harmony-scoping: Implement debugger support for script scope.

We add a new ScopeType, ScopeType.Script. The scope with
ScopeType.Script is always present in the scope chain (ScopeIterator
fakes it if neededi - i.e. if ScriptContext for a script has not been
allocated since that script has no lexical declarations).
ScriptScope reflects ScriptContextTable.

R=yurys@chromium.org,yangguo@chromium.org
BUG=v8:3690
LOG=N

Review URL: https://codereview.chromium.org/726643002

Cr-Commit-Position: refs/heads/master@{#25383}

src/mirror-debugger.js

@@ -193,13 +193,16 @@ PropertyAttribute.DontEnum   = DONT_ENUM;
 PropertyAttribute.DontDelete = DONT_DELETE;
 
 
-// A copy of the scope types from runtime.cc.
+// A copy of the scope types from runtime-debug.cc.
+// NOTE: these constants should be backward-compatible, so
+// add new ones to the end of this list.
 var ScopeType = { Global: 0,
                   Local: 1,
                   With: 2,
                   Closure: 3,
                   Catch: 4,
-                  Block: 5 };
+                  Block: 5,
+                  Script: 6 };
 
 
 // Mirror hierarchy:
@@ -2309,11 +2312,12 @@ ScopeMirror.prototype.scopeType = function() {
 
 
 ScopeMirror.prototype.scopeObject = function() {
-  // For local and closure scopes create a transient mirror as these objects are
-  // created on the fly materializing the local or closure scopes and
-  // therefore will not preserve identity.
+  // For local, closure and script scopes create a transient mirror
+  // as these objects are created on the fly materializing the local
+  // or closure scopes and therefore will not preserve identity.
   var transient = this.scopeType() == ScopeType.Local ||
-                  this.scopeType() == ScopeType.Closure;
+                  this.scopeType() == ScopeType.Closure ||
+                  this.scopeType() == ScopeType.Script;
   return MakeMirror(this.details_.object(), transient);
 };
 

src/runtime/runtime-debug.cc

@@ -801,6 +801,29 @@ MUST_USE_RESULT static MaybeHandle<JSObject> MaterializeLocalContext(
 }
 
 
+MUST_USE_RESULT static MaybeHandle<JSObject> MaterializeScriptScope(
+    Handle<GlobalObject> global) {
+  Isolate* isolate = global->GetIsolate();
+  Handle<ScriptContextTable> script_contexts(
+      global->native_context()->script_context_table());
+
+  Handle<JSObject> script_scope =
+      isolate->factory()->NewJSObject(isolate->object_function());
+
+  for (int context_index = 0; context_index < script_contexts->used();
+       context_index++) {
+    Handle<Context> context =
+        ScriptContextTable::GetContext(script_contexts, context_index);
+    Handle<ScopeInfo> scope_info(ScopeInfo::cast(context->extension()));
+    if (!ScopeInfo::CopyContextLocalsToScopeObject(scope_info, context,
+                                                   script_scope)) {
+      return MaybeHandle<JSObject>();
+    }
+  }
+  return script_scope;
+}
+
+
 MUST_USE_RESULT static MaybeHandle<JSObject> MaterializeLocalScope(
     Isolate* isolate, JavaScriptFrame* frame, int inlined_jsframe_index) {
   FrameInspector frame_inspector(frame, inlined_jsframe_index, isolate);
@@ -997,6 +1020,24 @@ static bool SetBlockContextVariableValue(Handle<Context> block_context,
 }
 
 
+static bool SetScriptVariableValue(Handle<Context> context,
+                                   Handle<String> variable_name,
+                                   Handle<Object> new_value) {
+  Handle<ScriptContextTable> script_contexts(
+      context->global_object()->native_context()->script_context_table());
+  ScriptContextTable::LookupResult lookup_result;
+  if (ScriptContextTable::Lookup(script_contexts, variable_name,
+                                 &lookup_result)) {
+    Handle<Context> script_context = ScriptContextTable::GetContext(
+        script_contexts, lookup_result.context_index);
+    script_context->set(lookup_result.slot_index, *new_value);
+    return true;
+  }
+
+  return false;
+}
+
+
 // Create a plain JSObject which materializes the scope for the specified
 // catch context.
 MUST_USE_RESULT static MaybeHandle<JSObject> MaterializeCatchScope(
@@ -1084,6 +1125,7 @@ class ScopeIterator {
     ScopeTypeClosure,
     ScopeTypeCatch,
     ScopeTypeBlock,
+    ScopeTypeScript,
     ScopeTypeModule
   };
 
@@ -1095,6 +1137,7 @@ class ScopeIterator {
         function_(frame->function()),
         context_(Context::cast(frame->context())),
         nested_scope_chain_(4),
+        seen_script_scope_(false),
         failed_(false) {
     // Catch the case when the debugger stops in an internal function.
     Handle<SharedFunctionInfo> shared_info(function_->shared());
@@ -1186,6 +1229,7 @@ class ScopeIterator {
         inlined_jsframe_index_(0),
         function_(function),
         context_(function->context()),
+        seen_script_scope_(false),
         failed_(false) {
     if (function->IsBuiltin()) {
       context_ = Handle<Context>();
@@ -1210,8 +1254,16 @@ class ScopeIterator {
       context_ = Handle<Context>();
       return;
     }
+    if (scope_type == ScopeTypeScript) seen_script_scope_ = true;
     if (nested_scope_chain_.is_empty()) {
-      context_ = Handle<Context>(context_->previous(), isolate_);
+      if (scope_type == ScopeTypeScript) {
+        if (context_->IsScriptContext()) {
+          context_ = Handle<Context>(context_->previous(), isolate_);
+        }
+        CHECK(context_->IsNativeContext());
+      } else {
+        context_ = Handle<Context>(context_->previous(), isolate_);
+      }
     } else {
       if (nested_scope_chain_.last()->HasContext()) {
         DCHECK(context_->previous() != NULL);
@@ -1235,8 +1287,8 @@ class ScopeIterator {
           DCHECK(context_->IsModuleContext());
           return ScopeTypeModule;
         case SCRIPT_SCOPE:
-          DCHECK(context_->IsNativeContext());
-          return ScopeTypeGlobal;
+          DCHECK(context_->IsScriptContext() || context_->IsNativeContext());
+          return ScopeTypeScript;
         case WITH_SCOPE:
           DCHECK(context_->IsWithContext());
           return ScopeTypeWith;
@@ -1252,7 +1304,9 @@ class ScopeIterator {
     }
     if (context_->IsNativeContext()) {
       DCHECK(context_->global_object()->IsGlobalObject());
-      return ScopeTypeGlobal;
+      // If we are at the native context and have not yet seen script scope,
+      // fake it.
+      return seen_script_scope_ ? ScopeTypeGlobal : ScopeTypeScript;
     }
     if (context_->IsFunctionContext()) {
       return ScopeTypeClosure;
@@ -1266,6 +1320,9 @@ class ScopeIterator {
     if (context_->IsModuleContext()) {
       return ScopeTypeModule;
     }
+    if (context_->IsScriptContext()) {
+      return ScopeTypeScript;
+    }
     DCHECK(context_->IsWithContext());
     return ScopeTypeWith;
   }
@@ -1276,6 +1333,9 @@ class ScopeIterator {
     switch (Type()) {
       case ScopeIterator::ScopeTypeGlobal:
         return Handle<JSObject>(CurrentContext()->global_object());
+      case ScopeIterator::ScopeTypeScript:
+        return MaterializeScriptScope(
+            Handle<GlobalObject>(CurrentContext()->global_object()));
       case ScopeIterator::ScopeTypeLocal:
         // Materialize the content of the local scope into a JSObject.
         DCHECK(nested_scope_chain_.length() == 1);
@@ -1314,6 +1374,9 @@ class ScopeIterator {
       case ScopeIterator::ScopeTypeClosure:
         return SetClosureVariableValue(isolate_, CurrentContext(),
                                        variable_name, new_value);
+      case ScopeIterator::ScopeTypeScript:
+        return SetScriptVariableValue(CurrentContext(), variable_name,
+                                      new_value);
       case ScopeIterator::ScopeTypeBlock:
         return SetBlockContextVariableValue(CurrentContext(), variable_name,
                                             new_value);
@@ -1340,7 +1403,8 @@ class ScopeIterator {
   // be an actual context.
   Handle<Context> CurrentContext() {
     DCHECK(!failed_);
-    if (Type() == ScopeTypeGlobal || nested_scope_chain_.is_empty()) {
+    if (Type() == ScopeTypeGlobal || Type() == ScopeTypeScript ||
+        nested_scope_chain_.is_empty()) {
       return context_;
     } else if (nested_scope_chain_.last()->HasContext()) {
       return context_;
@@ -1397,6 +1461,15 @@ class ScopeIterator {
         }
         break;
 
+      case ScopeIterator::ScopeTypeScript:
+        os << "Script:\n";
+        CurrentContext()
+            ->global_object()
+            ->native_context()
+            ->script_context_table()
+            ->Print(os);
+        break;
+
       default:
         UNREACHABLE();
     }
@@ -1411,6 +1484,7 @@ class ScopeIterator {
   Handle<JSFunction> function_;
   Handle<Context> context_;
   List<Handle<ScopeInfo> > nested_scope_chain_;
+  bool seen_script_scope_;
   bool failed_;
 
   void RetrieveScopeChain(Scope* scope,
@@ -2175,6 +2249,7 @@ RUNTIME_FUNCTION(Runtime_DebugEvaluate) {
   // We iterate to find the function's context. If the function has no
   // context-allocated variables, we iterate until we hit the outer context.
   while (!function_context->IsFunctionContext() &&
+         !function_context->IsScriptContext() &&
          !function_context.is_identical_to(outer_context)) {
     inner_context = function_context;
     function_context = Handle<Context>(function_context->previous(), isolate);

test/cctest/test-debug.cc

@@ -7630,9 +7630,25 @@ static void DebugHarmonyScopingListener(
   char script[128];
   i::Vector<char> script_vector(script, sizeof(script));
   SNPrintF(script_vector, "%%GetFrameCount(%d)", break_id);
-  v8::Local<v8::Value> result = CompileRun(script);
+  ExpectInt32(script, 1);
+
+  SNPrintF(script_vector, "var frame = new FrameMirror(%d, 0);", break_id);
+  CompileRun(script);
+  ExpectInt32("frame.evaluate('x').value_", 1);
+  ExpectInt32("frame.evaluate('y').value_", 2);
+
+  CompileRun("var allScopes = frame.allScopes()");
+  ExpectInt32("allScopes.length", 2);
 
-  CHECK_EQ(1, result->Int32Value());
+  ExpectBoolean("allScopes[0].scopeType() === ScopeType.Script", true);
+
+  ExpectInt32("allScopes[0].scopeObject().value_.x", 1);
+
+  ExpectInt32("allScopes[0].scopeObject().value_.y", 2);
+
+  CompileRun("allScopes[0].setVariableValue('x', 5);");
+  CompileRun("allScopes[0].setVariableValue('y', 6);");
+  ExpectInt32("frame.evaluate('x + y').value_", 11);
 }
 
 
@@ -7648,8 +7664,15 @@ TEST(DebugBreakInLexicalScopes) {
   CompileRun(
       "'use strict';            \n"
       "let x = 1;               \n");
-  CompileRun(
+  ExpectInt32(
       "'use strict';            \n"
-      "let y = 1;               \n"
-      "debugger                 \n");
+      "let y = 2;               \n"
+      "debugger;                \n"
+      "x * y",
+      30);
+  ExpectInt32(
+      "x = 1; y = 2; \n"
+      "debugger;"
+      "x * y",
+      30);
 }

test/mjsunit/debug-evaluate-locals-optimized-double.js

@@ -89,9 +89,10 @@ function listener(event, exec_state, event_data, data) {
           }
 
           // All frames except the bottom one have two scopes.
-          assertEquals(2, frame.scopeCount());
+          assertEquals(3, frame.scopeCount());
           assertEquals(debug.ScopeType.Local, frame.scope(0).scopeType());
-          assertEquals(debug.ScopeType.Global, frame.scope(1).scopeType());
+          assertEquals(debug.ScopeType.Script, frame.scope(1).scopeType());
+          assertEquals(debug.ScopeType.Global, frame.scope(2).scopeType());
 
           Object.keys(expected_locals).forEach(function (name) {
             assertEquals(expected_locals[name],
@@ -134,8 +135,9 @@ function listener(event, exec_state, event_data, data) {
                        frame.evaluate(arguments_sum).value());
         } else {
           // The bottom frame only have the global scope.
-          assertEquals(1, frame.scopeCount());
-          assertEquals(debug.ScopeType.Global, frame.scope(0).scopeType());
+          assertEquals(2, frame.scopeCount());
+          assertEquals(debug.ScopeType.Script, frame.scope(0).scopeType());
+          assertEquals(debug.ScopeType.Global, frame.scope(1).scopeType());
         }
 
         // Check the frame function.

test/mjsunit/debug-evaluate-locals-optimized.js

@@ -79,10 +79,11 @@ function listener(event, exec_state, event_data, data) {
                          frame.argumentValue(j).value());
           }
 
-          // All frames except the bottom one have two scopes.
-          assertEquals(2, frame.scopeCount());
+          // All frames except the bottom one have three scopes.
+          assertEquals(3, frame.scopeCount());
           assertEquals(debug.ScopeType.Local, frame.scope(0).scopeType());
-          assertEquals(debug.ScopeType.Global, frame.scope(1).scopeType());
+          assertEquals(debug.ScopeType.Script, frame.scope(1).scopeType());
+          assertEquals(debug.ScopeType.Global, frame.scope(2).scopeType());
 
           Object.keys(expected_locals).forEach(function (name) {
             assertEquals(expected_locals[name],
@@ -124,9 +125,10 @@ function listener(event, exec_state, event_data, data) {
           assertEquals(expected_args_sum,
                        frame.evaluate(arguments_sum).value());
         } else {
-          // The bottom frame only have the global scope.
-          assertEquals(1, frame.scopeCount());
-          assertEquals(debug.ScopeType.Global, frame.scope(0).scopeType());
+          // The bottom frame only have the script scope and the global scope.
+          assertEquals(2, frame.scopeCount());
+          assertEquals(debug.ScopeType.Script, frame.scope(0).scopeType());
+          assertEquals(debug.ScopeType.Global, frame.scope(1).scopeType());
         }
 
         // Check the frame function.

test/mjsunit/debug-function-scopes.js

@@ -48,7 +48,8 @@ var ScopeType = { Global: 0,
                   With: 2,
                   Closure: 3,
                   Catch: 4,
-                  Block: 5 };
+                  Block: 5,
+                  Script: 6};
 
 var f1 = (function F1(x) {
   function F2(y) {
@@ -68,21 +69,23 @@ var f1 = (function F1(x) {
 
 var mirror = Debug.MakeMirror(f1);
 
-assertEquals(5, mirror.scopeCount());
+assertEquals(6, mirror.scopeCount());
 
 CheckScope(mirror.scope(0), { a: 4, b: 5 }, ScopeType.Closure);
 CheckScope(mirror.scope(1), { w: 5, v: "Capybara" }, ScopeType.With);
 CheckScope(mirror.scope(2), { y: 17, z: 22 }, ScopeType.Closure);
 CheckScope(mirror.scope(3), { x: 5 }, ScopeType.Closure);
-CheckScope(mirror.scope(4), {}, ScopeType.Global);
+CheckScope(mirror.scope(4), {}, ScopeType.Script);
+CheckScope(mirror.scope(5), {}, ScopeType.Global);
 
 var f2 = function() { return 5; }
 
 var mirror = Debug.MakeMirror(f2);
 
-assertEquals(1, mirror.scopeCount());
+assertEquals(2, mirror.scopeCount());
 
-CheckScope(mirror.scope(0), {}, ScopeType.Global);
+CheckScope(mirror.scope(0), {}, ScopeType.Script);
+CheckScope(mirror.scope(1), {}, ScopeType.Global);
 
 var f3 = (function F1(invisible_parameter) {
   var invisible1 = 1;
@@ -99,11 +102,12 @@ var f3 = (function F1(invisible_parameter) {
 
 var mirror = Debug.MakeMirror(f3);
 
-assertEquals(3, mirror.scopeCount());
+assertEquals(4, mirror.scopeCount());
 
 CheckScope(mirror.scope(0), { visible2: 20 }, ScopeType.Closure);
 CheckScope(mirror.scope(1), { visible1: 10 }, ScopeType.Closure);
-CheckScope(mirror.scope(2), {}, ScopeType.Global);
+CheckScope(mirror.scope(2), {}, ScopeType.Script);
+CheckScope(mirror.scope(3), {}, ScopeType.Global);
 
 
 var f4 = (function One() {
@@ -122,11 +126,12 @@ var f4 = (function One() {
 
 var mirror = Debug.MakeMirror(f4);
 
-assertEquals(3, mirror.scopeCount());
+assertEquals(4, mirror.scopeCount());
 
 CheckScope(mirror.scope(0), { e2: "I'm error 2" }, ScopeType.Catch);
 CheckScope(mirror.scope(1), { e1: "I'm error 1" }, ScopeType.Catch);
-CheckScope(mirror.scope(2), {}, ScopeType.Global);
+CheckScope(mirror.scope(2), {}, ScopeType.Script);
+CheckScope(mirror.scope(3), {}, ScopeType.Global);
 
 
 var f5 = (function Raz(p1, p2) {
@@ -141,11 +146,12 @@ var f5 = (function Raz(p1, p2) {
 
 var mirror = Debug.MakeMirror(f5);
 
-assertEquals(3, mirror.scopeCount());
+assertEquals(4, mirror.scopeCount());
 
 CheckScope(mirror.scope(0), { p4: 20, p6: 22 }, ScopeType.Closure);
 CheckScope(mirror.scope(1), { p1: 1 }, ScopeType.Closure);
-CheckScope(mirror.scope(2), {}, ScopeType.Global);
+CheckScope(mirror.scope(2), {}, ScopeType.Script);
+CheckScope(mirror.scope(3), {}, ScopeType.Global);
 
 
 function CheckNoScopeVisible(f) {

test/mjsunit/es6/generators-debug-scopes.js

@@ -97,6 +97,7 @@ function CheckScopeChain(scopes, exec_state) {
     assertEquals(i, response.body.scopes[i].index);
     assertEquals(scopes[i], response.body.scopes[i].type);
     if (scopes[i] == debug.ScopeType.Local ||
+        scopes[i] == debug.ScopeType.Script ||
         scopes[i] == debug.ScopeType.Closure) {
       assertTrue(response.body.scopes[i].object.ref < 0);
     } else {
@@ -159,6 +160,7 @@ function CheckScopeContent(content, number, exec_state) {
   assertEquals(scope.scopeType(), response.body.type);
   assertEquals(number, response.body.index);
   if (scope.scopeType() == debug.ScopeType.Local ||
+      scope.scopeType() == debug.ScopeType.Script ||
       scope.scopeType() == debug.ScopeType.Closure) {
     assertTrue(response.body.object.ref < 0);
   } else {
@@ -178,6 +180,7 @@ RunTest("Local 1",
         [],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({}, 0, exec_state);
         });
@@ -188,6 +191,7 @@ RunTest("Local 2",
         [1],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1}, 0, exec_state);
         });
@@ -198,6 +202,7 @@ RunTest("Local 3",
         [1],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1,x:3}, 0, exec_state);
         });
@@ -208,6 +213,7 @@ RunTest("Local 4",
         [1, 2],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1,b:2,x:3,y:4}, 0, exec_state);
         });
@@ -218,6 +224,7 @@ RunTest("Local 5",
         [],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({}, 0, exec_state);
         });
@@ -228,6 +235,7 @@ RunTest("Local 6",
         [],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({i:5}, 0, exec_state);
         });
@@ -242,6 +250,7 @@ RunTest("Local 7",
         [1, 2],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1,b:2,x:3,y:4,i:5,j:6}, 0, exec_state);
         });
@@ -254,6 +263,7 @@ RunTest("With",
           CheckScopeChain([debug.ScopeType.With,
                            debug.ScopeType.With,
                            debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({}, 0, exec_state);
           CheckScopeContent({}, 1, exec_state);
@@ -267,6 +277,7 @@ RunTest("Closure 1",
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
                            debug.ScopeType.Closure,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1}, 1, exec_state);
         },
@@ -305,6 +316,7 @@ RunTest("The full monty",
                            debug.ScopeType.With,
                            debug.ScopeType.Closure,
                            debug.ScopeType.Closure,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({b:16}, 0, exec_state);
           CheckScopeContent({a:15}, 1, exec_state);
@@ -321,6 +333,7 @@ RunTest("Catch block 1",
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Catch,
                            debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({e:'Exception'}, 0, exec_state);
         });

test/mjsunit/harmony/debug-blockscopes.js

@@ -73,7 +73,7 @@ function BeginTest(name) {
 // Check result of a test.
 function EndTest() {
   assertTrue(listener_called, "listerner not called for " + test_name);
-  assertNull(exception, test_name);
+  assertNull(exception, test_name, exception);
   end_test_count++;
 }
 
@@ -108,6 +108,7 @@ function CheckScopeChain(scopes, exec_state) {
     assertEquals(i, response.body.scopes[i].index);
     assertEquals(scopes[i], response.body.scopes[i].type);
     if (scopes[i] == debug.ScopeType.Local ||
+        scopes[i] == debug.ScopeType.Script ||
         scopes[i] == debug.ScopeType.Closure) {
       assertTrue(response.body.scopes[i].object.ref < 0);
     } else {
@@ -197,6 +198,7 @@ function local_block_1() {
 
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({}, 0, exec_state);
 };
@@ -215,6 +217,7 @@ function local_2(a) {
 
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({a:1}, 0, exec_state);
 };
@@ -232,6 +235,7 @@ function local_3(a) {
 
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({a:1,x:3}, 0, exec_state);
 };
@@ -250,6 +254,7 @@ function local_4(a, b) {
 
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({a:1,b:2,x:3,y:4}, 0, exec_state);
 };
@@ -270,6 +275,7 @@ function local_5(a) {
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:5}, 0, exec_state);
   CheckScopeContent({a:1}, 1, exec_state);
@@ -292,6 +298,7 @@ function local_6(a) {
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:6,y:7}, 0, exec_state);
   CheckScopeContent({a:1}, 1, exec_state);
@@ -315,6 +322,7 @@ function local_7(a) {
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:8}, 0, exec_state);
   CheckScopeContent({a:1}, 1, exec_state);
@@ -344,6 +352,7 @@ listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Local,
                    debug.ScopeType.Block,
                    debug.ScopeType.Closure,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({}, 0, exec_state);
   CheckScopeContent({a:1,x:2,y:3}, 2, exec_state);
@@ -364,6 +373,7 @@ function for_loop_1() {
 listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:'y'}, 0, exec_state);
   // The function scope contains a temporary iteration variable, but it is
@@ -389,6 +399,7 @@ listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Block,
                    debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:3}, 0, exec_state);
   CheckScopeContent({x:'y'}, 1, exec_state);
@@ -413,6 +424,7 @@ listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Block,
                    debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:3}, 0, exec_state);
   CheckScopeContent({x:3}, 1, exec_state);
@@ -437,6 +449,7 @@ listener_delegate = function(exec_state) {
                    debug.ScopeType.Block,
                    debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:5}, 0, exec_state);
   CheckScopeContent({x:3}, 1, exec_state);
@@ -460,6 +473,7 @@ listener_delegate = function(exec_state) {
   CheckScopeChain([debug.ScopeType.Block,
                    debug.ScopeType.Block,
                    debug.ScopeType.Local,
+                   debug.ScopeType.Script,
                    debug.ScopeType.Global], exec_state);
   CheckScopeContent({x:3,y:5}, 0, exec_state);
   CheckScopeContent({x:3,y:5}, 1, exec_state);

test/mjsunit/harmony/debug-function-scopes.js

@@ -28,6 +28,7 @@
 // Flags: --expose-debug-as debug --harmony-scoping
 
 "use strict";
+let top_level_let = 255;
 
 // Get the Debug object exposed from the debug context global object.
 var Debug = debug.Debug;
@@ -50,7 +51,8 @@ var ScopeType = { Global: 0,
                   With: 2,
                   Closure: 3,
                   Catch: 4,
-                  Block: 5 };
+                  Block: 5,
+                  Script: 6};
 
 var f1 = (function F1(x) {
   function F2(y) {
@@ -72,12 +74,13 @@ var f1 = (function F1(x) {
 
 var mirror = Debug.MakeMirror(f1);
 
-assertEquals(4, mirror.scopeCount());
+assertEquals(5, mirror.scopeCount());
 
 CheckScope(mirror.scope(0), { a: 4, b: 5 }, ScopeType.Closure);
 CheckScope(mirror.scope(1), { z: 22, w: 5, v: "Capybara" }, ScopeType.Closure);
 CheckScope(mirror.scope(2), { x: 5 }, ScopeType.Closure);
-CheckScope(mirror.scope(3), {}, ScopeType.Global);
+CheckScope(mirror.scope(3), { top_level_let: 255 }, ScopeType.Script);
+CheckScope(mirror.scope(4), {}, ScopeType.Global);
 
 var f2 = (function() {
   var v1 = 3;
@@ -104,7 +107,7 @@ var f2 = (function() {
 
 var mirror = Debug.MakeMirror(f2);
 
-assertEquals(5, mirror.scopeCount());
+assertEquals(6, mirror.scopeCount());
 
 // Implementation artifact: l4 isn't used in closure, but still it is saved.
 CheckScope(mirror.scope(0), { l4: 11 }, ScopeType.Block);
@@ -112,4 +115,5 @@ CheckScope(mirror.scope(0), { l4: 11 }, ScopeType.Block);
 CheckScope(mirror.scope(1), { l3: 9 }, ScopeType.Block);
 CheckScope(mirror.scope(2), { l1: 6, l2: 7 }, ScopeType.Block);
 CheckScope(mirror.scope(3), { v1:3, l0: 0, v3: 5, v6: 11 }, ScopeType.Closure);
-CheckScope(mirror.scope(4), {}, ScopeType.Global);
+CheckScope(mirror.scope(4), { top_level_let: 255 }, ScopeType.Script);
+CheckScope(mirror.scope(5), {}, ScopeType.Global);