_path("diagnostics_xref.erl"),
+    Source = <<"CrossRef">>,
+    %% Don't expect diagnostics for missing local functions if compiler is enabled
+    Errors =
+        [
+            #{
+                message => <<"Cannot find definition for function lists:map/3">>,
+                range => {{5, 8}, {5, 11}}
             }
         ],
     Warnings = [],
@@ -806,28 +815,16 @@ crossref_pseudo_functions(_Config) ->
     Errors =
         [
             #{
-                message =>
-                    <<
-                        "Cannot find definition for function "
-                        "unknown_module:nonexistent/0"
-                    >>,
-                range => {{34, 2}, {34, 28}}
+                message => <<"Cannot find module unknown_module">>,
+                range => {{36, 2}, {36, 16}}
             },
             #{
-                message =>
-                    <<
-                        "Cannot find definition for function "
-                        "unknown_module:module_info/1"
-                    >>,
-                range => {{13, 2}, {13, 28}}
+                message => <<"Cannot find module unknown_module">>,
+                range => {{13, 2}, {13, 16}}
             },
             #{
-                message =>
-                    <<
-                        "Cannot find definition for function "
-                        "unknown_module:module_info/0"
-                    >>,
-                range => {{12, 2}, {12, 28}}
+                message => <<"Cannot find module unknown_module">>,
+                range => {{12, 2}, {12, 16}}
             }
         ],
     els_test:run_diagnostics_test(Path, <<"CrossRef">>, Errors, [], []).
@@ -846,7 +843,7 @@ crossref_autoimport_disabled(_Config) ->
     %% This testcase cannot be run from an Erlang source tree version,
     %% it needs a released version.
     Path = src_path("diagnostics_autoimport_disabled.erl"),
-    els_test:run_diagnostics_test(Path, <<"CrossRef">>, [], [], []).
+    els_test:run_diagnostics_test(Path, <<"Quick CrossRef">>, [], [], []).
 
 -spec unused_includes(config()) -> ok.
 unused_includes(_Config) ->
@@ -1156,3 +1153,29 @@ mock_refactorerl() ->
 unmock_refactoerl() ->
     meck:unload(els_refactorerl_diagnostics),
     meck:unload(els_refactorerl_utils).
+
+-spec init_with_diagnostics(atom(), [binary()], config()) -> config().
+init_with_diagnostics(TestCase, Diags, Config0) ->
+    els_mock_diagnostics:setup(),
+    Config = els_test_utils:init_per_testcase(TestCase, Config0),
+    enable_diagnostics(Diags, Config).
+
+%% Enable given diagnostics and disable the rest
+-spec enable_diagnostics([binary()], config()) -> config().
+enable_diagnostics(Diags, Config) ->
+    Available = els_diagnostics:available_diagnostics(),
+    OldDiagnosticsConfig = els_config:get(diagnostics),
+    Disabled = Available -- Diags,
+    DiagConfig = #{"enabled" => Diags, "disabled" => Disabled},
+    els_config:set(diagnostics, DiagConfig),
+    [{old_diagnostics_config, OldDiagnosticsConfig} | Config].
+
+-spec reset_diagnostics_config(config()) -> config().
+reset_diagnostics_config(Config) ->
+    case proplists:get_value(old_diagnostics_config, Config, undefined) of
+        undefined ->
+            Config;
+        DiagnosticsConfig ->
+            ok = els_config:set(diagnostics, DiagnosticsConfig),
+            Config
+    end.