[clang-tidy] Don't emit the whole spelling include header in include-…

…cleaner diagnostic message

To keep the message short and consistent with clangd, and the diagnostics are
attached to the #include line, users have enough context to understand the whole #include.

Differential Revision: https://reviews.llvm.org/D154434

clang-tools-extra/clang-tidy/misc/IncludeCleanerCheck.cpp

@@ -34,6 +34,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Path.h"
 #include "llvm/Support/Regex.h"
 #include <optional>
 #include <string>
@@ -171,7 +172,8 @@ void IncludeCleanerCheck::check(const MatchFinder::MatchResult &Result) {
 
   for (const auto *Inc : Unused) {
     diag(Inc->HashLocation, "included header %0 is not used directly")
-        << Inc->quote()
+        << llvm::sys::path::filename(Inc->Spelled,
+                                     llvm::sys::path::Style::posix)
         << FixItHint::CreateRemoval(CharSourceRange::getCharRange(
                SM->translateLineCol(SM->getMainFileID(), Inc->Line, 1),
                SM->translateLineCol(SM->getMainFileID(), Inc->Line + 1, 1)));

clang-tools-extra/test/clang-tidy/checkers/misc/include-cleaner.cpp

@@ -2,11 +2,11 @@
 #include "bar.h"
 // CHECK-FIXES: {{^}}#include "baz.h"{{$}}
 #include "foo.h"
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: included header "foo.h" is not used directly [misc-include-cleaner]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: included header foo.h is not used directly [misc-include-cleaner]
 // CHECK-FIXES: {{^}}
 // CHECK-FIXES: {{^}}#include <string>{{$}}
 #include <vector.h>
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: included header <vector.h> is not used directly [misc-include-cleaner]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: included header vector.h is not used directly [misc-include-cleaner]
 // CHECK-FIXES: {{^}}
 int BarResult = bar();
 int BazResult = baz();