Run field initializers for new instance fields after a reload

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index bf063f3ffe159961bc70fc0b7978785fd1a9ef6b..6c3389fe4e9b171d757f259a55c762f3cd50cdb3 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -3059,10 +3059,10 @@ static RawString* BuildClosureSource(const Array& formal_params,
 }
 
 
-static RawFunction* EvaluateHelper(const Class& cls,
-                                   const String& expr,
-                                   const Array& param_names,
-                                   bool is_static) {
+RawFunction* Function::EvaluateHelper(const Class& cls,
+                                      const String& expr,
+                                      const Array& param_names,
+                                      bool is_static) {
   const String& func_src =
       String::Handle(BuildClosureSource(param_names, expr));
   Script& script = Script::Handle();
@@ -3099,7 +3099,8 @@ RawObject* Class::Evaluate(const String& expr,
   }
 
   const Function& eval_func =
-      Function::Handle(EvaluateHelper(*this, expr, param_names, true));
+      Function::Handle(
+          Function::EvaluateHelper(*this, expr, param_names, true));
   const Object& result =
       Object::Handle(DartEntry::InvokeFunction(eval_func, param_values));
   return result.raw();
@@ -7647,6 +7648,38 @@ RawField* Field::Clone(const Field& original) const {
 }
 
 
+RawString* Field::InitializingExpression() const {

[rmacnak, 2016/11/09 00:36:32]

Copying the initializer like this means any stacktrace running this expression
will have the wrong source position. Fixing this and the analogous problem with
eval expressions probably involving adding new function kinds, so just add a
TODO for this CL.

+  Thread* thread = Thread::Current();
+  Zone* zone = thread->zone();
+  const class Script& scr = Script::Handle(zone, Script());
+  ASSERT(!scr.IsNull());
+  const TokenStream& tkns = TokenStream::Handle(zone, scr.tokens());
+  if (tkns.IsNull()) {
+    ASSERT(Dart::snapshot_kind() == Snapshot::kAppNoJIT);
+    return String::null();
+  }
+  TokenStream::Iterator tkit(zone,
+                             tkns,
+                             token_pos());
+  ASSERT(Token::IsIdentifier(tkit.CurrentTokenKind()));
+#if defined(DEBUG)
+  const String& literal = String::Handle(zone, tkit.CurrentLiteral());
+  ASSERT(literal.raw() == name());
+#endif
+  tkit.Advance();
+  if (tkit.CurrentTokenKind() != Token::kASSIGN) {
+    return String::null();
+  }
+  tkit.Advance();
+  const TokenPosition start_of_expression = tkit.CurrentPosition();
+  while (tkit.CurrentTokenKind() != Token::kSEMICOLON) {
+    tkit.Advance();
+  }
+  const TokenPosition end_of_expression = tkit.CurrentPosition();
+  return scr.GetSnippet(start_of_expression, end_of_expression);
+}
+
+
 RawString* Field::UserVisibleName() const {
   if (FLAG_show_internal_names) {
     return name();
@@ -9115,6 +9148,18 @@ RawString* Script::GetLine(intptr_t line_number, Heap::Space space) const {
 }
 
 
+RawString* Script::GetSnippet(TokenPosition from, TokenPosition to) const {
+  intptr_t from_line;
+  intptr_t from_column;
+  intptr_t to_line;
+  intptr_t to_column;
+  GetTokenLocation(from, &from_line, &from_column);
+  GetTokenLocation(to, &to_line, &to_column);
+  return GetSnippet(from_line, from_column,
+                    to_line, to_column);
+}
+
+
 RawString* Script::GetSnippet(intptr_t from_line,
                               intptr_t from_column,
                               intptr_t to_line,
@@ -15465,7 +15510,8 @@ RawObject* Instance::Evaluate(const Class& method_cls,
                               const Array& param_names,
                               const Array& param_values) const {
   const Function& eval_func =
-      Function::Handle(EvaluateHelper(method_cls, expr, param_names, false));
+      Function::Handle(
+          Function::EvaluateHelper(method_cls, expr, param_names, false));
   const Array& args = Array::Handle(Array::New(1 + param_values.Length()));
   PassiveObject& param = PassiveObject::Handle();
   args.SetAt(0, *this);