Fix setting breakpoint in non-finalized class

runtime/vm/debugger.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/debugger.h"
 
 #include "include/dart_api.h"
 
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
@@ skipping 1374 matching lines @@
   Class& cls = Class::Handle(isolate_);
   Array& functions = Array::Handle(isolate_);
   GrowableObjectArray& closures = GrowableObjectArray::Handle(isolate_);
   Function& function = Function::Handle(isolate_);
 
   const ClassTable& class_table = *isolate_->class_table();
   const intptr_t num_classes = class_table.NumCids();
   for (intptr_t i = 1; i < num_classes; i++) {
     if (class_table.HasValidClassAt(i)) {
       cls = class_table.At(i);
+      // If the class is not finalized, e.g. if it hasn't been parsed
+      // yet entirely, we can ignore it. If it contains a function with
+      // a latent breakpoint, we will detect it if and when the function
+      // gets compiled.
+      if (!cls.is_finalized()) {
+        continue;
+      }
       // Note: we need to check the functions of this class even if
       // the class is defined in a differenct 'script'. There could
       // be mixin functions from the given script in this class.
       functions = cls.functions();
       if (!functions.IsNull()) {
         const intptr_t num_functions = functions.Length();
         for (intptr_t pos = 0; pos < num_functions; pos++) {
           function ^= functions.At(pos);
           ASSERT(!function.IsNull());
           // Check token position first to avoid unnecessary calls
@@ skipping 63 matching lines @@
   Array& functions = Array::Handle(isolate_);
   GrowableObjectArray& closures = GrowableObjectArray::Handle(isolate_);
   Function& function = Function::Handle(isolate_);
   Function& best_fit = Function::Handle(isolate_);
 
   const ClassTable& class_table = *isolate_->class_table();
   const intptr_t num_classes = class_table.NumCids();
   for (intptr_t i = 1; i < num_classes; i++) {
     if (class_table.HasValidClassAt(i)) {
       cls = class_table.At(i);
-      // Note: we need to check the functions of this class even if
-      // the class is defined in a differenct 'script'. There could
+      // Note: if this class has been parsed and finalized already,
+      // we need to check the functions of this class even if
+      // it is defined in a differenct 'script'. There could
       // be mixin functions from the given script in this class.
+      // However, if this class is not parsed yet (not finalized),
+      // we can ignore it and avoid the side effect of parsing it.
+      if ((cls.script() != script.raw()) && !cls.is_finalized()) {
+        continue;
+      }
+      // Parse class definition if not done yet.
+      cls.EnsureIsFinalized(isolate_);

[Ivan Posva, 2014/01/03 20:21:13]

What happens if there is a compilation failure during the compilation? We should
probably drop the compilation failure on the floor and wait for some other code
to run into it again.

[hausner, 2014/01/03 20:52:52]

The compilation error gets dropped and the class remains unfinalized. It appears
to have no class members. When the program later references the class, it will
produce an appropriate compilation error.

       functions = cls.functions();
       if (!functions.IsNull()) {
         const intptr_t num_functions = functions.Length();
         for (intptr_t pos = 0; pos < num_functions; pos++) {
           function ^= functions.At(pos);
           ASSERT(!function.IsNull());
           if (FunctionContains(function, script, token_pos)) {
             SelectBestFit(&best_fit, &function);
           }
         }
@@ skipping 780 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart