Unit refuses to get Invulnerable

scope SodeNoShirayuki initializer In_Sode_no_Shirayuki

globals
    private constant integer SS = 'A04L'
    private constant integer RANGE = 512
    private constant string MESSAGE_BEGIN = "Mae, Sode no Shirayuki!"
    private constant string MESSAGE_FINISH = "Some no mai, Tsukishiro!"
    private real TreeX
    private real TreeY
endglobals

private struct SNS
    unit caster
    real damage
    real x
    real y
    integer level
    weathereffect we
    rect r
endstruct

private function Sode_no_Shirayuki_Conditions takes nothing returns boolean
    return (GetSpellAbilityId() == SS)
endfunction

private function Sode_no_Shirayuki_Trees takes nothing returns nothing
    local destructable tree = GetEnumDestructable()
    local real x
    local real y
    local real dist
    if IsDestructableTree(tree) then
        set x = GetDestructableX(tree)
        set y = GetDestructableY(tree)
        set x = x - TreeX
        set y = y - TreeY
        set dist = SquareRoot(x * x + y * y)
        if (dist <= RANGE) then
            call KillDestructable(tree)
            set tree = null
        endif
    endif
endfunction

private function Sode_no_Shirayuki_Weather takes nothing returns nothing
    local SNS s = GetTimerData(GetExpiredTimer())
    call RemoveRect(s.r)
    call RemoveWeatherEffect(s.we)
    set s.we = null
    call ReleaseTimer(GetExpiredTimer())
    call s.destroy()
endfunction

private function Sode_no_Shirayuki_Run takes nothing returns nothing
    local SNS s = GetTimerData(GetExpiredTimer())
    local group tg
    local unit tempunit
    local unit dummy
    local player tp
    
    call DisplayText(s.caster, MESSAGE_FINISH, 1)
    call SetUnitAnimation(s.caster, "Attack")
    if (GetUnitCurrentOrder(s.caster) == 852195) then
            set tp = GetOwningPlayer(s.caster)
            set tg = CreateGroup()
            call GroupEnumUnitsInRange(tg, s.x, s.y, RANGE, null)
            set dummy = CreateUnit(tp, 'h019', s.x, s.y, 0)
            call UnitApplyTimedLife(dummy, 'BTLF', 2.00)
            call SetUnitVertexColor(dummy, 255, 255, 255, 200)
            loop
                set tempunit = FirstOfGroup(tg)
                exitwhen tempunit == null
                if TargetCheck(s.caster, tempunit) then
                    call UnitDamageTargetEx(s.caster, tempunit, s.damage, ATTACK_TYPE_NORMAL, DAMAGE_TYPE_SPELL, false, true)
                    set dummy = CreateUnit(tp, 'h00B', s.x, s.y, 0)
                    call UnitAddAbility(dummy, 'A04M')
                    call SetUnitAbilityLevel(dummy, 'A04M', (4 + s.level * 2))
                    call IssueTargetOrder(dummy, "thunderbolt", tempunit)
                    call UnitApplyTimedLife(dummy, 'BTLF', 1.00)
                endif
                call GroupRemoveUnit(tg, tempunit)
            endloop
            set dummy = null
    endif
    
    set TreeX = s.x
    set TreeY = s.y
    call EnumDestructablesInRect(s.r, null, function Sode_no_Shirayuki_Trees)
    
    call UnitRemoveAbility(s.caster, 'Avul')
    set s.caster = null
    set tp = null
    call TimerStart(GetExpiredTimer(), 1, false, function Sode_no_Shirayuki_Weather)
endfunction

private function Sode_no_Shirayuki_Actions takes nothing returns nothing
    local SNS s = SNS.create()
    local timer t = NewTimer()
    local unit dummy
    set s.caster = GetTriggerUnit()
    set s.level = GetUnitAbilityLevel(s.caster, SS)
    set s.x = GetSpellTargetX()
    set s.y = GetSpellTargetY()
    call SetUnitPosition(s.caster, s.x, s.y)
    set s.x = GetUnitX(s.caster)
    set s.y = GetUnitY(s.caster)
    set s.damage = (s.level * 100) + GetHeroInt(s.caster, true)
    
    call DisplayText(s.caster, MESSAGE_BEGIN, 1)
    call UnitAddAbility(s.caster, 'Avul')
    set dummy = CreateUnit(GetOwningPlayer(s.caster), 'h018', s.x, s.y, 0)
    call UnitApplyTimedLife(dummy, 'BTLF', 1.50)
    set dummy = null
    set s.r = Rect(s.x-512, s.y-512, s.x+512, s.y+512)
    set s.we = AddWeatherEffect(s.r, 'SNhs')
    call EnableWeatherEffect(s.we, true)
    call SetTimerData(t,s)
    call TimerStart(t, 2, false, function Sode_no_Shirayuki_Run)
endfunction

//===========================================================================
private function In_Sode_no_Shirayuki takes nothing returns nothing
    local trigger t_Sode_no_Shirayuki = CreateTrigger()
    call TriggerRegisterAnyUnitEventBJ( t_Sode_no_Shirayuki, EVENT_PLAYER_UNIT_SPELL_EFFECT )
    call TriggerAddCondition( t_Sode_no_Shirayuki, Condition( function Sode_no_Shirayuki_Conditions ) )
    call TriggerAddAction( t_Sode_no_Shirayuki, function Sode_no_Shirayuki_Actions )
    set t_Sode_no_Shirayuki = null
endfunction

endscope

library InvulnerabilityTest initializer init
    
    private function init takes nothing returns nothing
        local unit u = CreateUnit(Player(0),'hfoo',0,0,270)
        call SetUnitInvulnerable(u,true)
        if GetUnitAbilityLevel(u,'Ainv') >= 1 then
            call BJDebugMsg("The native SetUnitInvulnerable does just add the 'Ainv' ability") // Didn't appear. =P
        endif
    endfunction
    
endlibrary

library InvulnerabilityTest initializer init

    private function init takes nothing returns nothing
        local unit u = CreateUnit(Player(0),'hfoo',0,0,270)
        call SetUnitInvulnerable(u,true)
        if GetUnitAbilityLevel(u,'Avul') >= 1 then
            call BJDebugMsg("The native SetUnitInvulnerable does just add the 'Avul' ability") // IT APPEARS!
        endif
    endfunction

endlibrary