LibCore: Replace the ArgsParser option argument setting with an enum

Replacement conditions for `requires_argument` have been chosen based
on what would be most convenient for implementing an eventual optional
argument mode.

Userland/Utilities/du.cpp

@@ -59,7 +59,7 @@ ErrorOr<void> parse_args(Main::Arguments arguments, Vector<String>& files, DuOpt
     Vector<StringView> files_to_process;
 
     Core::ArgsParser::Option time_option {
-        true,
+        Core::ArgsParser::OptionArgumentMode::Required,
         "Show time of type time-type of any file in the directory, or any of its subdirectories. "
         "Available choices: mtime, modification, ctime, status, use, atime, access",
         "time",

Userland/Utilities/grep.cpp

@@ -59,7 +59,7 @@ ErrorOr<int> serenity_main(Main::Arguments args)
     args_parser.add_option(recursive, "Recursively scan files", "recursive", 'r');
     args_parser.add_option(use_ere, "Extended regular expressions", "extended-regexp", 'E');
     args_parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Pattern",
         .long_name = "regexp",
         .short_name = 'e',
@@ -75,7 +75,7 @@ ErrorOr<int> serenity_main(Main::Arguments args)
     args_parser.add_option(quiet_mode, "Do not write anything to standard output", "quiet", 'q');
     args_parser.add_option(suppress_errors, "Suppress error messages for nonexistent or unreadable files", "no-messages", 's');
     args_parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Action to take for binary files ([binary], text, skip)",
         .long_name = "binary-mode",
         .accept_value = [&](auto* str) {
@@ -91,7 +91,7 @@ ErrorOr<int> serenity_main(Main::Arguments args)
         },
     });
     args_parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = false,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::None,
         .help_string = "Treat binary files as text (same as --binary-mode text)",
         .long_name = "text",
         .short_name = 'a',
@@ -101,7 +101,7 @@ ErrorOr<int> serenity_main(Main::Arguments args)
         },
     });
     args_parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = false,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::None,
         .help_string = "Ignore binary files (same as --binary-mode skip)",
         .long_name = nullptr,
         .short_name = 'I',
@@ -111,7 +111,7 @@ ErrorOr<int> serenity_main(Main::Arguments args)
         },
     });
     args_parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "When to use colored output for the matching text ([auto], never, always)",
         .long_name = "color",
         .short_name = 0,

Userland/Utilities/nl.cpp

@@ -30,7 +30,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     Core::ArgsParser args_parser;
 
     Core::ArgsParser::Option number_style_option {
-        true,
+        Core::ArgsParser::OptionArgumentMode::Required,
         "Line numbering style: 't' for non-empty lines, 'a' for all lines, 'n' for no lines",
         "body-numbering",
         'b',

Userland/Utilities/pro.cpp

@@ -164,7 +164,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     args_parser.add_option(data, "(HTTP only) Send the provided data via an HTTP POST request", "data", 'd', "data");
     args_parser.add_option(should_follow_url, "(HTTP only) Follow the Location header if a 3xx status is encountered", "follow", 'l');
     args_parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Add a header entry to the request",
         .long_name = "header",
         .short_name = 'H',

Userland/Utilities/profile.cpp

@@ -35,7 +35,8 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     args_parser.add_option(wait, "Enable profiling and wait for user input to disable.", nullptr, 'w');
     args_parser.add_option(cmd_argument, "Command", nullptr, 'c', "command");
     args_parser.add_option(Core::ArgsParser::Option {
-        true, "Enable tracking specific event type", nullptr, 't', "event_type",
+        Core::ArgsParser::OptionArgumentMode::Required,
+        "Enable tracking specific event type", nullptr, 't', "event_type",
         [&](String event_type) {
             seen_event_type_arg = true;
             if (event_type == "sample")

Userland/Utilities/run-tests.cpp

@@ -322,7 +322,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
 
     Core::ArgsParser args_parser;
     args_parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Show progress with OSC 9 (true, false)",
         .long_name = "show-progress",
         .short_name = 'p',

Userland/Utilities/test-unveil.cpp

@@ -20,7 +20,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     parser.add_option(permissions, "Apply these permissions going forward", "permissions", 'p', "unveil-permissions");
     parser.add_option(should_sleep, "Sleep after processing all arguments", "sleep", 's');
     parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Add a path to the unveil list",
         .long_name = "unveil",
         .short_name = 'u',
@@ -37,7 +37,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
             return true;
         } });
     parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = false,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::None,
         .help_string = "Lock the veil",
         .long_name = "lock",
         .short_name = 'l',

Userland/Utilities/top.cpp

@@ -138,7 +138,7 @@ static struct winsize g_window_size;
 static void parse_args(Main::Arguments arguments, TopOption& top_option)
 {
     Core::ArgsParser::Option sort_by_option {
-        true,
+        Core::ArgsParser::OptionArgumentMode::Required,
         "Sort by field [pid, tid, pri, user, state, virt, phys, cpu, name]",
         "sort-by",
         's',

Userland/Utilities/wasm.cpp

@@ -288,7 +288,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     parser.add_option(export_all_imports, "Export noop functions corresponding to imports", "export-noop", 0);
     parser.add_option(shell_mode, "Launch a REPL in the module's context (implies -i)", "shell", 's');
     parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Extra modules to link with, use to resolve imports",
         .long_name = "link",
         .short_name = 'l',
@@ -302,7 +302,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
         },
     });
     parser.add_option(Core::ArgsParser::Option {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Supply arguments to the function (default=0) (expects u64, casts to required type)",
         .long_name = "arg",
         .short_name = 0,

Userland/Utilities/watch.cpp

@@ -121,7 +121,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     args_parser.add_option(flag_noheader, "Turn off the header describing the command and interval", "no-title", 't');
     args_parser.add_option(flag_beep_on_fail, "Beep if the command has a non-zero exit code", "beep", 'b');
     Core::ArgsParser::Option file_arg {
-        .requires_argument = true,
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Required,
         .help_string = "Run command whenever this file changes. Can be used multiple times.",
         .long_name = "file",
         .short_name = 'f',