[Syntax] Mark synthesized nodes as modifiable

This was an oversight in the original patch.
Also add corresponding tests.

1 files changed, 4 insertions, 0 deletions

diff --git a/clang/lib/Tooling/Syntax/Synthesis.cpp b/clang/lib/Tooling/Syntax/Synthesis.cpp
index cbd9579f4f0..aa01a34c761 100644
--- a/clang/lib/Tooling/Syntax/Synthesis.cpp
+++ b/clang/lib/Tooling/Syntax/Synthesis.cpp
@@ -13,6 +13,8 @@ using namespace clang;
 /// Should not be used for anything else.
 class syntax::FactoryImpl {
 public:
+  static void setCanModify(syntax::Node *N) { N->CanModify = true; }
+
   static void prependChildLowLevel(syntax::Tree *T, syntax::Node *Child,
                                    syntax::NodeRole R) {
     T->prependChildLowLevel(Child, R);
@@ -27,6 +29,7 @@ clang::syntax::Leaf *syntax::createPunctuation(clang::syntax::Arena &A,
   assert(Tokens.size() == 1);
   assert(Tokens.front().kind() == K);
   auto *L = new (A.allocator()) clang::syntax::Leaf(Tokens.begin());
+  FactoryImpl::setCanModify(L);
   L->assertInvariants();
   return L;
 }
@@ -34,6 +37,7 @@ clang::syntax::Leaf *syntax::createPunctuation(clang::syntax::Arena &A,
 clang::syntax::EmptyStatement *
 syntax::createEmptyStatement(clang::syntax::Arena &A) {
   auto *S = new (A.allocator()) clang::syntax::EmptyStatement;
+  FactoryImpl::setCanModify(S);
   FactoryImpl::prependChildLowLevel(S, createPunctuation(A, clang::tok::semi),
                                     NodeRole::Unknown);
   S->assertInvariants();