fix help

Author: HerrCai0907

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

@@ -38,6 +38,11 @@ static cl::desc desc(StringRef description) { return {description.ltrim()}; }
 static cl::OptionCategory ClangTidyCategory("clang-tidy options");
 
 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
+static cl::extrahelp ClangTidyParameterFileHelp(R"(
+Parameters files:
+  A large number of options or source files can be passed as parameter files
+  by use '@parameter-file' in the command line.
+)");
 static cl::extrahelp ClangTidyHelp(R"(
 Configuration files:
   clang-tidy attempts to read configuration for each source file from a

clang-tools-extra/docs/clang-tidy/index.rst

@@ -33,8 +33,9 @@ compilation options on the command line after ``--``:
 
   $ clang-tidy test.cpp -- -Imy_project/include -DMY_DEFINES ...
 
-If there are too many options to specify on the command line, you can store them
-in a parameter file, and use :program:`clang-tidy` with parameters file:
+If there are too many options or source files to specify on the command line,
+you can store them in a parameter file, and use :program:`clang-tidy` with that
+parameters file:
 
 .. code-block:: console
 
@@ -271,6 +272,9 @@ An overview of all the command-line options:
     automatically removed, but the rest of a relative path must be a
     suffix of a path in the compile command database.
 
+  Parameters files:
+    A large number of options or source files can be passed as parameter files
+    by use '@parameter-file' in the command line.
 
   Configuration files:
     clang-tidy attempts to read configuration for each source file from a