Refactor the unit tests for the SPARQL ANTLR parser

src/parser/data/OrderKey.h

@@ -8,9 +8,6 @@
 
 #include "../../engine/sparqlExpressions/SparqlExpressionPimpl.h"
 
-using std::string;
-using std::variant;
-
 /// Store an expression that appeared in an ORDER BY clause.
 class ExpressionOrderKey {
  public:
@@ -26,10 +23,10 @@ class ExpressionOrderKey {
 /// Store a variable that appeared in an ORDER BY clause.
 class VariableOrderKey {
  public:
-  string variable_;
+  std::string variable_;
   bool isDescending_;
   // ___________________________________________________________________________
-  explicit VariableOrderKey(string variable, bool isDescending = false)
+  explicit VariableOrderKey(std::string variable, bool isDescending = false)
       : variable_{std::move(variable)}, isDescending_{isDescending} {}
 
   bool operator==(const VariableOrderKey&) const = default;

src/parser/sparqlParser/SparqlQleverVisitor.h

@@ -57,7 +57,7 @@ class SparqlQleverVisitor : public SparqlAutomaticVisitor {
   using OperationsAndFilters =
       std::pair<vector<GraphPatternOperation>, vector<SparqlFilter>>;
   using OperationOrFilterAndMaybeTriples =
-      std::pair<variant<GraphPatternOperation, SparqlFilter>,
+      std::pair<std::variant<GraphPatternOperation, SparqlFilter>,
                 std::optional<GraphPatternOperation::BasicGraphPattern>>;
   using OperationOrFilter = std::variant<GraphPatternOperation, SparqlFilter>;
   using SubQueryAndMaybeValues =

src/util/SourceLocation.h

@@ -0,0 +1,22 @@
+//  Copyright 2022, University of Freiburg,
+//  Chair of Algorithms and Data Structures.
+//  Author: Julian Mundhahs (mundhahj@informatik.uni-freiburg.de)
+
+//  This compatibility header allows the usage of `ad_utility::source_location`
+//  (an alias to C++20's `std::source_location`) consistently across GCC and
+//  Clang. It is necessary, because `source_location` is currently still in the
+//  `std::experimental` namespace for Clang.
+
+#pragma once
+
+#if defined(__clang__)
+#include <experimental/source_location>
+namespace ad_utility {
+using source_location = std::experimental::source_location;
+}
+#else
+#include <source_location>
+namespace ad_utility {
+using source_location = std::source_location;
+}
+#endif