[sourcekitd] Fix potential race in semantic highlighting tests

In order to make range-shifting for semantic highlighting testable,
disable returning semantic information during an "open" request. This
has no real value anyway, since it only happens very rarely, and it
makes testing range shifting impossible to do deterministically.

rdar://problem/66386179

Author: benlangmuir

tools/SourceKit/lib/SwiftLang/SwiftEditor.cpp

@@ -1989,10 +1989,18 @@ void SwiftEditorDocument::parse(ImmutableTextSnapshotRef Snapshot,
   Impl.SyntaxInfo->parse();
 }
 
-void SwiftEditorDocument::readSyntaxInfo(EditorConsumer &Consumer) {
+static UIdent SemaDiagStage("source.diagnostic.stage.swift.sema");
+static UIdent ParseDiagStage("source.diagnostic.stage.swift.parse");
+
+void SwiftEditorDocument::readSyntaxInfo(EditorConsumer &Consumer, bool ReportDiags) {
   llvm::sys::ScopedLock L(Impl.AccessMtx);
 
   Impl.ParserDiagnostics = Impl.SyntaxInfo->getDiagnostics();
+  if (ReportDiags) {
+    Consumer.setDiagnosticStage(ParseDiagStage);
+    for (auto &Diag : Impl.ParserDiagnostics)
+      Consumer.handleDiagnostic(Diag, ParseDiagStage);
+  }
 
   SwiftSyntaxMap NewMap = SwiftSyntaxMap(Impl.SyntaxMap.Tokens.size() + 16);
 
@@ -2059,9 +2067,6 @@ void SwiftEditorDocument::readSemanticInfo(ImmutableTextSnapshotRef Snapshot,
       Consumer.handleSemanticAnnotation(Offset, Length, Kind, IsSystem);
   }
 
-  static UIdent SemaDiagStage("source.diagnostic.stage.swift.sema");
-  static UIdent ParseDiagStage("source.diagnostic.stage.swift.parse");
-
   // If there's no value returned for diagnostics it means they are out-of-date
   // (based on a different snapshot).
   if (SemaDiags.hasValue()) {
@@ -2304,7 +2309,6 @@ void SwiftEditorDocument::reportDocumentStructure(SourceFile &SrcFile,
 //===----------------------------------------------------------------------===//
 // EditorOpen
 //===----------------------------------------------------------------------===//
-
 void SwiftLangSupport::editorOpen(
     StringRef Name, llvm::MemoryBuffer *Buf, EditorConsumer &Consumer,
     ArrayRef<const char *> Args, Optional<VFSOptions> vfsOptions) {
@@ -2343,8 +2347,7 @@ void SwiftLangSupport::editorOpen(
     EditorDoc->updateSemaInfo();
   }
 
-  EditorDoc->readSyntaxInfo(Consumer);
-  EditorDoc->readSemanticInfo(Snapshot, Consumer);
+  EditorDoc->readSyntaxInfo(Consumer, /*ReportDiags=*/true);
 
   if (Consumer.syntaxTreeEnabled()) {
     assert(EditorDoc->getSyntaxTree().hasValue());
@@ -2506,7 +2509,8 @@ void SwiftLangSupport::editorReplaceText(StringRef Name,
     }
     EditorDoc->parse(Snapshot, *this, Consumer.syntaxTreeEnabled(),
                      SyntaxCachePtr);
-    EditorDoc->readSyntaxInfo(Consumer);
+    // Do not report syntactic diagnostics; will be handled in readSemanticInfo.
+    EditorDoc->readSyntaxInfo(Consumer, /*ReportDiags=*/false);
 
     // Log reuse information
     if (SyntaxCache.hasValue() && LogReuseRegions) {

tools/SourceKit/lib/SwiftLang/SwiftLangSupport.h

@@ -109,7 +109,7 @@ class SwiftEditorDocument :
   void parse(ImmutableTextSnapshotRef Snapshot, SwiftLangSupport &Lang,
              bool BuildSyntaxTree,
              swift::SyntaxParsingCache *SyntaxCache = nullptr);
-  void readSyntaxInfo(EditorConsumer &consumer);
+  void readSyntaxInfo(EditorConsumer &consumer, bool ReportDiags);
   void readSemanticInfo(ImmutableTextSnapshotRef Snapshot,
                         EditorConsumer& Consumer);
 

unittests/SourceKit/SwiftLang/EditingTest.cpp

@@ -388,13 +388,9 @@ TEST_F(EditTest, AnnotationsAfterOpen) {
   TestConsumer Consumer;
   open(DocName, Contents, Args, Consumer);
   ASSERT_FALSE(waitForDocUpdate()) << "timed out";
-  if (Consumer.DiagStage == SemaDiagStage) {
-    // AST already built, annotations are on Consumer.
-  } else {
-    // Re-query.
-    reset(Consumer);
-    replaceText(DocName, 0, 0, "", Consumer);
-  }
+  ASSERT_EQ(ParseDiagStage, Consumer.DiagStage);
+  reset(Consumer);
+  replaceText(DocName, 0, 0, "", Consumer);
 
   ASSERT_EQ(0u, Consumer.Diags.size());
   checkTokens(Consumer.Annotations, {
@@ -424,13 +420,9 @@ TEST_F(EditTest, AnnotationsAfterEdit) {
   TestConsumer Consumer;
   open(DocName, Contents, Args, Consumer);
   ASSERT_FALSE(waitForDocUpdate()) << "timed out";
-  if (Consumer.DiagStage == SemaDiagStage) {
-    // AST already built, annotations are on Consumer.
-  } else {
-    // Re-query.
-    reset(Consumer);
-    replaceText(DocName, 0, 0, "", Consumer);
-  }
+  ASSERT_EQ(ParseDiagStage, Consumer.DiagStage);
+  reset(Consumer);
+  replaceText(DocName, 0, 0, "", Consumer);
   checkTokens(Consumer.Annotations, {
     "[off=22 len=3 source.lang.swift.ref.struct system]",
   });