Fix VarDef::is_local; default cacheDirectory to ".ccls-cache"

src/config.h

@@ -33,8 +33,9 @@ struct Config {
   std::string compilationDatabaseCommand;
   // Directory containing compile_commands.json.
   std::string compilationDatabaseDirectory;
-  // Cache directory for indexed files.
-  std::string cacheDirectory;
+  // Cache directory for indexed files, either absolute or relative to the
+  // project root.
+  std::string cacheDirectory = ".ccls-cache";
   // Cache serialization format.
   //
   // "json" generates `cacheDirectory/.../xxx.json` files which can be pretty

src/indexer.h

@@ -190,7 +190,7 @@ struct VarDef : NameMixin<VarDef> {
   uint8_t storage = clang::SC_None;
 
   bool is_local() const {
-    return spell && spell->kind != SymbolKind::File &&
+    return spell && spell->kind == SymbolKind::Func &&
            storage == clang::SC_None;
   }