frog: check that const constructors have potentially const initializers. Also

frog/member.dart

Index: frog/member.dart
diff --git a/frog/member.dart b/frog/member.dart
index f9f9d3a57f49bfc0a71abb464e4110c24d5c9731..d6b1b7d9a64837683e7cf7d27efc0ca4e58f1fd1 100644
--- a/frog/member.dart
+++ b/frog/member.dart
@@ -1143,6 +1143,10 @@ class MethodMember extends Member {
           var x = assign.x; // DotExpression or VarExpression
           var fname = x.name.name;
           var val = generator.visitValue(assign.y);
+          if (!val.isConst) {
+            world.error('invalid non-const initializer in const constructor',
+                assign.y.span);

[jimhug, 2011/12/12 18:14:30]

Could this be val.span instead?  It doesn't really matter right now, I'm just
thinking a little ahead to richer Values and more analysis with them.

[Siggi Cherem (dart-lang), 2011/12/12 18:20:55]

For some reason in this case they are not the same - we need to look more into
it. In the new test, assing.y.span is the whole expression "1.toString()", but
val.span is just the method call portion ("toString").

+          }
           fields[fname] = val;
         }
       }
@@ -1152,9 +1156,14 @@ class MethodMember extends Member {
 
     // Add default values only if they weren't overriden in the constructor.
     for (var f in declaringType.members.getValues()) {
-      if (f is FieldMember && !f.isStatic && f.value != null
-          && !fields.containsKey(f.name)) {
-        fields[f.name] = f.computeValue();
+      if (f is FieldMember && !f.isStatic && !fields.containsKey(f.name)) {
+        if (!f.isFinal) {
+          world.error('const class "${declaringType.name}" has non-final '
+              + 'field "${f.name}"', f.span);
+        }
+        if (f.value != null) {
+          fields[f.name] = f.computeValue();
+        }
       }
     }