The expected error can only be 440 / Automation error?

Question

Context

I wrote a small testing library in VBA, so I can write unit tests as follows:

'@ExpectedError()
Public Sub TestCannotRegisterLoggerTwice()

    Dim logger As ILogger
    Set logger = MockLogger.Create("TestLogger", TraceLevel)

    LogManager.Register logger
    LogManager.Register logger

End Sub

The above test passes:

2014-10-04 16:42:55 TestCannotRegisterLoggerTwice: [PASS]

And if I remove the attribute ExpectedError, this will not work:

2014-10-04 16:43:49 TestCannotRegisterLoggerTwice: [INCONCLUSIVE] - Test raised an error: Automation error

So far so good. Almost.

---

Testing errors work fine!

Now, if I do the test, drop the division by zero, for example:

'@ExpectedError()
Public Sub TestCannotRegisterLoggerTwice()

    Dim logger As ILogger
    Set logger = MockLogger.Create("TestLogger", TraceLevel)

    Dim boom As Integer
    boom = 1 / 0

    LogManager.Register logger
    LogManager.Register logger

End Sub

The test is still unconvincing, but this time the error was correctly raised:

2014-10-04 16:45:12 TestCannotRegisterLoggerTwice: [INCONCLUSIVE] - Test raised an error: Division by zero

The part that I don’t understand is that in both cases the error occurs in the same VBAProject - the first in the class called LogManager(SUT), the last in the class called LogManagerTests.

Here is the part that causes the expected error that I am testing for:

Public Sub Register(ByVal logger As ILogger)
    If Not this.Loggers.Exists(logger.Name) Then
        this.Loggers.Add logger.Name, logger
    Else
        Err.Raise LogManagerError.DuplicateLoggerError, "LogManager.Register", "There is already a logger registered with name '" & logger.Name & "'."
    End If
End Sub

---

What I want

'@ExpectedError(-2147220406) (Long LogManagerError.DuplicateLoggerError) TestEngine.ReflectTestMethods:

For Each prospect In classMethods

    If CanAddTestMethod(prospect, result) Then

        Set tMethod = New TestMethod
        Set tMethod.OwnerInstance = classInstance
        tMethod.MethodName = prospect.name

        If prospect.HasAttribute(ExpectedErrorAttribute) Then
            If prospect.AttributeParameters(ExpectedErrorAttribute).Count <> 0 Then
                Err.Raise vbObjectError + 1055, "TestEngine.ReflectTestMethods", "ExpectedErrorAttribute for test method '" & prospect.name & "' should not have parameters."
            End If

            'force an "Automation Error" to be expected, 
            'because VBA "eats" the expected error thrown in the SUT:
            tMethod.ExpectedError = 440 ' prospect.AttributeParameters(ExpectedErrorAttribute).First

        End If

        result.Add tMethod.MethodName, tMethod

    End If

Next

? , SUT ?

---

-,

, ​​ , :

'@ExpectedError()
Public Sub TestCannotRegisterLoggerTwice()

    On Error GoTo CleanFail

    Dim logger As ILogger
    Set logger = MockLogger.Create("TestLogger", TraceLevel)

    LogManager.Register logger
    LogManager.Register logger

    Exit Sub

CleanFail:

    Dim errNumber As Long
    errNumber = Err.Number

    Dim errSource As String
    errSource = Err.Source

    Dim errDescription As String
    errDescription = Err.Description

    Err.Raise errNumber, errSource, errDescription
End Sub

errDescription / , - Automation 440.

---

, ?

EDIT: , "" , :

'@ExpectedError(5)
Public Sub TestCannotRegisterLoggerTwice()

    Dim logger As ILogger
    Set logger = MockLogger.Create("TestLogger", TraceLevel)

    LogManager.Register logger
    LogManager.Register logger

End Sub

... , TestEngine, @ExpectedError, # 5/ " " SUT ; . , SUT , .

VBA?

Answer 1

, VBA.

, SUT, vbObjectError + n ( -2147220406 , ), , "":

Public Enum LogManagerError
    DuplicateLoggerError = 100
    LoggerNotRegisteredError
End Enum

TestEngine "" , :

'@ExpectedError(100)
Public Sub TestCannotRegisterLoggerTwice()

    Dim logger As ILogger
    Set logger = MockLogger.Create("TestLogger", TraceLevel)

    LogManager.Register logger
    LogManager.Register logger

End Sub

:

2014-10-04 18:09:56 TestCannotRegisterLoggerTwice: [PASS]

ExpectedError , :

2014-10-04 18:10:20 TestCannotRegisterLoggerTwice: [INCONCLUSIVE] - Test raised an error: Application-defined or object-defined error

- , , , .

, SUT , , , , .

"" :

'@ExpectedError(100)
Public Sub TestCannotRegisterLoggerTwice()

    On Error GoTo CleanFail

    Dim logger As ILogger
    Set logger = MockLogger.Create("TestLogger", TraceLevel)

    LogManager.Register logger
    LogManager.Register logger

    Exit Sub
CleanFail:
    MsgBox Err.Description
    Err.Raise Err.Number

End Sub

2014-10-04 18:21:24 TestCannotRegisterLoggerTwice: [PASS]