Delphi單元測試：為CUT編寫一個簡單的間諜

Question

我正在尋找一種簡便 ， 簡潔地為Delphi下的DUnitX測試框架編寫間諜的方法。

過去，我使用過非常丑陋的方法：

[TestFixture]
Test = class(TObject)
public
  [test]
  procedure Test1;
end;

TMyClass = class(TObject)
protected
  procedure MyProcedure; virtual;
end;

TMyTestClass = class(TMyClass)
protected
  fMyProcedureCalled : Boolean;
  procedure MyProcedure; override;
end

procedure TMyTestClass.MyProcedure;
begin
   fMyProcedureCalled := true;
   inherited;
end;

procedure Test.Test1;
var aObj : TMyTestClass;
begin
   TMyTestClass.Create;
   Assert.IsTrue(aObj.fMyProcedureCalled);
end;

所有這些代碼可檢查是否調用了過程。 太冗長了！

有沒有辦法寫間諜來幫助我減少代碼？

Answer 1

聽起來像是一個模擬的用例（我在這里使用了模擬一詞，因為大多數框架將它們的各種測試雙精度模型稱為模擬）。

在下面的示例中，我使用的是DUnit，但對於DUnitX來說應該沒有任何區別。 我也在使用Spring4D 1.2中的模擬功能（我沒有檢查Delphi Mocks是否支持此功能）

unit MyClass;

interface

type
  TMyClass = class
  private
    fCounter: Integer;
  protected
    procedure MyProcedure; virtual;
  public
    property Counter: Integer read fCounter;
  end;

implementation

procedure TMyClass.MyProcedure;
begin
  Inc(fCounter);
end;

end.

program Tests;

uses
  TestFramework,
  TestInsight.DUnit,
  Spring.Mocking,
  MyClass in 'MyClass.pas';

type
  TMyClass = class(MyClass.TMyClass)
  public
    // just to make it accessible for the test
    procedure MyProcedure; override;
  end;

  TMyTest = class(TTestCase)
  published
    procedure Test1;
  end;

procedure TMyClass.MyProcedure;
begin
  inherited;
end;

procedure TMyTest.Test1;
var
  // the mock is getting auto initialized on its first use
  // and defaults to TMockBehavior.Dynamic which means it lets all calls happen
  m: Mock<TMyClass>;
  o: TMyClass;
begin
  // set this to true to actually call the "real" method
  m.CallBase := True;
  // do something with o
  o := m;
  o.MyProcedure;

  // check if the expected call actually did happen
  m.Received(Times.Once).MyProcedure;

  // to prove that it actually did call the "real" method
  CheckEquals(1, o.Counter);
end;

begin
  RegisterTest(TMyTest.Suite);
  RunRegisteredTests();
end.

請記住，盡管這僅適用於虛擬方法。