diff --git a/CMakeLists.txt b/CMakeLists.txt
index 52e26ebc..97d13160 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -211,6 +211,7 @@ target_sources(ccls PRIVATE
                src/diagnostics_engine.cc
                src/file_consumer.cc
                src/file_contents.cc
+               src/filesystem.cc
                src/fuzzy_match.cc
                src/iindexer.cc
                src/import_manager.cc
diff --git a/index_tests/constructors/constructor.cc b/index_tests/constructors/constructor.cc
index b36665ad..8e26369d 100644
--- a/index_tests/constructors/constructor.cc
+++ b/index_tests/constructors/constructor.cc
@@ -67,7 +67,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 10983126130596230582,
+      "usr": 18410644574635149442,
       "detailed_name": "Foo f",
       "qual_name_offset": 4,
       "short_name": "f",
@@ -80,7 +80,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 17165811951126099095,
+      "usr": 11468802633764653592,
       "detailed_name": "Foo *f2",
       "qual_name_offset": 5,
       "short_name": "f2",
diff --git a/index_tests/constructors/destructor.cc b/index_tests/constructors/destructor.cc
index 59c46409..d750286f 100644
--- a/index_tests/constructors/destructor.cc
+++ b/index_tests/constructors/destructor.cc
@@ -89,7 +89,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 1893354193220338759,
+      "usr": 9954632887635271906,
       "detailed_name": "Foo f",
       "qual_name_offset": 4,
       "short_name": "f",
diff --git a/index_tests/constructors/implicit_constructor.cc b/index_tests/constructors/implicit_constructor.cc
index bd7b719e..06c475c9 100644
--- a/index_tests/constructors/implicit_constructor.cc
+++ b/index_tests/constructors/implicit_constructor.cc
@@ -66,7 +66,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 449111627548814328,
+      "usr": 17348451315735351657,
       "detailed_name": "Type foo0",
       "qual_name_offset": 5,
       "short_name": "foo0",
@@ -79,7 +79,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 17097499197730163115,
+      "usr": 3757978174345638825,
       "detailed_name": "Type foo1",
       "qual_name_offset": 5,
       "short_name": "foo1",
diff --git a/index_tests/constructors/make_functions.cc b/index_tests/constructors/make_functions.cc
index a2c3a4be..9150cc48 100644
--- a/index_tests/constructors/make_functions.cc
+++ b/index_tests/constructors/make_functions.cc
@@ -143,7 +143,7 @@ OUTPUT: make_functions.cc
   "skipped_by_preprocessor": [],
   "types": [{
       "id": 0,
-      "usr": 9281343527065946499,
+      "usr": 7902098450755788854,
       "detailed_name": "T",
       "qual_name_offset": 0,
       "short_name": "T",
@@ -160,7 +160,7 @@ OUTPUT: make_functions.cc
       "uses": ["4:1-4:2|-1|1|4"]
     }, {
       "id": 1,
-      "usr": 10771590811355716928,
+      "usr": 12533159752419999454,
       "detailed_name": "Args",
       "qual_name_offset": 0,
       "short_name": "Args",
@@ -177,7 +177,7 @@ OUTPUT: make_functions.cc
       "uses": ["4:15-4:19|-1|1|4"]
     }, {
       "id": 2,
-      "usr": 11897454629873246477,
+      "usr": 18441628706991062891,
       "detailed_name": "T",
       "qual_name_offset": 0,
       "short_name": "T",
@@ -194,7 +194,7 @@ OUTPUT: make_functions.cc
       "uses": ["9:1-9:2|-1|1|4"]
     }, {
       "id": 3,
-      "usr": 3337128087216004141,
+      "usr": 9441341235704820385,
       "detailed_name": "Args",
       "qual_name_offset": 0,
       "short_name": "Args",
@@ -347,7 +347,7 @@ OUTPUT: make_functions.cc
     }],
   "vars": [{
       "id": 0,
-      "usr": 8463700030555379526,
+      "usr": 15288691366352169805,
       "detailed_name": "Args &&... args",
       "qual_name_offset": 11,
       "short_name": "args",
@@ -359,7 +359,7 @@ OUTPUT: make_functions.cc
       "storage": 1
     }, {
       "id": 1,
-      "usr": 3908732770590594660,
+      "usr": 12338908251430965107,
       "detailed_name": "Args... args",
       "qual_name_offset": 8,
       "short_name": "args",
diff --git a/index_tests/declaration_vs_definition/func_associated_function_params.cc b/index_tests/declaration_vs_definition/func_associated_function_params.cc
index ee705c0d..02287ca8 100644
--- a/index_tests/declaration_vs_definition/func_associated_function_params.cc
+++ b/index_tests/declaration_vs_definition/func_associated_function_params.cc
@@ -53,7 +53,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 14555488990109936920,
+      "usr": 10480417713467708012,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
@@ -66,7 +66,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 10963664335057337329,
+      "usr": 18099600680625658464,
       "detailed_name": "int b",
       "qual_name_offset": 4,
       "short_name": "b",
diff --git a/index_tests/inheritance/class_inherit_templated_parent.cc b/index_tests/inheritance/class_inherit_templated_parent.cc
index 3056a4ff..f106d3c9 100644
--- a/index_tests/inheritance/class_inherit_templated_parent.cc
+++ b/index_tests/inheritance/class_inherit_templated_parent.cc
@@ -102,7 +102,7 @@ OUTPUT:
       "uses": ["13:56-13:64|-1|1|4"]
     }, {
       "id": 5,
-      "usr": 7916588271848318236,
+      "usr": 780719166805015998,
       "detailed_name": "T",
       "qual_name_offset": 0,
       "short_name": "T",
@@ -138,7 +138,7 @@ OUTPUT:
   "funcs": [],
   "vars": [{
       "id": 0,
-      "usr": 12990052348105569112,
+      "usr": 3880651725784125791,
       "detailed_name": "unsigned int T",
       "qual_name_offset": 13,
       "short_name": "T",
diff --git a/index_tests/lambdas/lambda.cc b/index_tests/lambdas/lambda.cc
index 5ed38fa3..c06408f3 100644
--- a/index_tests/lambdas/lambda.cc
+++ b/index_tests/lambdas/lambda.cc
@@ -33,7 +33,7 @@ OUTPUT:
       "uses": []
     }, {
       "id": 1,
-      "usr": 14635009347499519042,
+      "usr": 1287417953265234030,
       "detailed_name": "",
       "qual_name_offset": 0,
       "short_name": "",
@@ -65,7 +65,7 @@ OUTPUT:
       "callees": ["9:14-9:15|1|3|32", "10:14-10:15|1|3|32", "11:14-11:15|1|3|32"]
     }, {
       "id": 1,
-      "usr": 17926497908620168464,
+      "usr": 1328781044864682611,
       "detailed_name": "",
       "qual_name_offset": 0,
       "short_name": "",
@@ -80,7 +80,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 12666114896600231317,
+      "usr": 17270098654620601683,
       "detailed_name": "int x",
       "qual_name_offset": 4,
       "short_name": "x",
@@ -93,7 +93,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 2981279427664991319,
+      "usr": 16806544259835773270,
       "detailed_name": "lambda dosomething",
       "qual_name_offset": 7,
       "short_name": "dosomething",
@@ -106,7 +106,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 2,
-      "usr": 12879188959314906706,
+      "usr": 2034725908368218782,
       "detailed_name": "int y",
       "qual_name_offset": 4,
       "short_name": "y",
diff --git a/index_tests/macros/foo.cc b/index_tests/macros/foo.cc
index f03b19de..4fb7a6e7 100644
--- a/index_tests/macros/foo.cc
+++ b/index_tests/macros/foo.cc
@@ -92,7 +92,7 @@ OUTPUT:
       "storage": 0
     }, {
       "id": 2,
-      "usr": 2056319845419860263,
+      "usr": 14946041066794678724,
       "detailed_name": "DISALLOW",
       "qual_name_offset": 0,
       "short_name": "DISALLOW",
diff --git a/index_tests/namespaces/anonymous_function.cc b/index_tests/namespaces/anonymous_function.cc
index 701ab855..878cb81a 100644
--- a/index_tests/namespaces/anonymous_function.cc
+++ b/index_tests/namespaces/anonymous_function.cc
@@ -26,7 +26,7 @@ OUTPUT:
   "funcs": [{
       "id": 0,
       "usr": 5010253035933134245,
-      "detailed_name": "void (anon)::foo()",
+      "detailed_name": "void (anon ns)::foo()",
       "qual_name_offset": 5,
       "short_name": "foo",
       "kind": 12,
diff --git a/index_tests/namespaces/namespace_alias.cc b/index_tests/namespaces/namespace_alias.cc
index 2c8280f5..15cf5c65 100644
--- a/index_tests/namespaces/namespace_alias.cc
+++ b/index_tests/namespaces/namespace_alias.cc
@@ -150,7 +150,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 6030927277961448585,
+      "usr": 107714981785063096,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
@@ -164,7 +164,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 2,
-      "usr": 7657277353101371136,
+      "usr": 1200087780658383286,
       "detailed_name": "int b",
       "qual_name_offset": 4,
       "short_name": "b",
diff --git a/index_tests/namespaces/namespace_reference.cc b/index_tests/namespaces/namespace_reference.cc
index cf559e1c..5636a6f4 100644
--- a/index_tests/namespaces/namespace_reference.cc
+++ b/index_tests/namespaces/namespace_reference.cc
@@ -111,7 +111,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 3649375698083002347,
+      "usr": 7976909968919750794,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
diff --git a/index_tests/outline/static_function_in_type.cc b/index_tests/outline/static_function_in_type.cc
index 9d05094f..7782eea6 100644
--- a/index_tests/outline/static_function_in_type.cc
+++ b/index_tests/outline/static_function_in_type.cc
@@ -187,7 +187,7 @@ OUTPUT: static_function_in_type.cc
     }],
   "vars": [{
       "id": 0,
-      "usr": 13569879755236306838,
+      "usr": 9285345059965948351,
       "detailed_name": "ns::Manager *m",
       "qual_name_offset": 13,
       "short_name": "m",
diff --git a/index_tests/preprocessor/include_guard.cc b/index_tests/preprocessor/include_guard.cc
index 592fab71..33a82ca3 100644
--- a/index_tests/preprocessor/include_guard.cc
+++ b/index_tests/preprocessor/include_guard.cc
@@ -12,7 +12,7 @@ OUTPUT:
   "funcs": [],
   "vars": [{
       "id": 0,
-      "usr": 11674328179498211370,
+      "usr": 13076155634261037336,
       "detailed_name": "FOO",
       "qual_name_offset": 0,
       "short_name": "FOO",
diff --git a/index_tests/templates/implicit_variable_instantiation.cc b/index_tests/templates/implicit_variable_instantiation.cc
index 42a89405..c268b290 100644
--- a/index_tests/templates/implicit_variable_instantiation.cc
+++ b/index_tests/templates/implicit_variable_instantiation.cc
@@ -87,7 +87,7 @@ OUTPUT:
       "uses": ["10:26-10:32|-1|1|4", "13:13-13:19|-1|1|4", "14:14-14:20|-1|1|4"]
     }, {
       "id": 4,
-      "usr": 2205716167465743256,
+      "usr": 14511917000226829276,
       "detailed_name": "",
       "qual_name_offset": 0,
       "short_name": "",
diff --git a/index_tests/templates/specialization.cc b/index_tests/templates/specialization.cc
index 840493fa..0d667a2d 100644
--- a/index_tests/templates/specialization.cc
+++ b/index_tests/templates/specialization.cc
@@ -83,7 +83,7 @@ OUTPUT:
       "uses": ["7:1-7:9|-1|1|4"]
     }, {
       "id": 2,
-      "usr": 9673599782548740467,
+      "usr": 10862637711685426953,
       "detailed_name": "T",
       "qual_name_offset": 0,
       "short_name": "T",
@@ -100,7 +100,7 @@ OUTPUT:
       "uses": ["5:16-5:17|-1|1|4"]
     }, {
       "id": 3,
-      "usr": 7143192229126273961,
+      "usr": 756188769017350739,
       "detailed_name": "Args",
       "qual_name_offset": 0,
       "short_name": "Args",
@@ -166,7 +166,7 @@ OUTPUT:
       "uses": ["31:1-31:7|-1|1|4"]
     }, {
       "id": 7,
-      "usr": 8880262253425334092,
+      "usr": 3421332160420436276,
       "detailed_name": "T",
       "qual_name_offset": 0,
       "short_name": "T",
@@ -251,7 +251,7 @@ OUTPUT:
       "uses": []
     }, {
       "id": 12,
-      "usr": 14111105212951082474,
+      "usr": 2461355892344618654,
       "detailed_name": "T",
       "qual_name_offset": 0,
       "short_name": "T",
@@ -433,7 +433,7 @@ OUTPUT:
       "storage": 0
     }, {
       "id": 7,
-      "usr": 17826688417349629938,
+      "usr": 10307767688451422448,
       "detailed_name": "T Value",
       "qual_name_offset": 2,
       "short_name": "Value",
diff --git a/index_tests/templates/template_var_usage_folded_into_one.cc b/index_tests/templates/template_var_usage_folded_into_one.cc
index 02e01c73..fd4bd404 100644
--- a/index_tests/templates/template_var_usage_folded_into_one.cc
+++ b/index_tests/templates/template_var_usage_folded_into_one.cc
@@ -71,7 +71,7 @@ OUTPUT:
       "uses": ["8:1-8:2|-1|1|4", "8:11-8:12|-1|1|4"]
     }, {
       "id": 2,
-      "usr": 11919899838872947844,
+      "usr": 8864163146308556810,
       "detailed_name": "",
       "qual_name_offset": 0,
       "short_name": "",
diff --git a/index_tests/usage/func_usage_addr_func.cc b/index_tests/usage/func_usage_addr_func.cc
index e87d6f34..8851f96e 100644
--- a/index_tests/usage/func_usage_addr_func.cc
+++ b/index_tests/usage/func_usage_addr_func.cc
@@ -64,7 +64,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 16088407831770615719,
+      "usr": 13681544683892648258,
       "detailed_name": "void (*)() x",
       "qual_name_offset": 11,
       "short_name": "x",
diff --git a/index_tests/usage/func_usage_addr_method.cc b/index_tests/usage/func_usage_addr_method.cc
index 52d5739c..3babaf65 100644
--- a/index_tests/usage/func_usage_addr_method.cc
+++ b/index_tests/usage/func_usage_addr_method.cc
@@ -67,7 +67,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 4636142131003982569,
+      "usr": 8436636043513449412,
       "detailed_name": "void (Foo::*)() x",
       "qual_name_offset": 16,
       "short_name": "x",
diff --git a/index_tests/usage/func_usage_call_method.cc b/index_tests/usage/func_usage_call_method.cc
index d18cc327..d2d33b00 100644
--- a/index_tests/usage/func_usage_call_method.cc
+++ b/index_tests/usage/func_usage_call_method.cc
@@ -67,7 +67,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 14045150712868309451,
+      "usr": 3014406561587537195,
       "detailed_name": "Foo *f",
       "qual_name_offset": 5,
       "short_name": "f",
diff --git a/index_tests/usage/func_usage_forward_decl_method.cc b/index_tests/usage/func_usage_forward_decl_method.cc
index 1d595bdf..0c5b0bbb 100644
--- a/index_tests/usage/func_usage_forward_decl_method.cc
+++ b/index_tests/usage/func_usage_forward_decl_method.cc
@@ -66,7 +66,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 16229832321010999607,
+      "usr": 12410753116854389823,
       "detailed_name": "Foo *f",
       "qual_name_offset": 5,
       "short_name": "f",
diff --git a/index_tests/usage/type_usage_as_template_parameter.cc b/index_tests/usage/type_usage_as_template_parameter.cc
index 973043fb..e7cdd887 100644
--- a/index_tests/usage/type_usage_as_template_parameter.cc
+++ b/index_tests/usage/type_usage_as_template_parameter.cc
@@ -95,7 +95,7 @@ OUTPUT:
       "storage": 3
     }, {
       "id": 2,
-      "usr": 3364438781074774169,
+      "usr": 2462000803278878465,
       "detailed_name": "unique_ptr<S> *local",
       "qual_name_offset": 15,
       "short_name": "local",
diff --git a/index_tests/usage/type_usage_as_template_parameter_complex.cc b/index_tests/usage/type_usage_as_template_parameter_complex.cc
index e740286d..f5614cc8 100644
--- a/index_tests/usage/type_usage_as_template_parameter_complex.cc
+++ b/index_tests/usage/type_usage_as_template_parameter_complex.cc
@@ -228,7 +228,7 @@ OUTPUT:
       "storage": 2
     }, {
       "id": 1,
-      "usr": 500112618220246,
+      "usr": 11547294959889394856,
       "detailed_name": "unique_ptr<unique_ptr<S1, S2>, S2> *local",
       "qual_name_offset": 36,
       "short_name": "local",
diff --git a/index_tests/usage/type_usage_declare_local.cc b/index_tests/usage/type_usage_declare_local.cc
index b501a77b..2822020d 100644
--- a/index_tests/usage/type_usage_declare_local.cc
+++ b/index_tests/usage/type_usage_declare_local.cc
@@ -63,7 +63,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 16374832544037266261,
+      "usr": 11033478034711123650,
       "detailed_name": "ForwardType *a",
       "qual_name_offset": 13,
       "short_name": "a",
@@ -76,7 +76,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 2580122838476012357,
+      "usr": 8949902309768550158,
       "detailed_name": "ImplementedType b",
       "qual_name_offset": 16,
       "short_name": "b",
diff --git a/index_tests/usage/type_usage_declare_param.cc b/index_tests/usage/type_usage_declare_param.cc
index 60fccd12..b12d9ec3 100644
--- a/index_tests/usage/type_usage_declare_param.cc
+++ b/index_tests/usage/type_usage_declare_param.cc
@@ -60,7 +60,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 13058491096576226774,
+      "usr": 2584795197111552890,
       "detailed_name": "ForwardType *f",
       "qual_name_offset": 13,
       "short_name": "f",
@@ -73,7 +73,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 11055777568039014776,
+      "usr": 5136230284979460117,
       "detailed_name": "ImplementedType a",
       "qual_name_offset": 16,
       "short_name": "a",
diff --git a/index_tests/usage/type_usage_declare_param_prototype.cc b/index_tests/usage/type_usage_declare_param_prototype.cc
index 05b6c4d4..7b16a92f 100644
--- a/index_tests/usage/type_usage_declare_param_prototype.cc
+++ b/index_tests/usage/type_usage_declare_param_prototype.cc
@@ -51,7 +51,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 13823260660189154978,
+      "usr": 2161866804398917919,
       "detailed_name": "Foo *f",
       "qual_name_offset": 5,
       "short_name": "f",
diff --git a/index_tests/usage/type_usage_declare_qualifiers.cc b/index_tests/usage/type_usage_declare_qualifiers.cc
index 799906b3..08621964 100644
--- a/index_tests/usage/type_usage_declare_qualifiers.cc
+++ b/index_tests/usage/type_usage_declare_qualifiers.cc
@@ -48,7 +48,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 7997456978847868736,
+      "usr": 16414210592877294238,
       "detailed_name": "Type &a0",
       "qual_name_offset": 6,
       "short_name": "a0",
@@ -61,7 +61,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 17228576662112939520,
+      "usr": 11558141642862804306,
       "detailed_name": "const Type &a1",
       "qual_name_offset": 12,
       "short_name": "a1",
@@ -74,7 +74,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 2,
-      "usr": 15429032129697337561,
+      "usr": 1536316608590232194,
       "detailed_name": "Type a2",
       "qual_name_offset": 5,
       "short_name": "a2",
@@ -87,7 +87,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 3,
-      "usr": 6081981442495435784,
+      "usr": 316760354845869406,
       "detailed_name": "Type *a3",
       "qual_name_offset": 6,
       "short_name": "a3",
@@ -100,7 +100,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 4,
-      "usr": 5004072032239834773,
+      "usr": 12321730890779907974,
       "detailed_name": "const Type *a4",
       "qual_name_offset": 12,
       "short_name": "a4",
@@ -113,7 +113,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 5,
-      "usr": 14939253431683105646,
+      "usr": 4771437488905761633,
       "detailed_name": "const Type *const a5",
       "qual_name_offset": 18,
       "short_name": "a5",
diff --git a/index_tests/usage/type_usage_various.cc b/index_tests/usage/type_usage_various.cc
index f948a0f7..a2ae182e 100644
--- a/index_tests/usage/type_usage_various.cc
+++ b/index_tests/usage/type_usage_various.cc
@@ -55,7 +55,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 16380484338511689669,
+      "usr": 14873619387499024780,
       "detailed_name": "Foo f",
       "qual_name_offset": 4,
       "short_name": "f",
diff --git a/index_tests/usage/usage_inside_of_call.cc b/index_tests/usage/usage_inside_of_call.cc
index 23988cc3..c005b4bf 100644
--- a/index_tests/usage/usage_inside_of_call.cc
+++ b/index_tests/usage/usage_inside_of_call.cc
@@ -132,7 +132,7 @@ OUTPUT:
       "storage": 0
     }, {
       "id": 2,
-      "usr": 8039186520399841081,
+      "usr": 13284113377394221067,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
diff --git a/index_tests/usage/var_usage_call_function.cc b/index_tests/usage/var_usage_call_function.cc
index e2d4f2fa..1c34a7f2 100644
--- a/index_tests/usage/var_usage_call_function.cc
+++ b/index_tests/usage/var_usage_call_function.cc
@@ -48,7 +48,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 9121974011454213596,
+      "usr": 3510529098767253033,
       "detailed_name": "void (*)() x",
       "qual_name_offset": 11,
       "short_name": "x",
diff --git a/index_tests/usage/var_usage_class_member.cc b/index_tests/usage/var_usage_class_member.cc
index d69730a6..003834a7 100644
--- a/index_tests/usage/var_usage_class_member.cc
+++ b/index_tests/usage/var_usage_class_member.cc
@@ -134,7 +134,7 @@ OUTPUT:
       "storage": 0
     }, {
       "id": 2,
-      "usr": 14669930844300034456,
+      "usr": 16303259148898744165,
       "detailed_name": "Foo f",
       "qual_name_offset": 4,
       "short_name": "f",
diff --git a/index_tests/usage/var_usage_local.cc b/index_tests/usage/var_usage_local.cc
index 009367ea..64b460c6 100644
--- a/index_tests/usage/var_usage_local.cc
+++ b/index_tests/usage/var_usage_local.cc
@@ -42,7 +42,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 14014650769929566957,
+      "usr": 8534460107894911680,
       "detailed_name": "int x",
       "qual_name_offset": 4,
       "short_name": "x",
diff --git a/index_tests/usage/var_usage_shadowed_local.cc b/index_tests/usage/var_usage_shadowed_local.cc
index e63910aa..4e6bbe48 100644
--- a/index_tests/usage/var_usage_shadowed_local.cc
+++ b/index_tests/usage/var_usage_shadowed_local.cc
@@ -47,7 +47,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 13311055950748663970,
+      "usr": 17941402366659878910,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
@@ -60,7 +60,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 14036425367303419504,
+      "usr": 11094102496276744608,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
diff --git a/index_tests/usage/var_usage_shadowed_parameter.cc b/index_tests/usage/var_usage_shadowed_parameter.cc
index b33d417c..2d3194ef 100644
--- a/index_tests/usage/var_usage_shadowed_parameter.cc
+++ b/index_tests/usage/var_usage_shadowed_parameter.cc
@@ -60,7 +60,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 6997229590862003559,
+      "usr": 8011559936501990179,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
diff --git a/index_tests/vars/deduce_auto_type.cc b/index_tests/vars/deduce_auto_type.cc
index 801a2203..cfe0d4fd 100644
--- a/index_tests/vars/deduce_auto_type.cc
+++ b/index_tests/vars/deduce_auto_type.cc
@@ -46,7 +46,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 10601729374837386290,
+      "usr": 9275666070987716270,
       "detailed_name": "Foo *x",
       "qual_name_offset": 5,
       "short_name": "x",
@@ -59,7 +59,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 18422884837902130475,
+      "usr": 16202433437488621027,
       "detailed_name": "Foo *y",
       "qual_name_offset": 5,
       "short_name": "y",
diff --git a/index_tests/vars/function_local.cc b/index_tests/vars/function_local.cc
index 16e4995d..eef83fc4 100644
--- a/index_tests/vars/function_local.cc
+++ b/index_tests/vars/function_local.cc
@@ -44,7 +44,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 13198746475679542317,
+      "usr": 10782632605670042066,
       "detailed_name": "Foo *a",
       "qual_name_offset": 5,
       "short_name": "a",
diff --git a/index_tests/vars/function_param.cc b/index_tests/vars/function_param.cc
index cfd28001..df37bff6 100644
--- a/index_tests/vars/function_param.cc
+++ b/index_tests/vars/function_param.cc
@@ -42,7 +42,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 8730439006497971620,
+      "usr": 4580260577538694711,
       "detailed_name": "Foo *p0",
       "qual_name_offset": 5,
       "short_name": "p0",
@@ -55,7 +55,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 2525014371090380500,
+      "usr": 12071725611268840435,
       "detailed_name": "Foo *p1",
       "qual_name_offset": 5,
       "short_name": "p1",
diff --git a/index_tests/vars/function_shadow_local.cc b/index_tests/vars/function_shadow_local.cc
index 53fa645e..a27f8169 100644
--- a/index_tests/vars/function_shadow_local.cc
+++ b/index_tests/vars/function_shadow_local.cc
@@ -47,7 +47,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 1894874819807168345,
+      "usr": 3440226937504376525,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
@@ -60,7 +60,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 4508045017817092115,
+      "usr": 14700715011944976607,
       "detailed_name": "int a",
       "qual_name_offset": 4,
       "short_name": "a",
diff --git a/index_tests/vars/function_shadow_param.cc b/index_tests/vars/function_shadow_param.cc
index cab3e40d..b4fdf18a 100644
--- a/index_tests/vars/function_shadow_param.cc
+++ b/index_tests/vars/function_shadow_param.cc
@@ -54,7 +54,7 @@ OUTPUT:
       "storage": 1
     }, {
       "id": 1,
-      "usr": 11404600766177939811,
+      "usr": 2147918703972955240,
       "detailed_name": "int p",
       "qual_name_offset": 4,
       "short_name": "p",
diff --git a/index_tests/vars/type_instance_on_using_type.cc b/index_tests/vars/type_instance_on_using_type.cc
index f61dd2c1..654030b4 100644
--- a/index_tests/vars/type_instance_on_using_type.cc
+++ b/index_tests/vars/type_instance_on_using_type.cc
@@ -67,7 +67,7 @@ OUTPUT:
     }],
   "vars": [{
       "id": 0,
-      "usr": 6975456769752895964,
+      "usr": 7730100248624586522,
       "detailed_name": "F a",
       "qual_name_offset": 2,
       "short_name": "a",
diff --git a/src/clang_complete.cc b/src/clang_complete.cc
index 465df042..05a89ed8 100644
--- a/src/clang_complete.cc
+++ b/src/clang_complete.cc
@@ -1,6 +1,7 @@
 #include "clang_complete.h"
 
 #include "clang_utils.h"
+#include "filesystem.hh"
 #include "platform.h"
 #include "timer.h"
 
@@ -27,6 +28,11 @@ unsigned Flags() {
       ;
 }
 
+std::string StripFileType(const std::string& path) {
+  fs::path p(path);
+  return p.parent_path() / p.stem();
+}
+
 unsigned GetCompletionPriority(const CXCompletionString& str,
                                CXCursorKind result_kind,
                                const std::optional<std::string>& typedText) {
@@ -671,12 +677,12 @@ ClangCompleteManager::ClangCompleteManager(Project* project,
       preloaded_sessions_(kMaxPreloadedSessions),
       completion_sessions_(kMaxCompletionSessions) {
   new std::thread([&]() {
-    SetCurrentThreadName("completequery");
+    SetThreadName("completequery");
     CompletionQueryMain(this);
   });
 
   new std::thread([&]() {
-    SetCurrentThreadName("completeparse");
+    SetThreadName("completeparse");
     CompletionParseMain(this);
   });
 }
diff --git a/src/clang_indexer.cc b/src/clang_indexer.cc
index 1167416d..b03ef730 100644
--- a/src/clang_indexer.cc
+++ b/src/clang_indexer.cc
@@ -2304,7 +2304,7 @@ std::vector<std::unique_ptr<IndexFile>> ParseWithTu(
           if (ls_diagnostic.severity != lsDiagnosticSeverity::Error)
             continue;
           ls_diagnostic.range =
-              lsRange(lsPosition(line, 10), lsPosition(line, 10));
+              lsRange{lsPosition{line, 10}, lsPosition{line, 10}};
           param.primary_file->diagnostics_.push_back(ls_diagnostic);
           break;
         }
diff --git a/src/clang_utils.cc b/src/clang_utils.cc
index 2a79b847..b9da4daf 100644
--- a/src/clang_utils.cc
+++ b/src/clang_utils.cc
@@ -15,8 +15,8 @@ lsRange GetLsRangeForFixIt(const CXSourceRange& range) {
   unsigned int end_line, end_column;
   clang_getSpellingLocation(end, nullptr, &end_line, &end_column, nullptr);
 
-  return lsRange(lsPosition(start_line - 1, start_column - 1) /*start*/,
-                 lsPosition(end_line - 1, end_column) /*end*/);
+  return lsRange{lsPosition{int(start_line) - 1, int(start_column) - 1},
+                 lsPosition{int(end_line) - 1, int(end_column)}};
 }
 
 }  // namespace
@@ -59,8 +59,8 @@ std::optional<lsDiagnostic> BuildAndDisposeDiagnostic(CXDiagnostic diagnostic,
 
   // Build diagnostic.
   lsDiagnostic ls_diagnostic;
-  ls_diagnostic.range = lsRange(lsPosition(start_line - 1, start_column - 1),
-                                lsPosition(end_line - 1, end_column - 1));
+  ls_diagnostic.range = lsRange{{int(start_line) - 1, int(start_column) - 1},
+                                {int(end_line) - 1, int(end_column) - 1}};
 
   ls_diagnostic.message = ToString(clang_getDiagnosticSpelling(diagnostic));
 
diff --git a/src/command_line.cc b/src/command_line.cc
index 2cbc311e..6eb15596 100644
--- a/src/command_line.cc
+++ b/src/command_line.cc
@@ -31,9 +31,9 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <functional>
-#include <iostream>
 #include <iterator>
 #include <string>
+#include <thread>
 #include <unordered_map>
 #include <vector>
 
@@ -76,8 +76,7 @@ bool ShouldDisplayMethodTiming(MethodType type) {
 }
 
 void PrintHelp() {
-  std::cout
-      << R"help(ccls is a C/C++/Objective-C language server.
+  printf("%s", R"help(ccls is a C/C++/Objective-C language server.
 
 Mode:
   --test-unit   Run unit tests.
@@ -101,7 +100,7 @@ Other command line options:
                 out.
 
 See more on https://github.com/MaskRay/ccls/wiki
-)help";
+)help");
 }
 
 }  // namespace
@@ -214,7 +213,7 @@ void RunQueryDbThread(const std::string& bin_name,
   }
 
   // Run query db main loop.
-  SetCurrentThreadName("querydb");
+  SetThreadName("querydb");
   while (true) {
     bool did_work = QueryDbMainLoop(
         &db, querydb_waiter, &project, &file_consumer_shared,
@@ -244,11 +243,8 @@ void RunQueryDbThread(const std::string& bin_name,
 //
 // |ipc| is connected to a server.
 void LaunchStdinLoop(std::unordered_map<MethodType, Timer>* request_times) {
-  // If flushing cin requires flushing cout there could be deadlocks in some
-  // clients.
-  std::cin.tie(nullptr);
-
-  StartThread("stdin", [request_times]() {
+  new std::thread([request_times]() {
+    SetThreadName("stdin");
     auto* queue = QueueManager::instance();
     while (true) {
       std::unique_ptr<InMessage> message;
@@ -288,7 +284,8 @@ void LaunchStdinLoop(std::unordered_map<MethodType, Timer>* request_times) {
 
 void LaunchStdoutThread(std::unordered_map<MethodType, Timer>* request_times,
                         MultiQueueWaiter* waiter) {
-  StartThread("stdout", [=]() {
+  new std::thread([=]() {
+    SetThreadName("stdout");
     auto* queue = QueueManager::instance();
 
     while (true) {
@@ -387,9 +384,8 @@ int main(int argc, char** argv) {
       rapidjson::Document reader;
       rapidjson::ParseResult ok = reader.Parse(g_init_options.c_str());
       if (!ok) {
-        std::cerr << "Failed to parse --init as JSON: "
-                  << rapidjson::GetParseError_En(ok.Code()) << " ("
-                  << ok.Offset() << ")\n";
+        fprintf(stderr, "Failed to parse --init as JSON: %s (%zd)\n",
+                rapidjson::GetParseError_En(ok.Code()), ok.Offset());
         return 1;
       }
       JsonReader json_reader{&reader};
@@ -397,9 +393,9 @@ int main(int argc, char** argv) {
         Config config;
         Reflect(json_reader, config);
       } catch (std::invalid_argument& e) {
-        std::cerr << "Fail to parse --init "
-                  << static_cast<JsonReader&>(json_reader).GetPath()
-                  << ", expected " << e.what() << "\n";
+        fprintf(stderr, "Failed to parse --init %s, expected %s\n",
+                static_cast<JsonReader&>(json_reader).GetPath().c_str(),
+                e.what());
         return 1;
       }
     }
diff --git a/src/filesystem.cc b/src/filesystem.cc
new file mode 100644
index 00000000..be32b081
--- /dev/null
+++ b/src/filesystem.cc
@@ -0,0 +1,43 @@
+#include "filesystem.hh"
+
+#include "utils.h"
+
+#include <queue>
+#include <utility>
+
+static void GetFilesInFolderHelper(
+    std::string folder,
+    bool recursive,
+    std::string output_prefix,
+    const std::function<void(const std::string&)>& handler) {
+  std::queue<std::pair<fs::path, fs::path>> q;
+  q.emplace(fs::path(folder), fs::path(output_prefix));
+  while (!q.empty()) {
+    for (auto it = fs::directory_iterator(q.front().first); it != fs::directory_iterator(); ++it) {
+      auto path = it->path();
+      std::string filename = path.filename();
+      if (filename[0] != '.' || filename == ".ccls") {
+        fs::file_status status = it->symlink_status();
+        if (fs::is_regular_file(status))
+          handler(q.front().second / filename);
+        else if (fs::is_directory(status) || fs::is_symlink(status)) {
+          if (recursive) {
+            std::string child_dir = q.front().second / filename;
+            if (fs::is_directory(status))
+              q.push(make_pair(path, child_dir));
+          }
+        }
+      }
+    }
+    q.pop();
+  }
+}
+
+void GetFilesInFolder(std::string folder,
+                      bool recursive,
+                      bool add_folder_to_path,
+                      const std::function<void(const std::string&)>& handler) {
+  EnsureEndsInSlash(folder);
+  GetFilesInFolderHelper(folder, recursive, add_folder_to_path ? folder : "",
+                         handler);
+}
diff --git a/src/filesystem.hh b/src/filesystem.hh
index 0608bd71..dedce15e 100644
--- a/src/filesystem.hh
+++ b/src/filesystem.hh
@@ -1,5 +1,12 @@
 #pragma once
 
 #include <experimental/filesystem>
+#include <functional>
+#include <string>
 
 namespace fs = std::experimental::filesystem;
+
+void GetFilesInFolder(std::string folder,
+                      bool recursive,
+                      bool add_folder_to_path,
+                      const std::function<void(const std::string&)>& handler);
diff --git a/src/include_complete.cc b/src/include_complete.cc
index f9d55f92..f44bedcc 100644
--- a/src/include_complete.cc
+++ b/src/include_complete.cc
@@ -1,11 +1,14 @@
 #include "include_complete.h"
 
+#include "filesystem.hh"
 #include "match.h"
 #include "platform.h"
 #include "project.h"
 #include "standard_includes.h"
 #include "timer.h"
 
+#include <thread>
+
 namespace {
 
 struct CompletionCandidate {
@@ -112,7 +115,8 @@ void IncludeComplete::Rescan() {
                                           g_config->completion.includeBlacklist);
 
   is_scanning = true;
-  StartThread("scan_includes", [this]() {
+  new std::thread([this]() {
+                    SetThreadName("scan_includes");
     Timer timer;
 
     InsertStlIncludes();
diff --git a/src/lex_utils.cc b/src/lex_utils.cc
index deb6ece9..6045eb9d 100644
--- a/src/lex_utils.cc
+++ b/src/lex_utils.cc
@@ -69,21 +69,21 @@ std::pair<bool, int> CaseFoldingSubsequenceMatch(std::string_view search,
 TEST_SUITE("Offset") {
   TEST_CASE("past end") {
     std::string content = "foo";
-    int offset = GetOffsetForPosition(lsPosition(10, 10), content);
+    int offset = GetOffsetForPosition(lsPosition{10, 10}, content);
     REQUIRE(offset <= content.size());
   }
 
   TEST_CASE("in middle of content") {
     std::string content = "abcdefghijk";
     for (int i = 0; i < content.size(); ++i) {
-      int offset = GetOffsetForPosition(lsPosition(0, i), content);
+      int offset = GetOffsetForPosition(lsPosition{0, i}, content);
       REQUIRE(i == offset);
     }
   }
 
   TEST_CASE("at end of content") {
-    REQUIRE(GetOffsetForPosition(lsPosition(0, 0), "") == 0);
-    REQUIRE(GetOffsetForPosition(lsPosition(0, 1), "a") == 1);
+    REQUIRE(GetOffsetForPosition(lsPosition{0, 0}, "") == 0);
+    REQUIRE(GetOffsetForPosition(lsPosition{0, 1}, "a") == 1);
   }
 }
 
diff --git a/src/lsp.cc b/src/lsp.cc
index 251a52d7..1c1c6673 100644
--- a/src/lsp.cc
+++ b/src/lsp.cc
@@ -269,46 +269,9 @@ std::string lsDocumentUri::GetPath() const {
   return ret;
 }
 
-lsPosition::lsPosition() {}
-lsPosition::lsPosition(int line, int character)
-    : line(line), character(character) {}
-
-bool lsPosition::operator==(const lsPosition& other) const {
-  return line == other.line && character == other.character;
-}
-
-bool lsPosition::operator<(const lsPosition& other) const {
-  return line != other.line ? line < other.line : character < other.character;
-}
-
 std::string lsPosition::ToString() const {
   return std::to_string(line) + ":" + std::to_string(character);
 }
-const lsPosition lsPosition::kZeroPosition = lsPosition();
-
-lsRange::lsRange() {}
-lsRange::lsRange(lsPosition start, lsPosition end) : start(start), end(end) {}
-
-bool lsRange::operator==(const lsRange& o) const {
-  return start == o.start && end == o.end;
-}
-
-bool lsRange::operator<(const lsRange& o) const {
-  return !(start == o.start) ? start < o.start : end < o.end;
-}
-
-lsLocation::lsLocation() {}
-lsLocation::lsLocation(lsDocumentUri uri, lsRange range)
-    : uri(uri), range(range) {}
-
-bool lsLocation::operator==(const lsLocation& o) const {
-  return uri == o.uri && range == o.range;
-}
-
-bool lsLocation::operator<(const lsLocation& o) const {
-  return std::make_tuple(uri.raw_uri, range) <
-         std::make_tuple(o.uri.raw_uri, o.range);
-}
 
 bool lsTextEdit::operator==(const lsTextEdit& that) {
   return range == that.range && newText == that.newText;
diff --git a/src/lsp.h b/src/lsp.h
index 32692db3..e3fc6555 100644
--- a/src/lsp.h
+++ b/src/lsp.h
@@ -121,44 +121,42 @@ void Reflect(TVisitor& visitor, lsDocumentUri& value) {
 }
 
 struct lsPosition {
-  lsPosition();
-  lsPosition(int line, int character);
-
-  bool operator==(const lsPosition& other) const;
-  bool operator<(const lsPosition& other) const;
-
-  std::string ToString() const;
-
-  // Note: these are 0-based.
   int line = 0;
   int character = 0;
-  static const lsPosition kZeroPosition;
+  bool operator==(const lsPosition& o) const {
+    return line == o.line && character == o.character;
+  }
+  bool operator<(const lsPosition& o) const {
+    return line != o.line ? line < o.line : character < o.character;
+  }
+  std::string ToString() const;
 };
 MAKE_HASHABLE(lsPosition, t.line, t.character);
 MAKE_REFLECT_STRUCT(lsPosition, line, character);
 
 struct lsRange {
-  lsRange();
-  lsRange(lsPosition start, lsPosition end);
-
-  bool operator==(const lsRange& other) const;
-  bool operator<(const lsRange& other) const;
-
   lsPosition start;
   lsPosition end;
+  bool operator==(const lsRange& o) const {
+    return start == o.start && end == o.end;
+  }
+  bool operator<(const lsRange& o) const {
+    return !(start == o.start) ? start < o.start : end < o.end;
+  }
 };
 MAKE_HASHABLE(lsRange, t.start, t.end);
 MAKE_REFLECT_STRUCT(lsRange, start, end);
 
 struct lsLocation {
-  lsLocation();
-  lsLocation(lsDocumentUri uri, lsRange range);
-
-  bool operator==(const lsLocation& other) const;
-  bool operator<(const lsLocation& o) const;
-
   lsDocumentUri uri;
   lsRange range;
+  bool operator==(const lsLocation& o) const {
+    return uri == o.uri && range == o.range;
+  }
+  bool operator<(const lsLocation& o) const {
+    return !(uri.raw_uri == o.uri.raw_uri) ? uri.raw_uri < o.uri.raw_uri
+                                           : range < o.range;
+  }
 };
 MAKE_HASHABLE(lsLocation, t.uri, t.range);
 MAKE_REFLECT_STRUCT(lsLocation, uri, range);
diff --git a/src/message_handler.cc b/src/message_handler.cc
index 78b32eec..7c0fd96e 100644
--- a/src/message_handler.cc
+++ b/src/message_handler.cc
@@ -332,8 +332,8 @@ void EmitSemanticHighlighting(QueryDatabase* db,
     // Attribute range [events[i-1].pos, events[i].pos) to events[top-1].symbol
     // .
     if (top && !(events[i - 1].pos == events[i].pos))
-      events[top - 1].symbol->ranges.emplace_back(events[i - 1].pos,
-                                                  events[i].pos);
+      events[top - 1].symbol->ranges.push_back(
+          lsRange{events[i - 1].pos, events[i].pos});
     if (events[i].id >= 0)
       events[top++] = events[i];
     else
diff --git a/src/messages/initialize.cc b/src/messages/initialize.cc
index 37440fa9..d2aa5167 100644
--- a/src/messages/initialize.cc
+++ b/src/messages/initialize.cc
@@ -517,11 +517,12 @@ struct Handler_Initialize : BaseMessageHandler<In_InitializeRequest> {
             std::max(int(std::thread::hardware_concurrency() * 0.8), 1);
       }
       LOG_S(INFO) << "Starting " << g_config->index.threads << " indexers";
-      for (int i = 0; i < g_config->index.threads; ++i) {
-        StartThread("indexer" + std::to_string(i), [=]() {
-          Indexer_Main(diag_engine, file_consumer_shared,
-                       timestamp_manager, import_manager,
-                       import_pipeline_status, project, working_files, waiter);
+      for (int i = 0; i < g_config->index.threads; i++) {
+        new std::thread([=]() {
+          SetThreadName("indexer" + std::to_string(i));
+          Indexer_Main(diag_engine, file_consumer_shared, timestamp_manager,
+                       import_manager, import_pipeline_status, project,
+                       working_files, waiter);
         });
       }
 
diff --git a/src/platform.h b/src/platform.h
index e2903606..b8a36bf3 100644
--- a/src/platform.h
+++ b/src/platform.h
@@ -12,7 +12,7 @@ void PlatformInit();
 std::string GetExecutablePath();
 std::string NormalizePath(const std::string& path);
 
-void SetCurrentThreadName(const std::string& thread_name);
+void SetThreadName(const std::string& thread_name);
 
 std::optional<int64_t> GetLastModificationTime(const std::string& absolute_path);
 
diff --git a/src/platform_posix.cc b/src/platform_posix.cc
index ea9da8ca..6af30d70 100644
--- a/src/platform_posix.cc
+++ b/src/platform_posix.cc
@@ -155,7 +155,7 @@ std::string NormalizePath(const std::string& path) {
   return resolved ? *resolved : path;
 }
 
-void SetCurrentThreadName(const std::string& thread_name) {
+void SetThreadName(const std::string& thread_name) {
   loguru::set_thread_name(thread_name.c_str());
 #if defined(__APPLE__)
   pthread_setname_np(thread_name.c_str());
diff --git a/src/platform_win.cc b/src/platform_win.cc
index c6c4df3f..f4c71a95 100644
--- a/src/platform_win.cc
+++ b/src/platform_win.cc
@@ -15,7 +15,6 @@
 
 #include <algorithm>
 #include <cassert>
-#include <iostream>
 #include <string>
 
 void PlatformInit() {
@@ -60,7 +59,7 @@ typedef struct tagTHREADNAME_INFO {
   DWORD dwFlags;     // Reserved for future use, must be zero.
 } THREADNAME_INFO;
 #pragma pack(pop)
-void SetCurrentThreadName(const std::string& thread_name) {
+void SetThreadName(const std::string& thread_name) {
   loguru::set_thread_name(thread_name.c_str());
 
   THREADNAME_INFO info;
diff --git a/src/project.cc b/src/project.cc
index 74790c75..4ced67fb 100644
--- a/src/project.cc
+++ b/src/project.cc
@@ -21,6 +21,7 @@
 #include <unistd.h>
 #endif
 
+#include <fstream>
 #include <limits>
 #include <unordered_set>
 #include <vector>
@@ -47,7 +48,7 @@ struct ProjectConfig {
   std::unordered_set<std::string> quote_dirs;
   std::unordered_set<std::string> angle_dirs;
   std::vector<std::string> extra_flags;
-  std::string project_dir;
+  fs::path project_dir;
   ProjectMode mode = ProjectMode::CompileCommandsJson;
 };
 
@@ -107,7 +108,7 @@ Project::Entry GetCompilationEntryFromCompileCommandEntry(
     const CompileCommandsEntry& entry) {
   Project::Entry result;
   result.filename = entry.file;
-  const std::string base_name = GetBaseName(entry.file);
+  const std::string base_name = fs::path(entry.file).filename();
 
   // Expand %c %cpp %clang
   std::vector<std::string> args;
@@ -256,7 +257,8 @@ Project::Entry GetCompilationEntryFromCompileCommandEntry(
 std::vector<std::string> ReadCompilerArgumentsFromFile(
     const std::string& path) {
   std::vector<std::string> args;
-  for (std::string line : ReadFileLines(path)) {
+  std::ifstream fin(path);
+  for (std::string line; std::getline(fin, line);) {
     TrimInPlace(line);
     if (line.empty() || StartsWith(line, "#"))
       continue;
@@ -268,7 +270,7 @@ std::vector<std::string> ReadCompilerArgumentsFromFile(
 std::vector<Project::Entry> LoadFromDirectoryListing(ProjectConfig* config) {
   std::vector<Project::Entry> result;
   config->mode = ProjectMode::DotCcls;
-  LOG_IF_S(WARNING, !FileExists(config->project_dir + "/.ccls") &&
+  LOG_IF_S(WARNING, !fs::exists(config->project_dir / ".ccls") &&
                         config->extra_flags.empty())
       << "ccls has no clang arguments. Considering adding either a "
          "compile_commands.json or .ccls file. See the ccls README for "
@@ -282,31 +284,31 @@ std::vector<Project::Entry> LoadFromDirectoryListing(ProjectConfig* config) {
                    [&folder_args, &files](const std::string& path) {
                      if (SourceFileLanguage(path) != LanguageId::Unknown) {
                        files.push_back(path);
-                     } else if (GetBaseName(path) == ".ccls") {
+                     } else if (fs::path(path).filename() == ".ccls") {
                        LOG_S(INFO) << "Using .ccls arguments from " << path;
-                       folder_args.emplace(GetDirName(path),
-                                           ReadCompilerArgumentsFromFile(path));
+                       folder_args.emplace(
+                           fs::path(path).parent_path().string(),
+                           ReadCompilerArgumentsFromFile(path));
                      }
                    });
 
-  const auto& project_dir_args = folder_args[config->project_dir];
+  const std::string project_dir = config->project_dir.string();
+  const auto& project_dir_args = folder_args[project_dir];
   LOG_IF_S(INFO, !project_dir_args.empty())
       << "Using .ccls arguments " << StringJoin(project_dir_args);
 
-  auto GetCompilerArgumentForFile = [&config,
-                                     &folder_args](const std::string& path) {
-    for (std::string cur = GetDirName(path);; cur = GetDirName(cur)) {
+  auto GetCompilerArgumentForFile = [&project_dir, &folder_args](fs::path cur) {
+    while (!(cur = cur.parent_path()).empty()) {
       auto it = folder_args.find(cur);
       if (it != folder_args.end())
         return it->second;
       std::string normalized = NormalizePath(cur);
       // Break if outside of the project root.
-      if (normalized.size() <= config->project_dir.size() ||
-          normalized.compare(0, config->project_dir.size(),
-                             config->project_dir) != 0)
+      if (normalized.size() <= project_dir.size() ||
+          normalized.compare(0, project_dir.size(), project_dir) != 0)
         break;
     }
-    return folder_args[config->project_dir];
+    return folder_args[project_dir];
   };
 
   for (const std::string& file : files) {
@@ -327,7 +329,7 @@ std::vector<Project::Entry> LoadCompilationEntriesFromDirectory(
     ProjectConfig* project,
     const std::string& opt_compilation_db_dir) {
   // If there is a .ccls file always load using directory listing.
-  if (FileExists(project->project_dir + ".ccls"))
+  if (fs::exists(project->project_dir / ".ccls"))
     return LoadFromDirectoryListing(project);
 
   // If |compilationDatabaseCommand| is specified, execute it to get the compdb.
@@ -335,7 +337,7 @@ std::vector<Project::Entry> LoadCompilationEntriesFromDirectory(
   if (g_config->compilationDatabaseCommand.empty()) {
     project->mode = ProjectMode::CompileCommandsJson;
     // Try to load compile_commands.json, but fallback to a project listing.
-    comp_db_dir = opt_compilation_db_dir.empty() ? project->project_dir
+    comp_db_dir = opt_compilation_db_dir.empty() ? project->project_dir.string()
                                                  : opt_compilation_db_dir;
   } else {
     project->mode = ProjectMode::ExternalCommand;
@@ -522,11 +524,14 @@ Project::Entry Project::FindCompilationEntryForFile(
 
     // |best_entry| probably has its own path in the arguments. We need to remap
     // that path to the new filename.
-    std::string best_entry_base_name = GetBaseName(best_entry->filename);
+    fs::path best_entry_base_name = fs::path(best_entry->filename).filename();
     for (std::string& arg : result.args) {
-      if (arg == best_entry->filename ||
-          GetBaseName(arg) == best_entry_base_name) {
-        arg = filename;
+      try {
+        if (arg == best_entry->filename ||
+            fs::path(arg).filename() == best_entry_base_name) {
+          arg = filename;
+        }
+      } catch (...) {
       }
     }
   }
@@ -669,7 +674,7 @@ TEST_SUITE("Project") {
                   "--foobar",
                   "-Ia_relative1",
                   "--foobar",
-                  "-I",
+                  "-isystem",
                   "a_relative2",
                   "--foobar",
                   "-iquote/q_absolute1",
@@ -691,7 +696,8 @@ TEST_SUITE("Project") {
         "/a_absolute1", "/a_absolute2", "/base/a_relative1",
         "/base/a_relative2"};
     std::unordered_set<std::string> quote_expected{
-        "/q_absolute1", "/q_absolute2", "/base/q_relative1",
+        "/a_absolute1",     "/a_absolute2", "/base/a_relative1",
+        "/q_absolute1",     "/q_absolute2", "/base/q_relative1",
         "/base/q_relative2"};
     REQUIRE(config.angle_dirs == angle_expected);
     REQUIRE(config.quote_dirs == quote_expected);
diff --git a/src/query_utils.cc b/src/query_utils.cc
index a016fedc..bf61ba64 100644
--- a/src/query_utils.cc
+++ b/src/query_utils.cc
@@ -158,19 +158,19 @@ std::vector<Use> GetUsesForAllDerived(QueryDatabase* db, QueryFunc& root) {
 std::optional<lsPosition> GetLsPosition(WorkingFile* working_file,
                                    const Position& position) {
   if (!working_file)
-    return lsPosition(position.line, position.column);
+    return lsPosition{position.line, position.column};
 
   int column = position.column;
   if (std::optional<int> start =
           working_file->GetBufferPosFromIndexPos(position.line, &column, false))
-    return lsPosition(*start, column);
+    return lsPosition{*start, column};
   return std::nullopt;
 }
 
 std::optional<lsRange> GetLsRange(WorkingFile* working_file, const Range& location) {
   if (!working_file) {
-    return lsRange(lsPosition(location.start.line, location.start.column),
-                   lsPosition(location.end.line, location.end.column));
+    return lsRange{lsPosition{location.start.line, location.start.column},
+                   lsPosition{location.end.line, location.end.column}};
   }
 
   int start_column = location.start.column, end_column = location.end.column;
@@ -192,8 +192,8 @@ std::optional<lsRange> GetLsRange(WorkingFile* working_file, const Range& locati
   if (*start == *end && start_column > end_column)
     end_column = start_column;
 
-  return lsRange(lsPosition(*start, start_column),
-                 lsPosition(*end, end_column));
+  return lsRange{lsPosition{*start, start_column},
+                 lsPosition{*end, end_column}};
 }
 
 lsDocumentUri GetLsDocumentUri(QueryDatabase* db,
@@ -227,7 +227,7 @@ std::optional<lsLocation> GetLsLocation(QueryDatabase* db,
       GetLsRange(working_files->GetFileByFilename(path), use.range);
   if (!range)
     return std::nullopt;
-  return lsLocation(uri, *range);
+  return lsLocation{uri, *range};
 }
 
 std::optional<lsLocationEx> GetLsLocationEx(QueryDatabase* db,
diff --git a/src/serializer.cc b/src/serializer.cc
index 391a5999..978e2550 100644
--- a/src/serializer.cc
+++ b/src/serializer.cc
@@ -1,11 +1,11 @@
 #include "serializer.h"
 
+#include "filesystem.hh"
 #include "serializers/json.h"
 #include "serializers/msgpack.h"
 
 #include "indexer.h"
 
-#include <doctest/doctest.h>
 #include <loguru.hpp>
 
 #include <stdexcept>
@@ -153,7 +153,7 @@ void Reflect(Writer& visitor, IndexInclude& value) {
   REFLECT_MEMBER_START();
   REFLECT_MEMBER(line);
   if (gTestOutputMode) {
-    std::string basename = GetBaseName(value.resolved_path);
+    std::string basename = fs::path(value.resolved_path).filename();
     if (!StartsWith(value.resolved_path, "&"))
       basename = "&" + basename;
     REFLECT_MEMBER2("resolved_path", basename);
@@ -279,7 +279,7 @@ bool ReflectMemberStart(Writer& visitor, IndexFile& value) {
     assert(value.Resolve(it->second)->uses.size() == 0);
   }
 
-  DefaultReflectMemberStart(visitor);
+  visitor.StartObject();
   return true;
 }
 template <typename TVisitor>
@@ -441,17 +441,3 @@ std::unique_ptr<IndexFile> Deserialize(
 
   return file;
 }
-
-void SetTestOutputMode() {
-  gTestOutputMode = true;
-}
-
-TEST_SUITE("Serializer utils") {
-  TEST_CASE("GetBaseName") {
-    REQUIRE(GetBaseName("foo.cc") == "foo.cc");
-    REQUIRE(GetBaseName("foo/foo.cc") == "foo.cc");
-    REQUIRE(GetBaseName("/foo.cc") == "foo.cc");
-    REQUIRE(GetBaseName("///foo.cc") == "foo.cc");
-    REQUIRE(GetBaseName("bar/") == ".");
-  }
-}
diff --git a/src/serializer.h b/src/serializer.h
index b2b9b65c..5807a595 100644
--- a/src/serializer.h
+++ b/src/serializer.h
@@ -25,7 +25,6 @@ class Reader {
 
   virtual bool IsBool() = 0;
   virtual bool IsNull() = 0;
-  virtual bool IsArray() = 0;
   virtual bool IsInt() = 0;
   virtual bool IsInt64() = 0;
   virtual bool IsUint64() = 0;
@@ -73,7 +72,6 @@ struct IndexFile;
 
 #define REFLECT_MEMBER_START() ReflectMemberStart(visitor, value)
 #define REFLECT_MEMBER_END() ReflectMemberEnd(visitor, value);
-#define REFLECT_MEMBER_END1(value) ReflectMemberEnd(visitor, value);
 #define REFLECT_MEMBER(name) ReflectMember(visitor, #name, value.name)
 #define REFLECT_MEMBER2(name, value) ReflectMember(visitor, name, value)
 
@@ -315,11 +313,6 @@ void Reflect(Writer& visitor, std::vector<T>& values) {
 
 // ReflectMember
 
-inline void DefaultReflectMemberStart(Writer& visitor) {
-  visitor.StartObject();
-}
-inline void DefaultReflectMemberStart(Reader& visitor) {}
-
 template <typename T>
 bool ReflectMemberStart(Reader& visitor, T& value) {
   return false;
@@ -356,5 +349,3 @@ std::unique_ptr<IndexFile> Deserialize(
     const std::string& serialized_index_content,
     const std::string& file_content,
     std::optional<int> expected_version);
-
-void SetTestOutputMode();
diff --git a/src/serializers/json.h b/src/serializers/json.h
index 47e3b035..aa9d5f0f 100644
--- a/src/serializers/json.h
+++ b/src/serializers/json.h
@@ -15,7 +15,6 @@ class JsonReader : public Reader {
 
   bool IsBool() override { return m_->IsBool(); }
   bool IsNull() override { return m_->IsNull(); }
-  bool IsArray() override { return m_->IsArray(); }
   bool IsInt() override { return m_->IsInt(); }
   bool IsInt64() override { return m_->IsInt64(); }
   bool IsUint64() override { return m_->IsUint64(); }
diff --git a/src/serializers/msgpack.h b/src/serializers/msgpack.h
index f9b1666b..83ea5983 100644
--- a/src/serializers/msgpack.h
+++ b/src/serializers/msgpack.h
@@ -23,7 +23,6 @@ class MessagePackReader : public Reader {
 
   bool IsBool() override { return oh_.get().type == msgpack::type::BOOLEAN; }
   bool IsNull() override { return oh_.get().is_nil(); }
-  bool IsArray() override { return oh_.get().type == msgpack::type::ARRAY; }
   bool IsInt() override {
     return oh_.get().type == msgpack::type::POSITIVE_INTEGER ||
            oh_.get().type == msgpack::type::NEGATIVE_INTEGER;
diff --git a/src/test.cc b/src/test.cc
index f94e447e..a8075815 100644
--- a/src/test.cc
+++ b/src/test.cc
@@ -1,5 +1,6 @@
 #include "test.h"
 
+#include "filesystem.hh"
 #include "indexer.h"
 #include "platform.h"
 #include "serializer.h"
@@ -15,7 +16,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <fstream>
-#include <iostream>
 
 // The 'diff' utility is available and we can use dprintf(3).
 #if _POSIX_C_SOURCE >= 200809L
@@ -23,6 +23,8 @@
 #include <unistd.h>
 #endif
 
+extern bool gTestOutputMode;
+
 std::string ToString(const rapidjson::Document& document) {
   rapidjson::StringBuffer buffer;
   rapidjson::PrettyWriter<rapidjson::StringBuffer> writer(buffer);
@@ -35,6 +37,33 @@ std::string ToString(const rapidjson::Document& document) {
   return buffer.GetString();
 }
 
+struct TextReplacer {
+  struct Replacement {
+    std::string from;
+    std::string to;
+  };
+
+  std::vector<Replacement> replacements;
+
+  std::string Apply(const std::string& content) {
+    std::string result = content;
+
+    for (const Replacement& replacement : replacements) {
+      while (true) {
+        size_t idx = result.find(replacement.from);
+        if (idx == std::string::npos)
+          break;
+
+        result.replace(result.begin() + idx,
+          result.begin() + idx + replacement.from.size(),
+          replacement.to);
+      }
+    }
+
+    return result;
+  }
+};
+
 void ParseTestExpectation(
     const std::string& filename,
     const std::vector<std::string>& lines_with_endings,
@@ -125,8 +154,7 @@ void DiffDocuments(std::string path,
                    rapidjson::Document& actual) {
   std::string joined_actual_output = ToString(actual);
   std::string joined_expected_output = ToString(expected);
-  std::cout << "[FAILED] " << path << " (section " << path_section << ")"
-            << std::endl;
+  printf("[FAILED] %s (section %s)\n", path.c_str(), path_section.c_str());
 
 #if _POSIX_C_SOURCE >= 200809L
   char expected_file[] = "/tmp/ccls.expected.XXXXXX";
@@ -156,13 +184,10 @@ void DiffDocuments(std::string path,
   std::vector<std::string> expected_output =
       SplitString(joined_expected_output, "\n");
 
-  std::cout << "Expected output for " << path << " (section " << path_section
-            << "):" << std::endl;
-  std::cout << joined_expected_output << std::endl;
-  std::cout << "Actual output for " << path << " (section " << path_section
-            << "):" << std::endl;
-  std::cout << joined_actual_output << std::endl;
-  std::cout << std::endl;
+  printf("Expected output for %s (section %s)\n:%s\n", path.c_str(),
+         path_section.c_str(), joined_expected_output.c_str());
+  printf("Actual output for %s (section %s)\n:%s\n", path.c_str(),
+         path_section.c_str(), joined_actual_output.c_str());
 }
 
 void VerifySerializeToFrom(IndexFile* file) {
@@ -173,7 +198,7 @@ void VerifySerializeToFrom(IndexFile* file) {
                   std::nullopt /*expected_version*/);
   std::string actual = result->ToString();
   if (expected != actual) {
-    std::cerr << "Serialization failure" << std::endl;
+    fprintf(stderr, "Serialization failure\n");
     assert(false);
   }
 }
@@ -186,7 +211,7 @@ std::string FindExpectedOutputForFilename(
       return entry.second;
   }
 
-  std::cerr << "Couldn't find expected output for " << filename << std::endl;
+  fprintf(stderr, "Couldn't find expected output for %s\n", filename.c_str());
   getchar();
   getchar();
   return "{}";
@@ -203,16 +228,17 @@ IndexFile* FindDbForPathEnding(
 }
 
 bool RunIndexTests(const std::string& filter_path, bool enable_update) {
-  SetTestOutputMode();
+  gTestOutputMode = true;
 
   // Index tests change based on the version of clang used.
-  static constexpr const char* kRequiredClangVersion =
+  static const char kRequiredClangVersion[] =
       "clang version 6.0.0 (tags/RELEASE_600/final)";
   if (GetClangVersion() != kRequiredClangVersion &&
       GetClangVersion().find("trunk") == std::string::npos) {
-    std::cerr << "Index tests must be run using clang version \""
-              << kRequiredClangVersion << "\" (ccls is running with \""
-              << GetClangVersion() << "\")" << std::endl;
+    fprintf(stderr,
+            "Index tests must be run using clang version %s, ccls is running "
+            "with %s\n",
+            kRequiredClangVersion, GetClangVersion().c_str());
     return false;
   }
 
@@ -221,141 +247,141 @@ bool RunIndexTests(const std::string& filter_path, bool enable_update) {
   // FIXME: show diagnostics in STL/headers when running tests. At the moment
   // this can be done by constructing ClangIndex index(1, 1);
   ClangIndex index;
-  for (std::string path : GetFilesInFolder("index_tests", true /*recursive*/,
-                                           true /*add_folder_to_path*/)) {
-    bool is_fail_allowed = false;
+  GetFilesInFolder(
+      "index_tests", true /*recursive*/, true /*add_folder_to_path*/,
+      [&](const std::string& path) {
+        bool is_fail_allowed = false;
 
-    if (EndsWithAny(path, {".m", ".mm"})) {
+        if (EndsWithAny(path, {".m", ".mm"})) {
 #ifndef __APPLE__
-      std::cout << "Skipping \"" << path << "\" since this platform does not "
-                  << "support running Objective-C tests." << std::endl;
-      continue;
+          return;
 #endif
 
-      // objective-c tests are often not updated right away. do not bring down
-      // CI if they fail.
-      if (!enable_update)
-        is_fail_allowed = true;
-    }
-
-    if (path.find(filter_path) == std::string::npos)
-      continue;
-
-    if (!filter_path.empty())
-      std::cout << "Running " << path << std::endl;
-
-    // Parse expected output from the test, parse it into JSON document.
-    std::vector<std::string> lines_with_endings = ReadFileLines(path);
-    TextReplacer text_replacer;
-    std::vector<std::string> flags;
-    std::unordered_map<std::string, std::string> all_expected_output;
-    ParseTestExpectation(path, lines_with_endings, &text_replacer, &flags,
-                         &all_expected_output);
-
-    // Build flags.
-    bool had_extra_flags = !flags.empty();
-    if (!AnyStartsWith(flags, "-x"))
-      flags.push_back("-xc++");
-    flags.push_back("-resource-dir=" + GetDefaultResourceDirectory());
-    if (had_extra_flags) {
-      std::cout << "For " << path << std::endl;
-      std::cout << "  flags: " << StringJoin(flags) << std::endl;
-    }
-    flags.push_back(path);
-
-    // Run test.
-    g_config = std::make_unique<Config>();
-    FileConsumerSharedState file_consumer_shared;
-    PerformanceImportFile perf;
-    auto dbs = Parse(&file_consumer_shared, path, flags, {}, &perf, &index,
-                     false /*dump_ast*/);
-
-    for (const auto& entry : all_expected_output) {
-      const std::string& expected_path = entry.first;
-      std::string expected_output = text_replacer.Apply(entry.second);
-
-      // FIXME: promote to utils, find and remove duplicates (ie,
-      // ccls_call_tree.cc, maybe something in project.cc).
-      auto basename = [](const std::string& path) -> std::string {
-        size_t last_index = path.find_last_of('/');
-        if (last_index == std::string::npos)
-          return path;
-        return path.substr(last_index + 1);
-      };
-
-      auto severity_to_string = [](const lsDiagnosticSeverity& severity) {
-        switch (severity) {
-          case lsDiagnosticSeverity::Error:
-            return "error ";
-          case lsDiagnosticSeverity::Warning:
-            return "warning ";
-          case lsDiagnosticSeverity::Information:
-            return "information ";
-          case lsDiagnosticSeverity::Hint:
-            return "hint ";
+          // objective-c tests are often not updated right away. do not bring
+          // down
+          // CI if they fail.
+          if (!enable_update)
+            is_fail_allowed = true;
         }
-        assert(false && "not reached");
-        return "";
-      };
 
-      // Get output from index operation.
-      IndexFile* db = FindDbForPathEnding(expected_path, dbs);
-      assert(db);
-      if (!db->diagnostics_.empty()) {
-        std::cout << "For " << path << std::endl;
-        for (const lsDiagnostic& diagnostic : db->diagnostics_) {
-          std::cout << "  ";
-          if (diagnostic.severity)
-            std::cout << severity_to_string(*diagnostic.severity);
-          std::cout << basename(db->path) << ":"
-                    << diagnostic.range.start.ToString() << "-"
-                    << diagnostic.range.end.ToString() << ": "
-                    << diagnostic.message << std::endl;
+        if (path.find(filter_path) == std::string::npos)
+          return;
+
+        if (!filter_path.empty())
+          printf("Running %s\n", path.c_str());
+
+        // Parse expected output from the test, parse it into JSON document.
+        std::vector<std::string> lines_with_endings;
+        {
+          std::ifstream fin(path);
+          for (std::string line; std::getline(fin, line);)
+            lines_with_endings.push_back(line);
         }
-      }
-      std::string actual_output = "{}";
-      if (db) {
-        VerifySerializeToFrom(db);
-        actual_output = db->ToString();
-      }
-      actual_output = text_replacer.Apply(actual_output);
+        TextReplacer text_replacer;
+        std::vector<std::string> flags;
+        std::unordered_map<std::string, std::string> all_expected_output;
+        ParseTestExpectation(path, lines_with_endings, &text_replacer, &flags,
+                             &all_expected_output);
 
-      // Compare output via rapidjson::Document to ignore any formatting
-      // differences.
-      rapidjson::Document actual;
-      actual.Parse(actual_output.c_str());
-      rapidjson::Document expected;
-      expected.Parse(expected_output.c_str());
+        // Build flags.
+        if (!AnyStartsWith(flags, "-x"))
+          flags.push_back("-xc++");
+        flags.push_back("-resource-dir=" + GetDefaultResourceDirectory());
+        flags.push_back(path);
 
-      if (actual == expected) {
-        // std::cout << "[PASSED] " << path << std::endl;
-      } else {
-        if (!is_fail_allowed)
-          success = false;
-        DiffDocuments(path, expected_path, expected, actual);
-        std::cout << std::endl;
-        std::cout << std::endl;
-        if (enable_update) {
-          std::cout
-              << "[Enter to continue - type u to update test, a to update all]";
-          char c = 'u';
-          if (!update_all) {
-            c = getchar();
-            getchar();
+        // Run test.
+        g_config = std::make_unique<Config>();
+        FileConsumerSharedState file_consumer_shared;
+        PerformanceImportFile perf;
+        auto dbs = Parse(&file_consumer_shared, path, flags, {}, &perf, &index,
+                         false /*dump_ast*/);
+
+        for (const auto& entry : all_expected_output) {
+          const std::string& expected_path = entry.first;
+          std::string expected_output = text_replacer.Apply(entry.second);
+
+          // FIXME: promote to utils, find and remove duplicates (ie,
+          // ccls_call_tree.cc, maybe something in project.cc).
+          auto basename = [](const std::string& path) -> std::string {
+            size_t last_index = path.find_last_of('/');
+            if (last_index == std::string::npos)
+              return path;
+            return path.substr(last_index + 1);
+          };
+
+          // Get output from index operation.
+          IndexFile* db = FindDbForPathEnding(expected_path, dbs);
+          assert(db);
+          if (!db->diagnostics_.empty()) {
+            printf("For %s\n", path.c_str());
+            for (const lsDiagnostic& diagnostic : db->diagnostics_) {
+              printf("  ");
+              if (diagnostic.severity)
+                switch (*diagnostic.severity) {
+                case lsDiagnosticSeverity::Error:
+                  printf("error ");
+                  break;
+                case lsDiagnosticSeverity::Warning:
+                  printf("warning ");
+                  break;
+                case lsDiagnosticSeverity::Information:
+                  printf("information ");
+                  break;
+                case lsDiagnosticSeverity::Hint:
+                  printf("hint ");
+                  break;
+                }
+              printf("%s:%s-%s:%s\n", basename(db->path).c_str(),
+                     diagnostic.range.start.ToString().c_str(),
+                     diagnostic.range.end.ToString().c_str(),
+                     diagnostic.message.c_str());
+            }
           }
+          std::string actual_output = "{}";
+          if (db) {
+            VerifySerializeToFrom(db);
+            actual_output = db->ToString();
+          }
+          actual_output = text_replacer.Apply(actual_output);
 
-          if (c == 'a')
-            update_all = true;
+          // Compare output via rapidjson::Document to ignore any formatting
+          // differences.
+          rapidjson::Document actual;
+          actual.Parse(actual_output.c_str());
+          rapidjson::Document expected;
+          expected.Parse(expected_output.c_str());
 
-          if (update_all || c == 'u') {
-            // Note: we use |entry.second| instead of |expected_output| because
-            // |expected_output| has had text replacements applied.
-            UpdateTestExpectation(path, entry.second, ToString(actual) + "\n");
+          if (actual == expected) {
+            // std::cout << "[PASSED] " << path << std::endl;
+          } else {
+            if (!is_fail_allowed)
+              success = false;
+            DiffDocuments(path, expected_path, expected, actual);
+            puts("\n");
+            if (enable_update) {
+              printf(
+                  "[Enter to continue - type u to update test, a to update "
+                  "all]");
+              char c = 'u';
+              if (!update_all) {
+                c = getchar();
+                getchar();
+              }
+
+              if (c == 'a')
+                update_all = true;
+
+              if (update_all || c == 'u') {
+                // Note: we use |entry.second| instead of |expected_output|
+                // because
+                // |expected_output| has had text replacements applied.
+                UpdateTestExpectation(path, entry.second,
+                                      ToString(actual) + "\n");
+              }
+            }
           }
         }
-      }
-    }
-  }
+      });
 
   return success;
 }
diff --git a/src/utils.cc b/src/utils.cc
index b993c8ef..eb8fb6a3 100644
--- a/src/utils.cc
+++ b/src/utils.cc
@@ -1,6 +1,5 @@
 #include "utils.h"
 
-#include "filesystem.hh"
 #include "platform.h"
 
 #include <doctest/doctest.h>
@@ -12,12 +11,7 @@
 #include <errno.h>
 #include <string.h>
 #include <algorithm>
-#include <fstream>
 #include <functional>
-#include <queue>
-#include <sstream>
-#include <string>
-#include <thread>
 #include <unordered_map>
 using namespace std::placeholders;
 
@@ -83,26 +77,6 @@ bool FindAnyPartial(const std::string& value,
                      });
 }
 
-std::string GetDirName(std::string path) {
-  if (path.size() && path.back() == '/')
-    path.pop_back();
-  size_t last_slash = path.find_last_of('/');
-  if (last_slash == std::string::npos)
-    return ".";
-  if (last_slash == 0)
-    return "/";
-  return path.substr(0, last_slash);
-}
-
-std::string GetBaseName(const std::string& path) {
-  return fs::path(path).filename();
-}
-
-std::string StripFileType(const std::string& path) {
-  fs::path p(path);
-  return p.parent_path() / p.stem();
-}
-
 std::vector<std::string> SplitString(const std::string& str,
                                      const std::string& delimiter) {
   // http://stackoverflow.com/a/13172514
@@ -132,54 +106,6 @@ std::string LowerPathIfInsensitive(const std::string& path) {
 #endif
 }
 
-static void GetFilesInFolderHelper(
-    std::string folder,
-    bool recursive,
-    std::string output_prefix,
-    const std::function<void(const std::string&)>& handler) {
-  std::queue<std::pair<fs::path, fs::path>> q;
-  q.emplace(fs::path(folder), fs::path(output_prefix));
-  while (!q.empty()) {
-    for (auto it = fs::directory_iterator(q.front().first); it != fs::directory_iterator(); ++it) {
-      auto path = it->path();
-      std::string filename = path.filename();
-      if (filename[0] != '.' || filename == ".ccls") {
-        fs::file_status status = it->symlink_status();
-        if (fs::is_regular_file(status))
-          handler(q.front().second / filename);
-        else if (fs::is_directory(status) || fs::is_symlink(status)) {
-          if (recursive) {
-            std::string child_dir = q.front().second / filename;
-            if (fs::is_directory(status))
-              q.push(make_pair(path, child_dir));
-          }
-        }
-      }
-    }
-    q.pop();
-  }
-}
-
-std::vector<std::string> GetFilesInFolder(std::string folder,
-                                          bool recursive,
-                                          bool add_folder_to_path) {
-  EnsureEndsInSlash(folder);
-  std::vector<std::string> result;
-  GetFilesInFolderHelper(
-      folder, recursive, add_folder_to_path ? folder : "",
-      [&result](const std::string& path) { result.push_back(path); });
-  return result;
-}
-
-void GetFilesInFolder(std::string folder,
-                      bool recursive,
-                      bool add_folder_to_path,
-                      const std::function<void(const std::string&)>& handler) {
-  EnsureEndsInSlash(folder);
-  GetFilesInFolderHelper(folder, recursive, add_folder_to_path ? folder : "",
-                         handler);
-}
-
 void EnsureEndsInSlash(std::string& path) {
   if (path.empty() || path[path.size() - 1] != '/')
     path += '/';
@@ -195,10 +121,6 @@ std::string EscapeFileName(std::string path) {
   return path;
 }
 
-bool FileExists(const std::string& filename) {
-  return fs::exists(filename);
-}
-
 std::optional<std::string> ReadContent(const std::string& filename) {
   LOG_S(INFO) << "Reading " << filename;
   char buf[4096];
@@ -211,41 +133,6 @@ std::optional<std::string> ReadContent(const std::string& filename) {
   return ret;
 }
 
-std::vector<std::string> ReadFileLines(std::string filename) {
-  std::vector<std::string> result;
-  std::ifstream fin(filename);
-  for (std::string line; std::getline(fin, line);)
-    result.push_back(line);
-  return result;
-}
-
-std::vector<std::string> ToLines(const std::string& content) {
-  std::vector<std::string> result;
-  std::istringstream lines(content);
-  std::string line;
-  while (getline(lines, line))
-    result.push_back(line);
-  return result;
-}
-
-std::string TextReplacer::Apply(const std::string& content) {
-  std::string result = content;
-
-  for (const Replacement& replacement : replacements) {
-    while (true) {
-      size_t idx = result.find(replacement.from);
-      if (idx == std::string::npos)
-        break;
-
-      result.replace(result.begin() + idx,
-                     result.begin() + idx + replacement.from.size(),
-                     replacement.to);
-    }
-  }
-
-  return result;
-}
-
 void WriteToFile(const std::string& filename, const std::string& content) {
   FILE* f = fopen(filename.c_str(), "wb");
   if (!f || fwrite(content.c_str(), content.size(), 1, f) != 1) {
@@ -278,19 +165,3 @@ std::string GetDefaultResourceDirectory() {
 
   return NormalizePath(result);
 }
-
-void StartThread(const std::string& thread_name, std::function<void()> entry) {
-  new std::thread([thread_name, entry]() {
-    SetCurrentThreadName(thread_name);
-    entry();
-  });
-}
-
-TEST_SUITE("StripFileType") {
-  TEST_CASE("all") {
-    REQUIRE(StripFileType("") == "");
-    REQUIRE(StripFileType("bar") == "bar");
-    REQUIRE(StripFileType("bar.cc") == "bar");
-    REQUIRE(StripFileType("foo/bar.cc") == "foo/bar");
-  }
-}
diff --git a/src/utils.h b/src/utils.h
index baba2774..82755e71 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -4,7 +4,6 @@
 #include <string_view>
 
 #include <algorithm>
-#include <functional>
 #include <iterator>
 #include <memory>
 #include <string>
@@ -23,13 +22,6 @@ bool StartsWithAny(std::string_view s, const std::vector<std::string>& ps);
 bool EndsWithAny(std::string_view s, const std::vector<std::string>& ss);
 bool FindAnyPartial(const std::string& value,
                     const std::vector<std::string>& values);
-// Returns the dirname of |path|, i.e. "foo/bar.cc" => "foo", "foo" => ".",
-// "/foo" => "/".
-std::string GetDirName(std::string path);
-// Returns the basename of |path|, ie, "foo/bar.cc" => "bar.cc".
-std::string GetBaseName(const std::string& path);
-// Returns |path| without the filetype, ie, "foo/bar.cc" => "foo/bar".
-std::string StripFileType(const std::string& path);
 
 std::vector<std::string> SplitString(const std::string& str,
                                      const std::string& delimiter);
@@ -62,15 +54,6 @@ bool ContainsValue(const TCollection& collection, const TValue& value) {
   return collection.find(value) != collection.end();
 }
 
-// Finds all files in the given folder. This is recursive.
-std::vector<std::string> GetFilesInFolder(std::string folder,
-                                          bool recursive,
-                                          bool add_folder_to_path);
-void GetFilesInFolder(std::string folder,
-                      bool recursive,
-                      bool add_folder_to_path,
-                      const std::function<void(const std::string&)>& handler);
-
 // Ensures that |path| ends in a slash.
 void EnsureEndsInSlash(std::string& path);
 
@@ -78,22 +61,7 @@ void EnsureEndsInSlash(std::string& path);
 // e.g. foo/bar.c => foo_bar.c
 std::string EscapeFileName(std::string path);
 
-// FIXME: Move ReadContent into ICacheManager?
-bool FileExists(const std::string& filename);
 std::optional<std::string> ReadContent(const std::string& filename);
-std::vector<std::string> ReadFileLines(std::string filename);
-std::vector<std::string> ToLines(const std::string& content);
-
-struct TextReplacer {
-  struct Replacement {
-    std::string from;
-    std::string to;
-  };
-
-  std::vector<Replacement> replacements;
-
-  std::string Apply(const std::string& content);
-};
 
 void WriteToFile(const std::string& filename, const std::string& content);
 
@@ -149,5 +117,3 @@ inline void hash_combine(std::size_t& seed, const T& v, Rest... rest) {
   }
 
 std::string GetDefaultResourceDirectory();
-
-void StartThread(const std::string& thread_name, std::function<void()> entry);
diff --git a/src/working_files.cc b/src/working_files.cc
index 478a6ff5..cdc5e5ef 100644
--- a/src/working_files.cc
+++ b/src/working_files.cc
@@ -9,6 +9,7 @@
 #include <algorithm>
 #include <climits>
 #include <numeric>
+#include <sstream>
 
 namespace {
 
@@ -38,6 +39,15 @@ lsPosition GetPositionForOffset(const std::string& content, int offset) {
   return result;
 }
 
+std::vector<std::string> ToLines(const std::string& content) {
+  std::vector<std::string> result;
+  std::istringstream lines(content);
+  std::string line;
+  while (getline(lines, line))
+    result.push_back(line);
+  return result;
+}
+
 // Computes the edit distance of strings [a,a+la) and [b,b+lb) with Eugene W.
 // Myers' O(ND) diff algorithm.
 // Costs: insertion=1, deletion=1, no substitution.