anchor.diff:      TranslateUri uriTranslator = await TranslateUri.parse(packages);
       bool strongMode = environment.containsKey(STRONG_MODE);
       bool updateExpectations = environment["updateExpectations"] == "true";
  +    bool updateComments = environment["updateComments"] == "true";
       String astKindString = environment[AST_KIND_INDEX];
       AstKind astKind =
           astKindString == null ? null : AstKind.values[int.parse(astKindString)];
  -    return new FastaContext(vm, strongMode, updateExpectations, uriTranslator,
  -        environment.containsKey(ENABLE_FULL_COMPILE), astKind);
  +    return new FastaContext(vm, strongMode, updateExpectations, updateComments,
  +        uriTranslator, environment.containsKey(ENABLE_FULL_COMPILE), astKind);
     }
   }
   
  
positive.code:         p = await sourceTarget.writeProgram(null);
          instrumentation?.finish();
          if (instrumentation != null && instrumentation.hasProblems) {
            if (updateExpectations) {
              await instrumentation.fixSource(description.uri);
            } else {
              return fail(null, instrumentation.problemsAsString);
  
negative.code:   final bool strongMode;
  
    const Outline(this.fullCompile, this.astKind, this.strongMode,
        {this.updateComments: false});
  
    final bool updateComments;
  
    String get name {
      return fullCompile ? "${astKind} compile" : "outline";
  