[clang-tidy] NFC refactor lexer-utils to be usable without ASTContext

Summary:
This patch is a small refactoring necessary for
'readability-isolate-declaration' and does not introduce functional changes.
It allows to use the utility functions without a full `ASTContext` and requires only the `SourceManager` and the `LangOpts`.

Reviewers: alexfh, aaron.ballman, hokein

Reviewed By: alexfh

Subscribers: nemanjai, xazax.hun, kbarton, cfe-commits

Tags: #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D52684

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@343850 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 9 insertions, 12 deletions

diff --git a/clang-tidy/utils/FixItHintUtils.cpp b/clang-tidy/utils/FixItHintUtils.cpp
index 0627e519..9da93653 100644
--- a/clang-tidy/utils/FixItHintUtils.cpp
+++ b/clang-tidy/utils/FixItHintUtils.cpp
@@ -18,7 +18,8 @@ namespace fixit {
 
 FixItHint changeVarDeclToReference(const VarDecl &Var, ASTContext &Context) {
   SourceLocation AmpLocation = Var.getLocation();
-  auto Token = utils::lexer::getPreviousToken(Context, AmpLocation);
+  auto Token = utils::lexer::getPreviousToken(
+      AmpLocation, Context.getSourceManager(), Context.getLangOpts());
   if (!Token.is(tok::unknown))
     AmpLocation = Lexer::getLocForEndOfToken(Token.getLocation(), 0,
                                              Context.getSourceManager(),
diff --git a/clang-tidy/utils/LexerUtils.cpp b/clang-tidy/utils/LexerUtils.cpp
index d0272191..1b52347e 100644
--- a/clang-tidy/utils/LexerUtils.cpp
+++ b/clang-tidy/utils/LexerUtils.cpp
@@ -14,19 +14,15 @@ namespace tidy {
 namespace utils {
 namespace lexer {
 
-Token getPreviousToken(const ASTContext &Context, SourceLocation Location,
-                       bool SkipComments) {
-  const auto &SourceManager = Context.getSourceManager();
+Token getPreviousToken(SourceLocation Location, const SourceManager &SM,
+                       const LangOptions &LangOpts, bool SkipComments) {
   Token Token;
   Token.setKind(tok::unknown);
   Location = Location.getLocWithOffset(-1);
-  auto StartOfFile =
-      SourceManager.getLocForStartOfFile(SourceManager.getFileID(Location));
+  auto StartOfFile = SM.getLocForStartOfFile(SM.getFileID(Location));
   while (Location != StartOfFile) {
-    Location = Lexer::GetBeginningOfToken(Location, SourceManager,
-                                          Context.getLangOpts());
-    if (!Lexer::getRawToken(Location, Token, SourceManager,
-                            Context.getLangOpts()) &&
+    Location = Lexer::GetBeginningOfToken(Location, SM, LangOpts);
+    if (!Lexer::getRawToken(Location, Token, SM, LangOpts) &&
         (!SkipComments || !Token.is(tok::comment))) {
       break;
     }
diff --git a/clang-tidy/utils/LexerUtils.h b/clang-tidy/utils/LexerUtils.h
index f7bcd6f6..0eb5e56e 100644
--- a/clang-tidy/utils/LexerUtils.h
+++ b/clang-tidy/utils/LexerUtils.h
@@ -19,8 +19,8 @@ namespace utils {
 namespace lexer {
 
 /// Returns previous token or ``tok::unknown`` if not found.
-Token getPreviousToken(const ASTContext &Context, SourceLocation Location,
-                       bool SkipComments = true);
+Token getPreviousToken(SourceLocation Location, const SourceManager &SM,
+                       const LangOptions &LangOpts, bool SkipComments = true);
 
 } // namespace lexer
 } // namespace utils