Add support for hidden commands, that will not show on completion

README.asciidoc

@@ -668,6 +668,7 @@ def can also takes some flags:
                         completion candidate per line.
  * +-allow-override+: allow the new command to replace an exisiting one
                       with the same name.
+ * +-hidden+: do not show the command in command name completions
 
 Using shell expansion permits to define complex commands or to access
 kakoune state:

src/command_manager.cc

@@ -18,17 +18,19 @@ bool CommandManager::command_defined(const String& command_name) const
 
 void CommandManager::register_command(String command_name,
                                       Command command,
+                                      CommandFlags flags,
                                       CommandCompleter completer)
 {
-    m_commands[command_name] = { std::move(command), std::move(completer) };
+    m_commands[command_name] = { std::move(command), flags, std::move(completer) };
 }
 
 void CommandManager::register_commands(memoryview<String> command_names,
                                        Command command,
+                                       CommandFlags flags,
                                        CommandCompleter completer)
 {
     for (auto command_name : command_names)
-        m_commands[command_name] = { command, completer };
+        m_commands[command_name] = { command, flags, completer };
 }
 
 struct parse_error : runtime_error
@@ -337,6 +339,8 @@ Completions CommandManager::complete(const Context& context, CompletionFlags fla
 
         for (auto& command : m_commands)
         {
+            if (command.second.flags & CommandFlags::Hidden)
+                continue;
             if ( prefix_match(command.first, prefix))
                 result.candidates.push_back(command.first);
         }

src/command_manager.hh

@@ -21,6 +21,19 @@ using CommandCompleter = std::function<CandidateList (const Context& context,
                                                       CompletionFlags,
                                                       CommandParameters,
                                                       size_t, ByteCount)>;
+enum class CommandFlags
+{
+    None   = 0,
+    Hidden = 1,
+};
+constexpr CommandFlags operator|(CommandFlags lhs, CommandFlags rhs)
+{
+    return (CommandFlags)((int)lhs | (int)rhs);
+}
+constexpr bool operator&(CommandFlags lhs, CommandFlags rhs)
+{
+    return (bool)((int)lhs & (int)rhs);
+}
 
 class PerArgumentCommandCompleter
 {
@@ -55,12 +68,12 @@ public:
 
     bool command_defined(const String& command_name) const;
 
-    void register_command(String command_name,
+    void register_command(String command_name, Command command,
-                          Command command,
+                          CommandFlags flags = CommandFlags::None,
                           CommandCompleter completer = CommandCompleter());
 
-    void register_commands(memoryview<String> command_names,
+    void register_commands(memoryview<String> command_names, Command command,
-                           Command command,
+                           CommandFlags flags = CommandFlags::None,
                            CommandCompleter completer = CommandCompleter());
 
 private:
@@ -69,6 +82,7 @@ private:
     struct CommandDescriptor
     {
         Command command;
+        CommandFlags flags;
         CommandCompleter completer;
     };
     std::unordered_map<String, CommandDescriptor> m_commands;

src/commands.cc

@@ -333,6 +333,7 @@ void define_command(CommandParameters params, Context& context)
                               { "shell-params", false },
                               { "allow-override", false },
                               { "file-completion", false },
+                              { "hidden", false },
                               { "shell-completion", true } },
                              ParametersParser::Flags::None,
                              2, 2);
@@ -344,6 +345,10 @@ void define_command(CommandParameters params, Context& context)
         not parser.has_option("allow-override"))
         throw runtime_error("command '" + cmd_name + "' already defined");
 
+    CommandFlags flags = CommandFlags::None;
+    if (parser.has_option("hidden"))
+        flags = CommandFlags::Hidden;
+
     String commands = parser[1];
     Command cmd;
     if (parser.has_option("env-params"))
@@ -397,7 +402,7 @@ void define_command(CommandParameters params, Context& context)
             return split(output, '\n');
         };
     }
-    CommandManager::instance().register_command(cmd_name, cmd, completer);
+    CommandManager::instance().register_command(cmd_name, cmd, flags, completer);
 }
 
 void echo_message(CommandParameters params, Context& context)
@@ -809,9 +814,9 @@ void register_commands()
          [](const Context& context, CompletionFlags flags, const String& prefix, ByteCount cursor_pos)
          { return complete_filename(prefix, context.options()["ignored_files"].get<Regex>(), cursor_pos); }
     });
-    cm.register_commands({ "e", "edit" }, edit<false>, filename_completer);
+    cm.register_commands({ "e", "edit" }, edit<false>, CommandFlags::None, filename_completer);
-    cm.register_commands({ "e!", "edit!" }, edit<true>, filename_completer);
+    cm.register_commands({ "e!", "edit!" }, edit<true>, CommandFlags::None, filename_completer);
-    cm.register_commands({ "w", "write" }, write_buffer, filename_completer);
+    cm.register_commands({ "w", "write" }, write_buffer, CommandFlags::None, filename_completer);
     cm.register_commands({ "wa", "writeall" }, write_all_buffers);
     cm.register_commands({ "q", "quit" }, quit<false>);
     cm.register_commands({ "q!", "quit!" }, quit<true>);
@@ -822,19 +827,19 @@ void register_commands()
         [](const Context& context, CompletionFlags flags, const String& prefix, ByteCount cursor_pos)
         { return BufferManager::instance().complete_buffername(prefix, cursor_pos); }
     });
-    cm.register_commands({ "b", "buffer" }, show_buffer, buffer_completer);
+    cm.register_commands({ "b", "buffer" }, show_buffer, CommandFlags::None, buffer_completer);
-    cm.register_commands({ "db", "delbuf" }, delete_buffer<false>, buffer_completer);
+    cm.register_commands({ "db", "delbuf" }, delete_buffer<false>, CommandFlags::None, buffer_completer);
-    cm.register_commands({ "db!", "delbuf!" }, delete_buffer<true>, buffer_completer);
+    cm.register_commands({ "db!", "delbuf!" }, delete_buffer<true>, CommandFlags::None, buffer_completer);
     cm.register_commands({"nb", "namebuf"}, set_buffer_name);
 
     auto get_highlighters = [](const Context& c) -> HighlighterGroup& { return c.window().highlighters(); };
-    cm.register_commands({ "ah", "addhl" }, add_highlighter, group_add_completer<HighlighterRegistry>(get_highlighters));
+    cm.register_commands({ "ah", "addhl" }, add_highlighter, CommandFlags::None, group_add_completer<HighlighterRegistry>(get_highlighters));
-    cm.register_commands({ "rh", "rmhl" }, rm_highlighter, group_rm_completer(get_highlighters));
+    cm.register_commands({ "rh", "rmhl" }, rm_highlighter, CommandFlags::None, group_rm_completer(get_highlighters));
 
     cm.register_command("hook", add_hook);
     cm.register_command("rmhooks", rm_hooks);
 
-    cm.register_command("source", exec_commands_in_file, filename_completer);
+    cm.register_command("source", exec_commands_in_file, CommandFlags::None, filename_completer);
 
     cm.register_command("exec", exec_string);
     cm.register_command("eval", eval_string);
@@ -849,7 +854,7 @@ void register_commands()
     cm.register_command("echo", echo_message);
     cm.register_command("debug", write_debug_message);
 
-    cm.register_command("set", set_option,
+    cm.register_command("set", set_option, CommandFlags::None,
                         [](const Context& context, CompletionFlags, CommandParameters params, size_t token_to_complete, ByteCount pos_in_token)
                         {
                             if (token_to_complete == 0)
@@ -873,7 +878,7 @@ void register_commands()
     cm.register_commands({"ca", "colalias"}, define_color_alias);
     cm.register_commands({"nc", "nameclient"}, set_client_name);
 
-    cm.register_command("cd", change_working_directory, filename_completer);
+    cm.register_command("cd", change_working_directory, CommandFlags::None, filename_completer);
     cm.register_command("map", map_key);
 }
 }