anchor.diff:  
   /// Compute the path to the file into which documentation is being generated.
   String computeOutputPath() {
  -  Context pathContext = PhysicalResourceProvider.INSTANCE.pathContext;
  -  String packageRoot = pathContext.normalize(package_root.packageRoot);
  -  String analyzerPath = pathContext.join(packageRoot, 'analyzer');
  +  var pathContext = PhysicalResourceProvider.INSTANCE.pathContext;
  +  var packageRoot = pathContext.normalize(package_root.packageRoot);
  +  var analyzerPath = pathContext.join(packageRoot, 'analyzer');
     return pathContext.join(
         analyzerPath, 'tool', 'diagnostics', 'diagnostics.md');
   }
  
positive.code:         _extractAllDocs(
              errorClass.name, cfeToAnalyzerErrorCodeTables.analyzerCodeToInfo);
          // Note: only one error class has the `includeCfeMessages` flag set;
          // verify_diagnostics_test.dart verifies this.  So we can safely break.
          break;
        }
      }
  
negative.code: [meta-visibleForOverriding]: https://pub.dev/documentation/meta/latest/meta/visibleForOverriding-constant.html
  [meta-visibleForTesting]: https://pub.dev/documentation/meta/latest/meta/visibleForTesting-constant.html
  ''');
      var errorCodes = infoByName.keys.toList();
      errorCodes.sort();
      for (String errorCode in errorCodes) {
        var info = infoByName[errorCode]!;
        if (info.hasDocumentation) {
          sink.writeln();
          info.writeOn(sink);
  