get_filename_component: make errors fatal

Make all errors in `get_filename_component` fatal.

Fixes: #20015

Source/cmGetFilenameComponentCommand.cxx

@@ -14,6 +14,7 @@ bool cmGetFilenameComponentCommand(std::vector<std::string> const& args,
 {
   if (args.size() < 3) {
     status.SetError("called with incorrect number of arguments");
+    cmSystemTools::SetFatalErrorOccured();
     return false;
   }
 
@@ -114,6 +115,7 @@ bool cmGetFilenameComponentCommand(std::vector<std::string> const& args,
   } else {
     std::string err = "unknown component " + args[2];
     status.SetError(err);
+    cmSystemTools::SetFatalErrorOccured();
     return false;
   }
 

Tests/RunCMake/get_filename_component/IncorrectArguments-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/get_filename_component/IncorrectArguments-stderr.txt

@@ -0,0 +1,4 @@
+^CMake Error at IncorrectArguments.cmake:1 \(get_filename_component\):
+  get_filename_component called with incorrect number of arguments
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)$

Tests/RunCMake/get_filename_component/IncorrectArguments.cmake

@@ -0,0 +1,2 @@
+get_filename_component(var)
+message("The error is fatal, so this should not print")

Tests/RunCMake/get_filename_component/RunCMakeTest.cmake

@@ -1,4 +1,5 @@
 include(RunCMake)
 
+run_cmake(IncorrectArguments)
 run_cmake(KnownComponents)
 run_cmake(UnknownComponent)

Tests/RunCMake/get_filename_component/UnknownComponent-stderr.txt

@@ -1,4 +1,4 @@
-CMake Error at UnknownComponent.cmake:1 \(get_filename_component\):
+^CMake Error at UnknownComponent.cmake:1 \(get_filename_component\):
   get_filename_component unknown component BOGUS
 Call Stack \(most recent call first\):
-  CMakeLists.txt:[0-9]+ \(include\)
+  CMakeLists.txt:[0-9]+ \(include\)$

Tests/RunCMake/get_filename_component/UnknownComponent.cmake

@@ -1 +1,2 @@
 get_filename_component(var "/path/to/filename.ext.in" BOGUS)
+message("The error is fatal, so this should not print")