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-- SafeGetUnit
-----------------------------------------------------------------------------------------------------------------------------
-- Description:
--     Safely get the unit, meaning it wil return the unit, or nil, depending upon unit existance without throwing an error.
--     This function wraps ScenEdit_GetUnit in a pcall and traps the error, if one is thrown by Command.
--     Use this where you normally have ScenEdit_GetUnit (with the same parameters)
--     If all three parameters give, guid will be used.
--     
-- Parameters:
--		UnitSelector        table	 must have either guid, or name and side defined to work.
--		UnitSelector.guid   string   string containing the target unit's unique guid (unique to this game instance)
--		UnitSelector.side   string   string containing the target unit's side
--		UnitSelector.name   string   string containing the target unit's name
--
-- Return: the unit wrapper loaded with the unit data, or nil on any error.
--
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SafeGetUnit =
function(unitSelector)
    if unitSelector == nil or type(unitSelector) ~= 'table' then
        return nil
    end
    local side_name = unitSelector.side
    local unit_name = unitSelector.name
    local unit_guid = unitSelector.guid
    local retVal = nil
    local e , p
    if (unitguid ~= nil and type(guid == 'string')) then
        --potentially good guid
        e, p = pcall(ScenEdit_GetUnit,{side='test', name='test_unit'})
        if e==true and p~= nil then
            retVal = p
        end
    elseif (side_name ~= nil and type(side_name == 'string')) and
           (unit_name ~= nil and type(unit_name == 'string')) then
        --potenitally good side and unit values
        e, p = pcall(ScenEdit_GetUnit,{side='test', name='test_unit'})
        if e==true and p~= nil then
            retVal = p
        end
    end
    return retVal
end





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-- SafeGetUnit Test Code
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local function RunSafeGetUnitTest(mySide, myUnit, testSide, testUnit, successExpected)
    ScenEdit_AddSide({name=mySide})
    ScenEdit_AddUnit({side=mySide, type='Facility', name=myUnit, dbid=2784, latitude=19.004100276608, longitude=110.24596193077, }) 
    local u = SafeGetUnit({side=testSide, name=testUnit})
    
    if successExpected == true then
        if (u ~= nil) and (u.name == myUnit) and (u.side == mySide) then print 'PASSED'
        else print('FAILED')
        end
    else
        if (u == nil) then print 'PASSED'
        else print('FAILED')
        end
    end
    ScenEdit_RemoveSide({name=mySide})
end

--test 1 - good side, good unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    local testSide = 'test'
    local testUnit = 'test_unit'
    RunSafeGetUnitTest(mySide, myUnit, testSide, testUnit, true)
end
--test 2 - good side, bad unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    local testSide = 'test'
    local testUnit = 'asdf'
    RunSafeGetUnitTest(mySide, myUnit, testSide, testUnit, false)
end

--test 3 - bad side, good unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    local testSide = 'asdf'
    local testUnit = 'test_unit'
    RunSafeGetUnitTest(mySide, myUnit, testSide, testUnit, false)
end

--test 4 - bad side, bad unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    local testSide = 'asdf'
    local testUnit = 'asdf'
    RunSafeGetUnitTest(mySide, myUnit, testSide, testUnit, false)
end

--test 5 - good side, nil unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    local testSide = 'test'
    local testUnit = nil
    RunSafeGetUnitTest(mySide, myUnit, testSide, testUnit, false)
end

--test 6 - nil side, good unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    local testSide = nil
    local testUnit = 'test_unit'
    RunSafeGetUnitTest(mySide, myUnit, testSide, testUnit, false)
end

--test 7 - nil side, nil unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    local testSide = nil
    local testUnit = nil
    RunSafeGetUnitTest_1(mySide, myUnit, testSide, testUnit, false)
end

--test 8 - good guid (only)
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    ScenEdit_AddSide({name=mySide})
    ScenEdit_AddUnit({side=mySide, type='Facility', name=myUnit, dbid=2784, latitude=19.004100276608, longitude=110.24596193077, }) 
    tUnit = ScenEdit_GetUnit({side=mySide, name=myUnit})
    local testGuid = tUnit.guid
    local result = SafeGetUnit({guid=testGuid})
    if (result ~= nil) and (result.name == myUnit) and (result.side == mySide) then print 'PASSED'
    else print('FAILED')
    end
    ScenEdit_RemoveSide({name=mySide})
end

--test 9 - bad guid (only)
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    ScenEdit_AddSide({name=mySide})
    ScenEdit_AddUnit({side=mySide, type='Facility', name=myUnit, dbid=2784, latitude=19.004100276608, longitude=110.24596193077, }) 
    tUnit = ScenEdit_GetUnit({side=mySide, name=myUnit})
    local result = SafeGetUnit({guid='asdf'})
    if (result == nil) then print 'PASSED'
    else print('FAILED')
    end
    ScenEdit_RemoveSide({name=mySide})
end

--test 10 - good guid, good side, good unit
do
    local mySide = 'test'
    local myUnit = 'test_unit'
    ScenEdit_AddSide({name=mySide})
    ScenEdit_AddUnit({side=mySide, type='Facility', name=myUnit, dbid=2784, latitude=19.004100276608, longitude=110.24596193077, }) 
    tUnit = ScenEdit_GetUnit({side=mySide, name=myUnit})
    local testGuid = tUnit.guid
    local result = SafeGetUnit({side=mySide, name=myUnit, guid=testGuid})
    if (result ~= nil) and (result.name == myUnit) and (result.side == mySide) then print 'PASSED'
    else print('FAILED')
    end
    ScenEdit_RemoveSide({name=mySide})
end

--test 11 - good guid, good side, good unit, but wrong side and unit
do
    local mySide = 'test'
    local myUnit1 = 'test_unit1'
    local myUnit2 = 'test_unit2'
    ScenEdit_AddSide({name=mySide})
    ScenEdit_AddUnit({side=mySide, type='Facility', name=myUnit1, dbid=2784, latitude=19.004100276608, longitude=110.24596193077, }) 
    ScenEdit_AddUnit({side=mySide, type='Facility', name=myUnit2, dbid=2784, latitude=19.004100276608, longitude=110.24596193077, }) 
    tUnit = ScenEdit_GetUnit({side=mySide, name=myUnit1})
    local testGuid = tUnit.guid
    local result = SafeGetUnit({side=mySide, name=myUnit2, guid=testGuid})
    if (result ~= nil) and (result.name == myUnit1) and (result.side == mySide) then print 'PASSED'
    else print('FAILED')
    end
    ScenEdit_RemoveSide({name=mySide})
end