[SourceKit] Only verify the solver-based cursor info implementation if requested

This allows us to mark expected deviations between the AST-based and the solver-based implementation in the stress tester as XFails without breaking actual clients

We always verify if a cursor info request is issued through `sourcekitd-test`.

Author: ahoppen

tools/SourceKit/include/SourceKit/Core/LangSupport.h

@@ -938,6 +938,7 @@ class LangSupport {
       bool SymbolGraph, bool CancelOnSubsequentRequest,
       ArrayRef<const char *> Args, Optional<VFSOptions> vfsOptions,
       SourceKitCancellationToken CancellationToken,
+      bool VerifySolverBasedCursorInfo,
       std::function<void(const RequestResult<CursorInfoData> &)> Receiver) = 0;
 
   virtual void

tools/SourceKit/lib/SwiftLang/SwiftLangSupport.h

@@ -627,6 +627,7 @@ class SwiftLangSupport : public LangSupport {
                      ArrayRef<const char *> Args,
                      Optional<VFSOptions> vfsOptions,
                      SourceKitCancellationToken CancellationToken,
+                     bool VerifySolverBasedCursorInfo,
                      std::function<void(const RequestResult<CursorInfoData> &)>
                          Receiver) override;
 

tools/SourceKit/lib/SwiftLang/SwiftSourceDocInfo.cpp

@@ -1885,6 +1885,7 @@ void SwiftLangSupport::getCursorInfo(
     bool SymbolGraph, bool CancelOnSubsequentRequest,
     ArrayRef<const char *> Args, Optional<VFSOptions> vfsOptions,
     SourceKitCancellationToken CancellationToken,
+    bool VerifySolverBasedCursorInfo,
     std::function<void(const RequestResult<CursorInfoData> &)> Receiver) {
 
   std::string error;

tools/SourceKit/tools/sourcekitd-test/sourcekitd-test.cpp

@@ -770,6 +770,8 @@ static int handleTestInvocation(TestOptions Opts, TestOptions &InitOpts) {
     } else {
       sourcekitd_request_dictionary_set_int64(Req, KeyOffset, ByteOffset);
     }
+    sourcekitd_request_dictionary_set_int64(Req, KeyVerifySolverBasedCursorInfo,
+                                            true);
     addRequestOptionsDirect(Req, Opts);
     break;
   case SourceKitRequest::RangeInfo: {

tools/SourceKit/tools/sourcekitd/lib/Service/Requests.cpp

@@ -1128,10 +1128,13 @@ static void handleSemanticRequest(
       Req.getInt64(KeyRetrieveRefactorActions, Actionables, /*isOptional=*/true);
       int64_t SymbolGraph = false;
       Req.getInt64(KeyRetrieveSymbolGraph, SymbolGraph, /*isOptional=*/true);
+      int64_t VerifySolverBasedCursorInfo = false;
+      Req.getInt64(KeyVerifySolverBasedCursorInfo, VerifySolverBasedCursorInfo,
+                   /*isOptional=*/true);
       return Lang.getCursorInfo(
           *SourceFile, Offset, Length, Actionables, SymbolGraph,
           CancelOnSubsequentRequest, Args, std::move(vfsOptions),
-          CancellationToken,
+          CancellationToken, VerifySolverBasedCursorInfo,
           [Rec](const RequestResult<CursorInfoData> &Result) {
             reportCursorInfo(Result, Rec);
           });

utils/gyb_sourcekit_support/UIDs.py

@@ -189,6 +189,7 @@ def __init__(self, internal_name, external_name):
     KEY('OptimizeForIDE', 'key.optimize_for_ide'),
     KEY('RequiredBystanders', 'key.required_bystanders'),
     KEY('ReusingASTContext', 'key.reusingastcontext'),
+    KEY('VerifySolverBasedCursorInfo', 'key.verifysolverbasedcursorinfo'),
     KEY('CompletionMaxASTContextReuseCount',
         'key.completion_max_astcontext_reuse_count'),
     KEY('CompletionCheckDependencyInterval',