[MISC] Allow recursive subcommands

doc/howto/subcommand_parser/index.md

@@ -51,3 +51,10 @@ followed by the keyword `push` which in this case triggers printing the help pag
 That's it. Here is a full example of a subcommand parser you can try and adjust to your needs:
 
 \include doc/howto/subcommand_parser/subcommand_parse.cpp
+
+# Recursive subcommands
+
+If you want to have subcommands with subcommands, you can add subcommands to the sub-parser
+with sharg::parser::add_subcommands():
+
+\include test/snippet/add_subcommands.cpp

include/sharg/parser.hpp

@@ -169,8 +169,6 @@ class parser
      * \param[in] version_updates Notify users about version updates (default sharg::update_notifications::on).
      * \param[in] subcommands A list of subcommands (see \link subcommand_parse subcommand parsing \endlink).
      *
-     * \throws sharg::design_error if the application name contains illegal characters.
-     *
      * The application name must only contain alpha-numeric characters, `_` or `-` ,
      * i.e. the following regex must evaluate to true: `"^[a-zA-Z0-9_-]+$"` .
      *
@@ -185,9 +183,9 @@ class parser
            update_notifications version_updates = update_notifications::on,
            std::vector<std::string> subcommands = {}) :
         version_check_dev_decision{version_updates},
-        subcommands{std::move(subcommands)},
         arguments{arguments}
     {
+        add_subcommands(subcommands);
         info.app_name = app_name;
     }
 
@@ -352,7 +350,7 @@ class parser
      * related code and should be enclosed in a try catch block as the parser may throw.
      *
      * \throws sharg::design_error if this function was already called before.
-     *
+     * \throws sharg::design_error if the application name or subcommands contain illegal characters.
      * \throws sharg::option_declared_multiple_times if an option that is not a list was declared multiple times.
      * \throws sharg::user_input_error if an incorrect argument is given as (positional) option value.
      * \throws sharg::required_option_missing if the user did not provide a required option.
@@ -639,6 +637,27 @@ class parser
 
         operations.push_back(std::move(operation));
     }
+
+    /*!\brief Adds subcommands to the parser.
+     * \param[in] subcommands A list of subcommands.
+     * \details
+     * Adds subcommands to the current parser. The list of subcommands is sorted and duplicates are removed.
+     *
+     * ### Example
+     *
+     * \include test/snippet/add_subcommands.cpp
+     *
+     * \experimentalapi{Experimental since version 1.1.2}
+     */
+    void add_subcommands(std::vector<std::string> const & subcommands)
+    {
+        auto & parser_subcommands = this->subcommands;
+        parser_subcommands.insert(parser_subcommands.end(), subcommands.cbegin(), subcommands.cend());
+
+        std::ranges::sort(parser_subcommands);
+        auto const [first, last] = std::ranges::unique(parser_subcommands);
+        parser_subcommands.erase(first, last);
+    }
     //!\}
 
     /*!\brief Aggregates all parser related meta data (see sharg::parser_meta_data struct).

test/snippet/add_subcommands.cpp

@@ -0,0 +1,65 @@
+// SPDX-FileCopyrightText: 2006-2024 Knut Reinert & Freie Universität Berlin
+// SPDX-FileCopyrightText: 2016-2024 Knut Reinert & MPI für molekulare Genetik
+// SPDX-License-Identifier: CC0-1.0
+
+#include <sharg/all.hpp>
+
+void run(std::vector<std::string> const & arguments)
+{
+    sharg::parser git_parser{"git", arguments, sharg::update_notifications::off, {"pull", "push"}};
+    git_parser.add_subcommands({"remote"});
+    git_parser.parse();
+
+    sharg::parser & sub_parser = git_parser.get_sub_parser();
+
+    if (sub_parser.info.app_name == std::string_view{"git-pull"})
+    {
+        auto & pull_parser = sub_parser;
+        std::string repository{};
+        pull_parser.add_positional_option(repository, sharg::config{});
+        pull_parser.parse();
+    }
+    else if (sub_parser.info.app_name == std::string_view{"git-push"})
+    {
+        auto & push_parser = sub_parser;
+        std::string repository{};
+        push_parser.add_positional_option(repository, sharg::config{});
+        push_parser.parse();
+    }
+    else if (sub_parser.info.app_name == std::string_view{"git-remote"})
+    {
+        auto & remote_parser = sub_parser;
+        remote_parser.add_subcommands({"set-url", "show"});
+        remote_parser.parse();
+
+        sharg::parser & recursive_sub_parser = remote_parser.get_sub_parser();
+
+        if (recursive_sub_parser.info.app_name == std::string_view{"git-remote-set-url"})
+        {
+            auto & set_url_parser = recursive_sub_parser;
+            std::string repository{};
+            set_url_parser.add_positional_option(repository, sharg::config{});
+            set_url_parser.parse();
+        }
+        else if (recursive_sub_parser.info.app_name == std::string_view{"git-remote-show"})
+        {
+            auto & show_parser = recursive_sub_parser;
+            show_parser.parse();
+        }
+    }
+}
+
+int main(int argc, char ** argv)
+{
+    try
+    {
+        run({argv, argv + argc});
+    }
+    catch (sharg::parser_error const & ext)
+    {
+        std::cerr << "[Error] " << ext.what() << '\n';
+        std::exit(-1);
+    }
+
+    return 0;
+}

test/snippet/add_subcommands.out

@@ -0,0 +1,3 @@
+git
+===
+    Try -h or --help for more information.

test/snippet/add_subcommands.out.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2006-2024 Knut Reinert & Freie Universität Berlin
+SPDX-FileCopyrightText: 2016-2024 Knut Reinert & MPI für molekulare Genetik
+SPDX-License-Identifier: CC0-1.0

test/unit/detail/format_cwl_test.cpp

@@ -277,4 +277,74 @@ TEST_F(format_cwl_test, subparser)
         "  - index\n";
     EXPECT_EQ(get_parse_cout_on_exit(sub_parser), expected_short);
 }
+
+TEST_F(format_cwl_test, subsubparser)
+{
+    // Create variables for the arguments
+    int option_value{5};
+    std::string option_value_string{};
+    std::filesystem::path option_value_path{};
+
+    // Create the dummy parser.
+    auto parser = get_subcommand_parser({"index", "show", "--export-help", "cwl"}, {"index"});
+
+    EXPECT_NO_THROW(parser.parse());
+
+    auto & sub_parser = parser.get_sub_parser();
+    ASSERT_EQ(sub_parser.info.app_name, "test_parser-index");
+
+    sub_parser.add_subcommands({"show"});
+    EXPECT_NO_THROW(sub_parser.parse());
+
+    auto & sub_sub_parser = sub_parser.get_sub_parser();
+    sub_sub_parser.add_option(option_value,
+                              sharg::config{.short_id = 'j',
+                                            .long_id = "jint",
+                                            .description = "this is a required int option.",
+                                            .required = true});
+    sub_sub_parser.add_option(option_value_string,
+                              sharg::config{.short_id = 's',
+                                            .long_id = "string",
+                                            .description = "this is a string option (advanced).",
+                                            .advanced = true,
+                                            .required = false});
+    sub_sub_parser.add_option(option_value_path,
+                              sharg::config{.short_id = '\0',
+                                            .long_id = "path04",
+                                            .description = "a output file.",
+                                            .validator = sharg::output_file_validator{}});
+
+    std::string expected_short =
+        "label: test_parser-index-show\n"
+        "doc: \"\"\n"
+        "inputs:\n"
+        "  jint:\n"
+        "    doc: this is a required int option.\n"
+        "    type: long\n"
+        "    inputBinding:\n"
+        "      prefix: --jint\n"
+        "  string:\n"
+        "    doc: \"this is a string option (advanced). Default: \\\"\\\"\"\n"
+        "    type: string?\n"
+        "    inputBinding:\n"
+        "      prefix: --string\n"
+        "  path04:\n"
+        "    doc: \"a output file. Default: \\\"\\\". The output file must not exist already and write permissions "
+        "must be granted.\"\n"
+        "    type: string?\n"
+        "    inputBinding:\n"
+        "      prefix: --path04\n"
+        "outputs:\n"
+        "  path04:\n"
+        "    type: File?\n"
+        "    outputBinding:\n"
+        "      glob: $(inputs.path04)\n"
+        "cwlVersion: v1.2\n"
+        "class: CommandLineTool\n"
+        "baseCommand:\n"
+        "  - test_parser\n"
+        "  - index\n"
+        "  - show\n";
+    EXPECT_EQ(get_parse_cout_on_exit(sub_sub_parser), expected_short);
+}
 #endif

test/unit/parser/subcommand_test.cpp

@@ -245,3 +245,29 @@ TEST_F(subcommand_test, option_value_is_special_command)
     EXPECT_NO_THROW(parser.parse());
     EXPECT_EQ(value, "--help");
 }
+
+TEST_F(subcommand_test, recursive_subcommands)
+{
+    auto parser = get_subcommand_parser({"index", "show", "--help"}, {"index"});
+    EXPECT_NO_THROW(parser.parse());
+
+    auto & sub_parser = parser.get_sub_parser();
+    ASSERT_EQ(sub_parser.info.app_name, "test_parser-index");
+    sub_parser.add_subcommands({"show"});
+    EXPECT_NO_THROW(sub_parser.parse());
+
+    auto & sub_sub_parser = sub_parser.get_sub_parser();
+    ASSERT_EQ(sub_sub_parser.info.app_name, "test_parser-index-show");
+    clear_and_add_option(sub_sub_parser);
+
+    std::string expected_sub_sub_full_help = "test_parser-index-show\n"
+                                             "======================\n"
+                                             "\n"
+                                             "OPTIONS\n"
+                                             "    -o (std::string)\n"
+                                             "          Default: \"\"\n"
+                                             "\n"
+                                           + basic_options_str + '\n' + version_str("-index-show");
+
+    EXPECT_EQ(get_parse_cout_on_exit(sub_sub_parser), expected_sub_sub_full_help);
+}