VM: Fix issue with local variable values reported by the debugger.

tests/standalone/debugger/debug_lib.dart

Index: tests/standalone/debugger/debug_lib.dart
===================================================================
--- tests/standalone/debugger/debug_lib.dart	(revision 43843)
+++ tests/standalone/debugger/debug_lib.dart	(working copy)
@@ -299,8 +299,9 @@
 
 class LocalsMatcher extends Command {
   Map locals = {};
+  int frame_index;
 
-  LocalsMatcher(this.locals) {
+  LocalsMatcher(this.locals, this.frame_index) {
     template = {"id": 0, "command": "getStackTrace", "params": {"isolateId": 0}};
   }
 
@@ -310,8 +311,8 @@
     List frames = getJsonValue(debugger.currentMessage, "result:callFrames");
     assert(frames != null);
 
-    String functionName = frames[0]['functionName'];
-    List localsList = frames[0]['locals'];
+    String functionName = frames[frame_index]['functionName'];
+    List localsList = frames[frame_index]['locals'];
     Map reportedLocals = {};
     localsList.forEach((local) => reportedLocals[local['name']] = local['value']);
     for (String key in locals.keys) {
@@ -333,11 +334,47 @@
 }
 
 
-MatchLocals(Map localValues) {
-  return new LocalsMatcher(localValues);
+MatchLocals(Map localValues, [int frame_index = 0]) {

[hausner, 2015/02/18 18:32:29]

It doesn't look like you are using MatchLocals with a frame index anywhere. It's
nice to have this functionality, but for consistency I would prefer if the
frame_index was the first parameter, like in MatchFrame above. Since you are not
using it now, you could just remove the second parameter so you don't have to
fix the other tests.

[Florian Schneider, 2015/02/18 18:45:23]

Yes, I only used to while testing. I'll remove it for now.

+  return new LocalsMatcher(localValues, frame_index);
 }
 
 
+class InvertedLocalsMatcher extends Command {

[hausner, 2015/02/18 18:32:28]

Would you mind adding a one-liner comment what this matcher is good for? It
seems less intuitive than other matcher names.

[Florian Schneider, 2015/02/18 18:45:23]

Added comment and renamed to AssertLocalsNotVisibleMatcher - I could not find a
different descriptive short name.

+  List<String> locals;
+  int frame_index;
+
+  InvertedLocalsMatcher(this.locals, this.frame_index) {
+    template = {"id": 0, "command": "getStackTrace", "params": {"isolateId": 0}};
+  }
+
+  void matchResponse(Debugger debugger) {
+    super.matchResponse(debugger);
+
+    List frames = getJsonValue(debugger.currentMessage, "result:callFrames");
+    assert(frames != null);
+
+    String functionName = frames[frame_index]['functionName'];
+    List localsList = frames[frame_index]['locals'];
+    Map reportedLocals = {};
+    localsList.forEach((local) => reportedLocals[local['name']] = local['value']);
+    for (String key in locals) {
+      if (reportedLocals[key] != null) {
+        debugger.error("Error in $functionName(): local variable $key not "
+                       "expected in scope (reported value "
+                       "${reportedLocals[key]['text']})");
+        return;
+      }
+    }
+    print("Matched locals $locals");
+  }
+}
+
+
+AssertLocalsNotVisible(List<String> locals, [int frame_index = 0]) {
+  return new InvertedLocalsMatcher(locals, frame_index);
+}
+
+
 class EventMatcher {
   String eventName;
   Map params;