Do case-sensitive search for category first in slangc -h (#8142)

Related to #7969

In the slangc help text we have two categories, the option category
`Target` and the values category `target`, where the names only differ
by case. The help parser finds the category in the list by the
case-insensitive name, so `slangc -h Target` and `slangc -h target` will
both print the `Target` help text and never the `target` help text.

This commit replaces the case-insensitive name search with a
case-sensitive one, and then only if the case-sensitive check fails do
we do a case-insensitive search.

That way, if the user uses `Target` they get the `Target` text, for
`target` they get the `target` text. If they use something like
`Capability`, a category that does not exist but whose name is
upper-case of the value category `capability`, they will still get the
help text for `capability` as before as a fallback.

---------

Co-authored-by: slangbot <ellieh+slangbot@nvidia.com>
Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/source/slang/slang-options.cpp b/source/slang/slang-options.cpp
index e777d27bc..b0eb1748d 100644
--- a/source/slang/slang-options.cpp
+++ b/source/slang/slang-options.cpp
@@ -2009,8 +2009,14 @@ SlangResult OptionsParser::_parseHelp(const CommandLineArg& arg)
     {
         auto catArg = m_reader.getArgAndAdvance();
 
-        categoryIndex =
-            m_cmdOptions->findCategoryByCaseInsensitiveName(catArg.value.getUnownedSlice());
+        categoryIndex = m_cmdOptions->findCategoryByName(catArg.value.getUnownedSlice());
+
+        if (categoryIndex < 0)
+        {
+            categoryIndex =
+                m_cmdOptions->findCategoryByCaseInsensitiveName(catArg.value.getUnownedSlice());
+        }
+
         if (categoryIndex < 0)
         {
             m_sink->diagnose(catArg.loc, Diagnostics::unknownHelpCategory);