' Gambas class file

''' Low-level class for planning and printing test results in Test Anything Protocol ([TAP]) format.
''' 
''' [TAP]: http://testanything.org/tap-specification.html

Event Filter

Property {Output} As Stream Use $hOutput
Property Read Session As TapContext

Property Line As String Use $sLine

Private $aSubtests As New TapContext[]
Private $hCurrent As New TapContext

Public Sub _new(Optional Tests As Integer, Optional Comment As String, Optional {Output} As Stream = File.Out)

    $hOutput = {Output}
    With $hCurrent
        .Plan = Test.NO_PLAN
        .TestsRun = 0
        .LastId = 0
        .Finished = False
    End With
    If Not IsMissing(Tests) Then Plan(Tests, Comment)

End

Public Sub Subtest(Description As String, Optional Tests As Integer, Optional Comment As String)

    $aSubtests.Push($hCurrent)
    With $hCurrent = New TapContext
        .Summary.Description = Description
        .Summary.Comment = Comment
        .Plan = Test.NO_PLAN
        .TestsRun = 0
        .LastId = 0
        .Finished = False
    End With
    If Tests Then Plan(Tests)

End

Public Sub Plan(Tests As Integer, Optional Comment As String)

    With $hCurrent
        If .Finished Or .SkipAll Then Error.Raise(("Tests already finished"))
        If .TestsRun Then Error.Raise(Subst$(("Too late to plan. Already ran &1 tests"), .TestsRun))
        ' TAP specification lists '1..0 # Skipped: WWW::Mechanize not installed'
        ' as a valid example.
        If Tests <= Test.NO_PLAN Then Error.Raise(("Number of tests must be non-negative"))
        .Plan = Tests
    End With
    Print(Subst$("1..&1&2", Tests, IIf(Comment, " # " & Comment, "")))

End

Public Sub SkipAll(Optional Comment As String)

    Plan(0, "SKIP" & IIf(Comment, " ", "") & Comment)
    $hCurrent.SkipAll = True

End

Public Sub Finish()

    Dim hFinished As TapContext

    With $hCurrent
        Dim hTest As TestAssertion

        If .Finished Then Error.Raise(("Tests already finished"))

        ' Print a plan line after the fact
        If .Plan = Test.NO_PLAN Then
            .Plan = .TestsRun
            Print("1.." & .Plan)
        Endif

        ' Sum up this subtest
        .Finished = True
        .Summary.Ok = (.Plan > 0 Or .SkipAll) And (.TestsRun = .Plan)
        For Each hTest In .Summary.Subtests
            .Summary.Ok = .Summary.Ok And hTest.Success
        Next
    End With

    ' Go one level up if possible. Unless we are the top-level test,
    ' we add one assertion for this finishing subtest.
    hFinished = $hCurrent
    Try $hCurrent = $aSubtests.Pop()
    If Not Error Then
        Assert(hFinished.Summary)
    Endif

End

Public Sub Assert(Assertion As TestAssertion) As TestAssertion

    Dim sDirective As String
    Dim sLine As String

    With Assertion
        If $hCurrent.Finished Or $hCurrent.SkipAll Then Error.Raise(("Tests already finished"))

        ' It is not advised to start a description with a number token because
        ' it will be interpreted as the (optional) test ID. We issue a warning
        ' about this but fix it anyway by always printing the ID before *and*
        ' prefixing the Description with a dash, as is common.
        If .Description Match "^[0-9]+(\\s|$)" Then
            Error Subst$(("Warning: Description '&1' should not start with a number"), .Description)
        Endif
        If .Description Like "*#*" Then
            Error.Raise(Subst$(("Description '&1' may not contain a '#' character"), .Description))
        Endif

        Inc $hCurrent.TestsRun
        If Not .Id Then .Id = $hCurrent.TestsRun
        $hCurrent.LastId = .Id
        sLine = Subst$("&1 &2 - &3", IIf(.Ok, "ok", "not ok"), .Id, .Description)

        If .Directive <> TestAssertion.NONE Then
            ' Matches the values of the Enum TestAssertion.TODO, TestAssertion.SKIP
            sDirective = Choose(.Directive, "TODO", "SKIP")
            If Not sDirective Then Error.Raise(Subst$(("Unsupported directive '&1'"), .Directive))
            sLine &= " # " & sDirective
            If .Comment Then sLine &= " " & .Comment
        Endif
    End With

    Print(sLine)
    $hCurrent.Summary.Subtests.Push(Assertion)
    Return Assertion

End

'' Unwinds the subtest stack. BailOut will always bail out of all the subtests.
Private Sub Unwind()

    While $aSubtests.Count > 0
        Note("Unwinding subtest stack!")
        Finish()
    Wend

End

Public Sub BailOut(Optional Comment As String)

    Unwind()
    'The string "Bail out!" must not be changed!
    Print("Bail out!" & IIf(Comment, " " & Comment, ""))
    $hCurrent.Finished = True

End

Public Sub Diagnostic(Comment As String)

    Dim sLine As String

    ' Split on these doesn't do what I mean: on the empty string, we get
    ' zero lines, on a newline we get two. I want one in both cases.
    If Not Comment Or If Comment = gb.Lf Then
        Print("#")
        Return
    Endif

    For Each sLine In Split(Comment, "\n")
        Print("# " & sLine)
    Next

End

Public Sub Note(Comment As String)

    Diagnostic(Comment)

End

Public Sub Print({Line} As String)

    Dim bCancel As Boolean

    $sLine = {Line}
    bCancel = Raise Filter
    If bCancel Then Return
    '    Print #$hOutput, String$($aSubtests.Count, "\t"); $sLine
    
    Print #$hOutput, String$($aSubtests.Count, "  "); $sLine
    Flush #$hOutput

End

Private Function Session_Read() As TapContext

    If $aSubtests.Count Then Return $aSubtests[0]
    Return $hCurrent

End