[5.0][sourcekitd] Fix cursor resolving when pointing inside string interpolations of return statements

include/swift/IDE/Utils.h

@@ -233,9 +233,8 @@ class CursorInfoResolver : public SourceEntityWalker {
   bool visitDeclarationArgumentName(Identifier Name, SourceLoc StartLoc,
                                     ValueDecl *D) override;
   bool visitModuleReference(ModuleEntity Mod, CharSourceRange Range) override;
-  bool rangeContainsLoc(SourceRange Range) const {
-    return getSourceMgr().rangeContainsTokenLoc(Range, LocToResolve);
-  }
+  bool rangeContainsLoc(SourceRange Range) const;
+  bool rangeContainsLoc(CharSourceRange Range) const;
   bool isDone() const { return CursorInfo.isValid(); }
   bool tryResolve(ValueDecl *D, TypeDecl *CtorTyRef, ExtensionDecl *ExtTyRef,
                   SourceLoc Loc, bool IsRef, Type Ty = Type());

lib/IDE/SwiftSourceDocInfo.cpp

@@ -149,9 +149,17 @@ bool CursorInfoResolver::walkToDeclPost(Decl *D) {
 }
 
 bool CursorInfoResolver::walkToStmtPre(Stmt *S) {
+  // Getting the character range for the statement, to account for interpolation
+  // strings. The token range for the interpolation string is the whole string,
+  // with begin/end locations pointing at the beginning of the string, so if
+  // there is a token location inside the string, it will seem as if it is out
+  // of the source range, unless we convert to character range.
+
   // FIXME: Even implicit Stmts should have proper ranges that include any
   // non-implicit Stmts (fix Stmts created for lazy vars).
-  if (!S->isImplicit() && !rangeContainsLoc(S->getSourceRange()))
+  if (!S->isImplicit() &&
+      !rangeContainsLoc(Lexer::getCharSourceRangeFromSourceRange(
+          getSourceMgr(), S->getSourceRange())))
     return false;
   return !tryResolve(S);
 }
@@ -249,6 +257,14 @@ SourceManager &NameMatcher::getSourceMgr() const {
   return SrcFile.getASTContext().SourceMgr;
 }
 
+bool CursorInfoResolver::rangeContainsLoc(SourceRange Range) const {
+  return getSourceMgr().rangeContainsTokenLoc(Range, LocToResolve);
+}
+
+bool CursorInfoResolver::rangeContainsLoc(CharSourceRange Range) const {
+  return Range.contains(LocToResolve);
+}
+
 std::vector<ResolvedLoc> NameMatcher::resolve(ArrayRef<UnresolvedLoc> Locs, ArrayRef<Token> Tokens) {
 
   // Note the original indices and sort them in reverse source order

test/SourceKit/CursorInfo/cursor_info_expressions.swift

@@ -2,15 +2,26 @@ protocol P1 {}
 
 struct S1 : P1 {}
 
-func test(_ o: P1?) {
+func test(_ o: P1?) -> String {
   switch o {
   case let s as S1:
     test(s)
   default:
     test(o)
   }
+
+  _ = "\(o)"
+  return "\(o)"
 }
 
 // RUN: %sourcekitd-test -req=cursor -pos=7:17 %s -- %s | %FileCheck -check-prefix=CHECK1 %s
 // CHECK1: source.lang.swift.ref.struct (3:8-3:10)
 // CHECK1: S1
+
+// RUN: %sourcekitd-test -req=cursor -pos=13:10 %s -- %s | %FileCheck -check-prefix=CHECK2 %s
+// CHECK2: source.lang.swift.ref.var.local (5:13-5:14)
+// CHECK2: P1?
+
+// RUN: %sourcekitd-test -req=cursor -pos=14:13 %s -- %s | %FileCheck -check-prefix=CHECK3 %s
+// CHECK3: source.lang.swift.ref.var.local (5:13-5:14)
+// CHECK3: P1?