Bug 1282172 - Detect enum constants generated by macros when generating the Searchfox index. r=billm

MozReview-Commit-ID: 5RUsVSMTU8

--HG--
extra : rebase_source : 32f803de363aaaaa8df9c3d0eac31653ecb3de48

build/clang-plugin/mozsearch-plugin/MozsearchIndexer.cpp

@@ -1042,6 +1042,16 @@ public:
 
   bool VisitNamedDecl(NamedDecl *D) {
     SourceLocation Loc = D->getLocation();
+
+    if (isa<EnumConstantDecl>(D) && SM.isMacroBodyExpansion(Loc)) {
+      // for enum constants generated by macro expansion, update location
+      // to point to the expansion location as that is more useful. We might
+      // want to do this for more token types but until we have good regression
+      // testing for the Indexer it's best to be as conservative and explicit
+      // as possible with the changes.
+      Loc = SM.getFileLoc(Loc);
+    }
+
     normalizeLocation(&Loc);
     if (!isInterestingLocation(Loc)) {
       return true;