Initial clang-tidy configuration (#1253)

* clang-tidy: misc

* added consts, fixed a initialization to pass clang-tidy

# Conflicts:
#	source/reflect.h

* added consts, masked a lint in reflect.h2 to pass clang-tidy

* clang-tidy: modernize

* clang-tidy: performance

* replace const with constexpr in initialization of stable version strings

* apply suggested changes

* Style: Use `i8` and `u8` aliases

* Update cppfront.cpp

Signed-off-by: Herb Sutter <[email protected]>

---------

Signed-off-by: Herb Sutter <[email protected]>
Co-authored-by: Herb Sutter <[email protected]>

Author: farmerpiki

.clang-tidy

@@ -0,0 +1 @@
+Checks: 'performance-*, modernize-*, misc-*, -misc-definitions-in-headers, -misc-non-private-member-variables-in-classes, -misc-no-recursion, -misc-include-cleaner, -misc-use-anonymous-namespace, -modernize-use-trailing-return-type, -modernize-use-nodiscard, -modernize-use-emplace, -modernize-loop-convert, -modernize-pass-by-value, -modernize-use-equals-delete, -modernize-use-equals-default, -modernize-use-override, -modernize-avoid-c-arrays, -modernize-raw-string-literal, -modernize-concat-nested-namespaces, -performance-inefficient-string-concatenation'

include/cpp2util.h

@@ -1859,12 +1859,12 @@ constexpr auto is_narrowing_v =
     // [dcl.init.list] 7.1
     (std::is_floating_point_v<From> && std::is_integral_v<To>) ||
     // [dcl.init.list] 7.2
-    (std::is_floating_point_v<From> && std::is_floating_point_v<To> && sizeof(From) > sizeof(To)) ||
+    (std::is_floating_point_v<From> && std::is_floating_point_v<To> && sizeof(From) > sizeof(To)) || // NOLINT(misc-redundant-expression)
     // [dcl.init.list] 7.3
     (std::is_integral_v<From> && std::is_floating_point_v<To>) ||
     (std::is_enum_v<From> && std::is_floating_point_v<To>) ||
     // [dcl.init.list] 7.4
-    (std::is_integral_v<From> && std::is_integral_v<To> && sizeof(From) > sizeof(To)) ||
+    (std::is_integral_v<From> && std::is_integral_v<To> && sizeof(From) > sizeof(To)) || // NOLINT(misc-redundant-expression)
     (std::is_enum_v<From> && std::is_integral_v<To> && sizeof(From) > sizeof(To)) ||
     // [dcl.init.list] 7.5
     (std::is_pointer_v<From> && std::is_same_v<To, bool>)

source/common.h

@@ -65,7 +65,7 @@ struct source_line
 {
     std::string text;
 
-    enum class category { empty, preprocessor, comment, import, cpp1, cpp2, rawstring };
+    enum class category : u8 { empty, preprocessor, comment, import, cpp1, cpp2, rawstring };
     category cat;
 
     bool all_tokens_are_densely_spaced = true; // to be overridden in lexing if they're not
@@ -128,7 +128,7 @@ struct source_position
 
 struct comment
 {
-    enum class comment_kind { line_comment = 0, stream_comment };
+    enum class comment_kind : u8 { line_comment = 0, stream_comment };
 
     comment_kind    kind;
     source_position start;
@@ -141,7 +141,7 @@ struct comment
 struct string_parts {
     struct cpp_code   { std::string text; };
     struct raw_string { std::string text; };
-    enum adds_sequences { no_ends = 0, on_the_beginning = 1, on_the_end = 2, on_both_ends = 3 };
+    enum adds_sequences : u8 { no_ends = 0, on_the_beginning = 1, on_the_end = 2, on_both_ends = 3 };
 
     string_parts(const std::string& beginseq,
                  const std::string& endseq,
@@ -892,8 +892,8 @@ class cmdline_processor
         -> void
     {
         help_requested = true;
-        std::string_view a = __DATE__;
-        std::string_view b = __TIME__;
+        constexpr std::string_view a = __DATE__;
+        constexpr std::string_view b = __TIME__;
         std::unordered_map<std::string_view, char> m = { {"Jan",'1'}, {"Feb",'2'}, {"Mar",'3'}, {"Apr",'4'}, {"May",'5'}, {"Jun",'6'}, {"Jul",'7'}, {"Aug",'8'}, {"Sep",'9'}, {"Oct",'A'}, {"Nov",'B'}, {"Dec",'C'} };
 
         auto stamp = std::to_string(atoi(&a[9])-15);

source/cppfront.cpp

@@ -72,7 +72,7 @@ auto main(
             }
             else {
                 std::cerr << arg.text << " - ambiguous compiler flag name, did you mean one of these?\n";
-                for (auto a : ambiguous) {
+                for (auto const& a : ambiguous) {
                     std::cerr << "  " << arg.text.front() << a << "\n";
                 }
             }
@@ -137,7 +137,7 @@ auto main(
                     auto total_time = print_with_thousands(t.elapsed().count());
                     std::cout << "\n   Time  " << total_time << " ms";
 
-                    std::multimap< long long, std::string_view, std::greater<long long> > sorted_timers;
+                    std::multimap< long long, std::string_view, std::greater<> > sorted_timers;
                     for (auto [name, t] : timers) {
                         sorted_timers.insert({t.elapsed().count(), name});
                     }

source/io.h

@@ -504,7 +504,7 @@ class braces_tracker
 //
 //  line    current line being processed
 //
-enum class preprocessor_conditional {
+enum class preprocessor_conditional : u8 {
     none = 0, pre_if, pre_else, pre_endif
 };
 auto starts_with_preprocessor_if_else_endif(
@@ -635,7 +635,7 @@ auto process_cpp_line(
                         i+=2;
                         if (i < ssize(line) - 1)
                         {
-                            if (auto paren_pos = line.find("(", i);
+                            if (auto paren_pos = line.find('(', i);
                                 paren_pos != line.npos
                                 )
                             {
@@ -841,7 +841,7 @@ class source
     static const int max_line_len = 90'000;
         //  do not reduce this - I encountered an 80,556-char
         //  line in real world code during testing
-    char buf[max_line_len];
+    char buf[max_line_len] {0};
 
 public:
     //-----------------------------------------------------------------------
@@ -854,7 +854,6 @@ class source
     )
         : errors{ errors_ }
         , lines( 1 )        // extra blank to avoid off-by-one everywhere
-        , buf{0}
     {
     }
 

source/lex.h

@@ -33,7 +33,7 @@ namespace cpp2 {
 //-----------------------------------------------------------------------
 //
 
-enum class lexeme : std::int8_t {
+enum class lexeme : i8 {
     SlashEq,
     Slash,
     LeftShiftEq,
@@ -1496,7 +1496,7 @@ auto lex_line(
                     auto R_pos = i + 1;
                     auto seq_pos = i + 3;
 
-                    if (auto paren_pos = line.find("(", seq_pos); paren_pos != line.npos) {
+                    if (auto paren_pos = line.find('(', seq_pos); paren_pos != line.npos) {
                         auto opening_seq = line.substr(i, paren_pos - i + 1);
                         auto closing_seq = ")"+line.substr(seq_pos, paren_pos-seq_pos)+"\"";
 
@@ -1717,7 +1717,7 @@ auto lex_line(
                     if (peek(j-2) == 'R') {
                         auto seq_pos = i + j;
 
-                        if (auto paren_pos = line.find("(", seq_pos); paren_pos != line.npos) {
+                        if (auto paren_pos = line.find('(', seq_pos); paren_pos != line.npos) {
                             auto opening_seq = line.substr(i, paren_pos - i + 1);
                             auto closing_seq = ")"+line.substr(seq_pos, paren_pos-seq_pos)+"\"";
 

source/parse.h

@@ -130,7 +130,7 @@ struct template_argument;
 
 struct primary_expression_node
 {
-    enum active { empty=0, identifier, expression_list, id_expression, declaration, inspect, literal };
+    enum active : u8 { empty=0, identifier, expression_list, id_expression, declaration, inspect, literal };
     std::variant<
         std::monostate,
         token const*,
@@ -669,7 +669,7 @@ auto binary_expression_node<Name, Term>::is_standalone_expression() const
 }
 
 
-enum class passing_style { in=0, copy, inout, out, move, forward, invalid };
+enum class passing_style : u8 { in=0, copy, inout, out, move, forward, invalid };
 auto to_passing_style(token const& t) -> passing_style {
     if (t.type() == lexeme::Identifier) {
         if (t == "in"     ) { return passing_style::in; }
@@ -1179,7 +1179,7 @@ struct template_args_tag { };
 
 struct template_argument
 {
-    enum active { empty=0, expression, type_id };
+    enum active : u8 { empty=0, expression, type_id };
     source_position comma;
     std::variant<
         std::monostate,
@@ -1365,7 +1365,7 @@ struct type_id_node
     int                       dereference_cnt           = {};
     token const*              suspicious_initialization = {};
 
-    enum active { empty=0, qualified, unqualified, function, keyword };
+    enum active : u8 { empty=0, qualified, unqualified, function, keyword };
     std::variant<
         std::monostate,
         std::unique_ptr<qualified_id_node>,
@@ -1666,7 +1666,7 @@ struct id_expression_node
 {
     source_position pos;
 
-    enum active { empty=0, qualified, unqualified };
+    enum active : u8 { empty=0, qualified, unqualified };
     std::variant<
         std::monostate,
         std::unique_ptr<qualified_id_node>,
@@ -2153,7 +2153,7 @@ struct statement_node
     // type(s) used in a std::unique_ptr as a member
     ~statement_node();
 
-    enum active { expression=0, compound, selection, declaration, return_, iteration, using_, contract, inspect, jump };
+    enum active : u8 { expression=0, compound, selection, declaration, return_, iteration, using_, contract, inspect, jump };
     std::variant<
         std::unique_ptr<expression_statement_node>,
         std::unique_ptr<compound_statement_node>,
@@ -2281,7 +2281,7 @@ struct parameter_declaration_node
     passing_style   pass    = passing_style::in;
     int             ordinal = 1;
 
-    enum class modifier { none=0, implicit, virtual_, override_, final_ };
+    enum class modifier : u8 { none=0, implicit, virtual_, override_, final_ };
     modifier mod = modifier::none;
 
     std::unique_ptr<declaration_node> declaration;
@@ -2483,7 +2483,7 @@ struct function_type_node
         passing_style pass = passing_style::move;
     };
 
-    enum active { empty = 0, id, list };
+    enum active : u8 { empty = 0, id, list };
     std::variant<
         std::monostate,
         single_type_id,
@@ -2862,7 +2862,7 @@ struct alias_node
     token const* type = {};
     std::unique_ptr<type_id_node> type_id;   // for objects
 
-    enum active : std::uint8_t { a_type, a_namespace, an_object };
+    enum active : u8 { a_type, a_namespace, an_object };
     std::variant<
         std::unique_ptr<type_id_node>,
         std::unique_ptr<id_expression_node>,
@@ -2903,7 +2903,7 @@ struct alias_node
 };
 
 
-enum class accessibility { default_ = 0, public_, protected_, private_ };
+enum class accessibility : u8 { default_ = 0, public_, protected_, private_ };
 
 auto to_string(accessibility a)
     -> std::string
@@ -2932,7 +2932,7 @@ struct declaration_node
     std::unique_ptr<unqualified_id_node> identifier;
     accessibility                        access = accessibility::default_;
 
-    enum active : std::uint8_t { a_function, an_object, a_type, a_namespace, an_alias };
+    enum active : u8 { a_function, an_object, a_type, a_namespace, an_alias };
     std::variant<
         std::unique_ptr<function_type_node>,
         std::unique_ptr<type_id_node>,
@@ -3353,7 +3353,7 @@ struct declaration_node
     auto parent_is_polymorphic() const -> bool
         { return  parent_declaration && parent_declaration->is_polymorphic(); }
 
-    enum which {
+    enum which : u8 {
         functions = 1,
         objects   = 2,
         types     = 4,
@@ -3421,7 +3421,7 @@ struct declaration_node
     {
         //  Convert the gather_ results to const*
         auto tmp = gather_type_scope_declarations(w);
-        return std::vector<declaration_node const*>(tmp.begin(), tmp.end());
+        return {tmp.begin(), tmp.end()};
     }
 
 
@@ -6105,7 +6105,7 @@ class parser
             //  Remember current position, because we may need to backtrack
             auto start_pos = pos;
 
-            bool inside_initializer = (
+            const bool inside_initializer = (
                 peek(-1) && peek(-1)->type() == lexeme::Assignment
             );
             auto open_paren = &curr();
@@ -8069,7 +8069,7 @@ class parser
     )
         -> std::unique_ptr<compound_statement_node>
     {
-        bool is_braced = curr().type() == lexeme::LeftBrace;
+        const bool is_braced = curr().type() == lexeme::LeftBrace;
         if (
             !is_braced
             && !allow_single_unbraced_statement