command_line/options: Refactored to properly recursively traverse opt…

…ionSet_t's for all parsed arguments in the path to finding the right help to display
bad-alloc-heavy-industries · Oct 13, 2024 · 7c66173 · 7c66173
1 parent 79e2a9a
commit 7c66173
Show file tree

Hide file tree

Showing 2 changed files with 49 additions and 39 deletions.
diff --git a/impl/command_line/options.cxx b/impl/command_line/options.cxx
@@ -162,6 +162,25 @@ namespace substrate::commandLine
 		}
 	}
 
+	bool optionSet_t::displayHelp(const arguments_t &args) const noexcept
+	{
+		const auto arg{args[_metaName]};
+		// We found a match so we now need to find out which one matched
+		if (arg)
+		{
+			// Extract the choice made and loop through the possible choice alternations
+			const auto &choice{std::get<choice_t>(*arg)};
+			for (const auto &option : _alternations)
+			{
+				// If the alternation matches the one actually selected, display it
+				if (option.matches(choice.value()))
+					option.suboptions().displayHelp(choice.arguments(), _metaName);
+			}
+		}
+		// Return if we found a match
+		return arg;
+	}
+
 	// Implementation of the innards of optionSet_t as otherwise we get compile errors
 	const optionAlternation_t *optionSet_t::begin() const noexcept
 		{ return _alternations.begin(); }
@@ -284,12 +303,29 @@ namespace substrate::commandLine
 		}
 
 		// NOTLINENEXTLINE(readability-convert-member-functions-to-static)
-		void optionsHolder_t::displayHelp(const std::string_view &optionsTitle) const noexcept
+		void optionsHolder_t::displayHelp(const arguments_t &args, const std::string_view &optionsTitle) const noexcept
 		{
-			// Figure out how much padding is needed to make everything neat
+			// First check to see if we should actually be displaying some alternation's help
+			for (const auto &option : *this)
+			{
+				const auto handled
+				{
+					std::visit(match_t
+					{
+						[](const option_t &) { return false; },
+						[&](const optionSet_t &optionSet) { return optionSet.displayHelp(args); },
+					}, option)
+				};
+				// If we have indeed managed to handle things, finish early
+				if (handled)
+					return;
+			}
+
+			// No optionSet_t's to traverse, so now figure out how much padding is needed to make everything neat
 			const auto padding{displayPadding()};
 			std::vector<optionSet_t> optionSets{};
 
+			// Display the title block for the non-alternation options
 			if (optionsTitle.empty())
 				console.writeln("Options:"sv);
 			else
@@ -320,36 +356,8 @@ namespace substrate::commandLine
 				console.writeln(_helpHeader);
 				console.writeln();
 			}
-			// Now see if any of the option sets appear in the arguments parsed
-			auto foundMatch{false};
-			for (const auto &option : _options)
-			{
-				foundMatch |= std::visit(match_t
-				{
-					[](const option_t &) { return false; },
-					[&](const optionSet_t &optionSet) -> bool
-					{
-						const auto arg{args[optionSet.metaName()]};
-						// We found a match so we now need to find out which one matched
-						if (arg)
-						{
-							// Extract the choice made and loop through the possible choice alternations
-							const auto &choice{std::get<choice_t>(*arg)};
-							for (const auto &alternation : optionSet)
-							{
-								// If the alternation matches the one actually selected, display it
-								if (alternation.matches(choice.value()))
-									alternation.suboptions().displayHelp(optionSet.metaName());
-							}
-						}
-						// Return if we found a match
-						return arg;
-					},
-				}, option);
-			}
-			// If we found no matching options, display the base help
-			if (!foundMatch)
-				_options.displayHelp();
+			// Now display the appropriate options help
+			_options.displayHelp(args);
 
 			// Finish up by displaying the help footer
 			if (!_helpFooter.empty())

diff --git a/substrate/command_line/options b/substrate/command_line/options
@@ -68,6 +68,7 @@ namespace substrate::commandLine
 	};
 
 	struct optionAlternation_t;
+	struct arguments_t;
 	using optionValueParser_t = std::optional<std::any> (*)(const std::string_view &) noexcept;
 
 	// A singular command line option such as a simple flag
@@ -222,6 +223,7 @@ namespace substrate::commandLine
 			matches(const std::string_view &argument) const noexcept;
 		[[nodiscard]] size_t displayPadding() const noexcept;
 		void displayHelp(size_t padding = 0U) const noexcept;
+		bool displayHelp(const arguments_t &args) const noexcept;
 
 		[[nodiscard]] const optionAlternation_t *begin() const noexcept;
 		[[nodiscard]] const optionAlternation_t *end() const noexcept;
@@ -264,7 +266,7 @@ namespace substrate::commandLine
 			constexpr optionsItem_t operator [](const size_t index) const { return optionAt<0U>(index, _options); }
 			constexpr auto &options() const noexcept { return _options; }
 
-			void displayHelp(const std::string_view &optionsTitle) const noexcept;
+			void displayHelp(const arguments_t &args, const std::string_view &optionsTitle) const noexcept;
 		};
 
 		template<typename... options_t> optionsStorage_t(const std::tuple<options_t...> &) ->
@@ -332,14 +334,15 @@ namespace substrate::commandLine
 			constexpr auto end() const noexcept { return optionsIterator_t{storage, length, indexFn}; }
 
 			[[nodiscard]] size_t displayPadding() const noexcept;
-			void displayHelp(const std::string_view &optionsTitle) const noexcept;
+			void displayHelp(const arguments_t &args, const std::string_view &optionsTitle) const noexcept;
 		};
 
 		template<typename... options_t>
-			void optionsStorage_t<options_t...>::displayHelp(const std::string_view &optionsTitle) const noexcept
+			void optionsStorage_t<options_t...>::displayHelp(const arguments_t &args,
+				const std::string_view &optionsTitle) const noexcept
 		{
 			optionsHolder_t holder{*this};
-			holder.displayHelp(optionsTitle);
+			holder.displayHelp(args, optionsTitle);
 		}
 	}
 
@@ -363,7 +366,8 @@ namespace substrate::commandLine
 		[[nodiscard]] constexpr auto end() const noexcept { return _options.end(); }
 
 		[[nodiscard]] size_t displayPadding() const noexcept { return _options.displayPadding(); }
-		void displayHelp(std::string_view optionsTitle = {}) const noexcept { _options.displayHelp(optionsTitle); }
+		void displayHelp(const arguments_t &args, std::string_view optionsTitle = {}) const noexcept
+			{ _options.displayHelp(args, optionsTitle); }
 	};
 
 	namespace internal
@@ -427,8 +431,6 @@ namespace substrate::commandLine
 		[[nodiscard]] constexpr auto &helpText() const noexcept { return _help; }
 	};
 
-	struct arguments_t;
-
 	namespace internal
 	{
 		struct optionsRoot_t final