From 33f3f2c038364630fb8e0614a443949279c030e8 Mon Sep 17 00:00:00 2001
From: Enrico Seiler <enrico.seiler@hotmail.de>
Date: Fri, 9 Feb 2024 14:11:31 +0100
Subject: [PATCH] resolve compatibility with old ctor

---
 include/sharg/parser.hpp                      | 13 ++++---
 test/snippet/readme_sneak_peek.cpp            | 34 +++++++++++++++++--
 test/unit/parser/parser_design_error_test.cpp |  2 +-
 3 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/include/sharg/parser.hpp b/include/sharg/parser.hpp
index 9205365d..76ca6d5e 100644
--- a/include/sharg/parser.hpp
+++ b/include/sharg/parser.hpp
@@ -681,8 +681,9 @@ class parser
      */
     parser_meta_data info;
 
-    /*!\brief Adds subcommands to the parser.
-     * \param[in] subcommands A list of subcommands.
+    /*!\brief Adds a subcommand to the parser.
+     * \param[in] subcommand The subcommand to add.
+     * \returns A pointer to the sub-parser if subcommand is encountered, nullptr otherwise.
      * \throws sharg::design_error if the subcommand name contains illegal characters.
      */
     [[nodiscard]] parser * add_subcommand(std::string subcommand)
@@ -701,7 +702,7 @@ class parser
         };
 
         auto & parser_subcommands = this->subcommands;
-        parser_subcommands.emplace_back(std::move(subcommand));
+        parser_subcommands.emplace_back(subcommand);
 
         std::ranges::sort(parser_subcommands);
         auto const [first, last] = std::ranges::unique(parser_subcommands);
@@ -709,7 +710,11 @@ class parser
 
         init();
 
-        return sub_parser.get();
+        // If a subcommand was already added via the constructor, we need to check if the subcommand is the same.
+        if (sub_parser && sub_parser->info.app_name == info.app_name + '-' + subcommand)
+            return sub_parser.get();
+        else
+            return nullptr;
     }
 
 private:
diff --git a/test/snippet/readme_sneak_peek.cpp b/test/snippet/readme_sneak_peek.cpp
index 11d169fb..ad6305c2 100644
--- a/test/snippet/readme_sneak_peek.cpp
+++ b/test/snippet/readme_sneak_peek.cpp
@@ -1,9 +1,16 @@
+// 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
+
+#define main test
+
 #include <sharg/all.hpp>
 
+#if 0
 int main(int argc, char ** argv)
 {
-    // sharg::parser git_parser{"git", argc, argv, sharg::update_notifications::on, {"pull", "push", "remote"}}; // NOT ALLOWED
-    sharg::parser git_parser{"git", argc, argv, sharg::update_notifications::on};
+    //                                                                           -------- Optional --------
+    sharg::parser git_parser{"git", argc, argv, sharg::update_notifications::on, {"pull", "push", "remote"}};
 
     if (auto pull_parser = git_parser.add_subcommand("pull"))
     {
@@ -47,3 +54,26 @@ int main(int argc, char ** argv)
 
     return 0;
 }
+#else
+int main(int argc, char ** argv)
+{
+    int val{};
+
+    sharg::parser parser{"Eat-Me-App", argc, argv};
+    parser.add_subsection("Eating Numbers");
+    parser.add_option(val, sharg::config{.short_id = 'i', .long_id = "int", .description = "Desc."});
+    parser.parse();
+
+    return 0;
+}
+#endif
+
+#undef main
+
+int main()
+{
+    std::string argv1{"./Eat-Me-App"}, argv2{"-h"};
+    std::array argv{argv1.data(), argv2.data()};
+
+    return test(argv.size(), argv.data());
+}
diff --git a/test/unit/parser/parser_design_error_test.cpp b/test/unit/parser/parser_design_error_test.cpp
index 308a4826..ae8d0bbe 100644
--- a/test/unit/parser/parser_design_error_test.cpp
+++ b/test/unit/parser/parser_design_error_test.cpp
@@ -263,7 +263,7 @@ TEST(parse_test, subcommand_parser_error)
         EXPECT_NO_THROW(top_level_parser.parse());
         EXPECT_EQ(true, flag_value);
 
-        EXPECT_THROW(top_level_parser.get_sub_parser(), sharg::design_error);
+        EXPECT_THROW(std::ignore = top_level_parser.get_sub_parser(), sharg::design_error);
     }
 
     // subcommand key word must only contain alpha numeric characters