add an optional help message string to the version_add flag if desired to override

Author: phlptp

include/CLI/App.hpp

@@ -719,7 +719,9 @@ class App {
     }
 
     /// Set a version flag and version display string, replace the existing one if present
-    Option *set_version_flag(std::string flag_name = "", const std::string &versionString = "") {
+    Option *set_version_flag(std::string flag_name = "",
+                             const std::string &versionString = "",
+                             const std::string &version_help = "Display program version information and exit") {
         // take flag_description by const reference otherwise add_flag tries to assign to version_description
         if(version_ptr_ != nullptr) {
             remove_option(version_ptr_);
@@ -731,15 +733,16 @@ class App {
             version_ptr_ = add_flag_callback(
                 flag_name,
                 [versionString]() { throw(CLI::CallForVersion(versionString, 0)); },
-                "Display program version information and exit");
+                version_help);
             version_ptr_->configurable(false);
         }
 
         return version_ptr_;
     }
     /// Generate the version string through a callback function
-    Option *set_version_flag(std::string flag_name, std::function<std::string()> vfunc) {
-        // take flag_description by const reference otherwise add_flag tries to assign to version_description
+    Option *set_version_flag(std::string flag_name,
+                             std::function<std::string()> vfunc,
+                             const std::string &version_help = "Display program version information and exit") {
         if(version_ptr_ != nullptr) {
             remove_option(version_ptr_);
             version_ptr_ = nullptr;
@@ -750,7 +753,7 @@ class App {
             version_ptr_ = add_flag_callback(
                 flag_name,
                 [vfunc]() { throw(CLI::CallForVersion(vfunc(), 0)); },
-                "Display program version information and exit");
+                version_help);
             version_ptr_->configurable(false);
         }
 

tests/HelpTest.cpp

@@ -1220,6 +1220,21 @@ TEST_CASE("TVersion: callback_flag", "[help]") {
     CHECK_THAT(vers, Contains("VERSION"));
 }
 
+TEST_CASE("TVersion: help", "[help]") {
+
+    CLI::App app;
+
+    app.set_version_flag("-v,--version", "version_string", "help_for_version");
+
+    auto hvers = app.help();
+    CHECK_THAT(hvers, Contains("help_for_version"));
+
+    app.set_version_flag(
+        "-v", []() { return std::string("VERSION2 " CLI11_VERSION); }, "help_for_version2");
+    hvers = app.help();
+    CHECK_THAT(hvers, Contains("help_for_version2"));
+}
+
 TEST_CASE("TVersion: parse_throw", "[help]") {
 
     CLI::App app;