What is the reason for this code in TTestDataProvider.GetProvider?

[Uwe Raabe 1871]

The current implementation of one overload of TTestDataProvider.GetProvider looks like this:

class function TestDataProviderManager.GetProvider(const AClass: TTestDataProviderClass) : ITestDataProvider;
var
  key : string;
begin
  result := nil;
  if (FList.ContainsValue(AClass)) then
  begin
    for key in flist.keys do
    begin
      if (flist[key] = AClass) then
      begin
        result := TTestDataProviderClass(flist[key]).Create;
        break;
      end;
    end;
  end;
end;

Is there any reason why that cannot be written as:

class function TestDataProviderManager.GetProvider(const AClass: TTestDataProviderClass) : ITestDataProvider;
begin
  result := AClass.Create;
end;

With that one could avoid registering the provider.

 

The reasoning for my question is, that I have a base provider class and several derived classes to overcome the lack of ability to parametrize a data provider instance. All these derived classes are local to one test unit and I would like all of them to have the same class name. Unfortunately the registration requires me to give distinct names for them and you know - naming is hard. Just declaring the derived class and use that in a TestCaseProvider attribute would simplify this a lot.

 

Concrete: TTestDataFilesProvider provides a list of files, but requires the path and search pattern as parameters. Now I derive individual classes (with fixed values) immediately before they are used.