Debugger: Save/restore expression node values.

- This allows expression results to be highlighted for value changes
  as we already do for regular variable values.

src/apps/debugger/user_interface/gui/team_window/VariablesView.cpp

@@ -2470,6 +2470,14 @@ VariablesView::_SaveViewState() const
 	if (values->Init() != B_OK)
 		return;
 
+	ExpressionValues* expressionValues = new(std::nothrow) ExpressionValues;
+	if (expressionValues == NULL)
+		return;
+	BReference<ExpressionValues> expressionReference(expressionValues, true);
+
+	if (expressionValues->Init() != B_OK)
+		return;
+
 	// create an empty view state
 	VariablesViewState* viewState = new(std::nothrow) VariablesViewState;
 	if (viewState == NULL)
@@ -2480,6 +2488,7 @@ VariablesView::_SaveViewState() const
 		return;
 
 	viewState->SetValues(values);
+	viewState->SetExpressionValues(expressionValues);
 
 	// populate it
 	TreeTablePath path;
@@ -2546,20 +2555,16 @@ VariablesView::_AddViewStateDescendentNodeInfos(VariablesViewState* viewState,
 				nodeInfo.SetRendererSettings(settings->Message());
 		}
 
+		Value* value = node->GetValue();
 		Variable* variable = node->GetVariable();
-		if (variable == NULL) {
+		if (variable != NULL) {
-			// ignore synthetic nodes
-			continue;
-		}
-
-		ObjectID* id = variable->ID();
 			TypeComponentPath* componentPath = node->GetPath();
+			ObjectID* id = variable->ID();
 
 			status_t error = viewState->SetNodeInfo(id, componentPath, nodeInfo);
 			if (error != B_OK)
 				return error;
 
-		Value* value = node->GetValue();
 			if (value != NULL) {
 				BVariant variableValueData;
 				if (value->ToVariant(variableValueData))
@@ -2573,6 +2578,24 @@ VariablesView::_AddViewStateDescendentNodeInfos(VariablesViewState* viewState,
 			error = _AddViewStateDescendentNodeInfos(viewState, node, path);
 			if (error != B_OK)
 				return error;
+		} else {
+			ExpressionValueNodeChild* child
+				= dynamic_cast<ExpressionValueNodeChild*>(node->NodeChild());
+			if (child != NULL && value != NULL) {
+				BVariant variableValueData;
+				if (value->ToVariant(variableValueData)) {
+					FunctionID* id = fStackFrame->Function()->GetFunctionID();
+					if (id == NULL)
+						return B_NO_MEMORY;
+					BReference<FunctionID> functionReference(id, true);
+					status_t error = viewState->GetExpressionValues()
+						->SetValue(id, fThread, child->GetExpression(),
+						variableValueData);
+					if (error != B_OK)
+						return error;
+				}
+			}
+		}
 
 		path.RemoveLastComponent();
 	}
@@ -2593,10 +2616,7 @@ VariablesView::_ApplyViewStateDescendentNodeInfos(VariablesViewState* viewState,
 
 		// apply the node's info, if any
 		Variable* variable = node->GetVariable();
-		if (variable == NULL) {
+		if (variable != NULL) {
-			// ignore synthetic nodes
-			return B_OK;
-		}
 			ObjectID* objectID = node->GetVariable()->ID();
 			TypeComponentPath* componentPath = node->GetPath();
 			const VariablesViewNodeInfo* nodeInfo = viewState->GetNodeInfo(
@@ -2604,8 +2624,8 @@ VariablesView::_ApplyViewStateDescendentNodeInfos(VariablesViewState* viewState,
 			if (nodeInfo != NULL) {
 				// NB: if the node info indicates that the node in question
 				// was being cast to a different type, this *must* be applied
-			// before any other view state restoration, since it potentially
+				// before any other view state restoration, since it
-			// changes the child hierarchy under that node.
+				// potentially changes the child hierarchy under that node.
 				Type* type = nodeInfo->GetCastedType();
 				if (type != NULL) {
 					ValueNode* valueNode = NULL;
@@ -2621,20 +2641,36 @@ VariablesView::_ApplyViewStateDescendentNodeInfos(VariablesViewState* viewState,
 				// apply them once the value is retrieved.
 				node->SetLastRendererSettings(nodeInfo->GetRendererSettings());
 
-			fVariableTable->SetNodeExpanded(path, nodeInfo->IsNodeExpanded());
+				fVariableTable->SetNodeExpanded(path,
+					nodeInfo->IsNodeExpanded());
 
 				BVariant previousValue;
 				if (viewState->Values()->GetValue(objectID, componentPath,
 					previousValue)) {
 					node->SetPreviousValue(previousValue);
 				}
+			}
+		} else {
+			ExpressionValueNodeChild* child
+				= dynamic_cast<ExpressionValueNodeChild*>(node->NodeChild());
+			if (child != NULL) {
+				BVariant previousValue;
+				FunctionID* id = fStackFrame->Function()->GetFunctionID();
+				if (id == NULL)
+					return B_NO_MEMORY;
+				BReference<FunctionID> idReference(id, true);
+				if (viewState->GetExpressionValues()->GetValue(id, fThread,
+					child->GetExpression(), previousValue)) {
+					node->SetPreviousValue(previousValue);
+				}
+			}
+		}
 
 		// recurse
 		status_t error = _ApplyViewStateDescendentNodeInfos(viewState, node,
 			path);
 		if (error != B_OK)
 			return error;
-		}
 
 		path.RemoveLastComponent();
 	}