#!/usr/bin/env pytest
###############################################################################
# $Id: mem.py b627cf4cda1170c4a1a29609b0531334bb0c55ea 2020-09-12 13:25:59 +0200 Even Rouault $
#
# Project:  GDAL/OGR Test Suite
# Purpose:  Test MEM format driver.
# Author:   Frank Warmerdam <warmerdam@pobox.com>
#
###############################################################################
# Copyright (c) 2005, Frank Warmerdam <warmerdam@pobox.com>
# Copyright (c) 2008-2012, Even Rouault <even dot rouault at spatialys.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
# DEALINGS IN THE SOFTWARE.
###############################################################################

import struct
from osgeo import gdal


import gdaltest
import pytest

###############################################################################
# Create a MEM dataset, and set some data, then test it.


def test_mem_1():

    #######################################################
    # Setup dataset
    drv = gdal.GetDriverByName('MEM')
    gdaltest.mem_ds = drv.Create('mem_1.mem', 50, 3)
    ds = gdaltest.mem_ds

    assert ds.GetProjection() == '', 'projection wrong'

    assert ds.GetGeoTransform(can_return_null=True) is None, 'geotransform wrong'

    raw_data = b''.join(struct.pack('f', v) for v in range(150))
    ds.WriteRaster(0, 0, 50, 3, raw_data,
                   buf_type=gdal.GDT_Float32,
                   band_list=[1])

    wkt = gdaltest.user_srs_to_wkt('EPSG:26711')
    ds.SetProjection(wkt)

    gt = (440720, 5, 0, 3751320, 0, -5)
    ds.SetGeoTransform(gt)

    band = ds.GetRasterBand(1)
    band.SetNoDataValue(-1.0)

    # Set GCPs()
    wkt_gcp = gdaltest.user_srs_to_wkt('EPSG:4326')
    gcps = [gdal.GCP(0, 1, 2, 3, 4)]
    ds.SetGCPs([], "")
    ds.SetGCPs(gcps, wkt_gcp)
    ds.SetGCPs([], "")
    ds.SetGCPs(gcps, wkt_gcp)
    ds.SetGCPs(gcps, wkt_gcp)

    #######################################################
    # Verify dataset.

    assert band.GetNoDataValue() == -1.0, 'no data is wrong'

    assert ds.GetProjection() == wkt, 'projection wrong'

    assert ds.GetGeoTransform() == gt, 'geotransform wrong'

    assert band.Checksum() == 1531, 'checksum wrong'

    assert ds.GetGCPCount() == 1, 'GetGCPCount wrong'

    assert len(ds.GetGCPs()) == 1, 'GetGCPs wrong'

    assert ds.GetGCPProjection() == wkt_gcp, 'GetGCPProjection wrong'

    assert band.DeleteNoDataValue() == 0, 'wrong return code'
    assert band.GetNoDataValue() is None, 'got nodata value whereas none was expected'

    gdaltest.mem_ds = None

###############################################################################
# Open an in-memory array.


def test_mem_2():

    gdal.PushErrorHandler('CPLQuietErrorHandler')
    ds = gdal.Open('MEM:::')
    gdal.PopErrorHandler()
    assert ds is None, 'opening MEM dataset should have failed.'

    try:
        import ctypes
    except ImportError:
        pytest.skip()

    for libname in ['msvcrt', 'libc.so.6']:
        try:
            crt = ctypes.CDLL(libname)
        except OSError:
            crt = None
        if crt is not None:
            break

    if crt is None:
        pytest.skip()

    malloc = crt.malloc
    malloc.argtypes = [ctypes.c_size_t]
    malloc.restype = ctypes.c_void_p

    free = crt.free
    free.argtypes = [ctypes.c_void_p]
    free.restype = None

    # allocate band data array.
    width = 50
    height = 3
    p = malloc(width * height * 4)
    if p is None:
        pytest.skip()
    float_p = ctypes.cast(p, ctypes.POINTER(ctypes.c_float))

    # build ds name.
    dsnames = ['MEM:::DATAPOINTER=0x%X,PIXELS=%d,LINES=%d,BANDS=1,DATATYPE=Float32,PIXELOFFSET=4,LINEOFFSET=%d,BANDOFFSET=0' % (p, width, height, width * 4),
               'MEM:::DATAPOINTER=0x%X,PIXELS=%d,LINES=%d,DATATYPE=Float32' % (p, width, height)]

    for dsname in dsnames:

        for i in range(width * height):
            float_p[i] = 5.0

        dsro = gdal.Open(dsname)
        if dsro is None:
            free(p)
            pytest.fail('opening MEM dataset failed in read only mode.')

        chksum = dsro.GetRasterBand(1).Checksum()
        if chksum != 750:
            print(chksum)
            free(p)
            pytest.fail('checksum failed.')
        dsro = None

        dsup = gdal.Open(dsname, gdal.GA_Update)
        if dsup is None:
            free(p)
            pytest.fail('opening MEM dataset failed in update mode.')

        dsup.GetRasterBand(1).Fill(100.0)
        dsup.FlushCache()

        if float_p[0] != 100.0:
            print(float_p[0])
            free(p)
            pytest.fail('fill seems to have failed.')

        dsup = None

    free(p)

###############################################################################
# Test creating a MEM dataset with the "MEM:::" name


def test_mem_3():

    drv = gdal.GetDriverByName('MEM')
    ds = drv.Create('MEM:::', 1, 1, 1)
    assert ds is not None
    ds = None

###############################################################################
# Test creating a band interleaved multi-band MEM dataset


def test_mem_4():

    drv = gdal.GetDriverByName('MEM')

    ds = drv.Create('', 100, 100, 3)
    expected_cs = [0, 0, 0]
    for i in range(3):
        cs = ds.GetRasterBand(i + 1).Checksum()
        assert cs == expected_cs[i], \
            ('did not get expected checksum for band %d' % (i + 1))

    ds.GetRasterBand(1).Fill(255)
    expected_cs = [57182, 0, 0]
    for i in range(3):
        cs = ds.GetRasterBand(i + 1).Checksum()
        assert cs == expected_cs[i], \
            ('did not get expected checksum for band %d after fill' % (i + 1))

    ds = None

###############################################################################
# Test creating a pixel interleaved multi-band MEM dataset


def test_mem_5():

    drv = gdal.GetDriverByName('MEM')

    ds = drv.Create('', 100, 100, 3, options=['INTERLEAVE=PIXEL'])
    expected_cs = [0, 0, 0]
    for i in range(3):
        cs = ds.GetRasterBand(i + 1).Checksum()
        assert cs == expected_cs[i], \
            ('did not get expected checksum for band %d' % (i + 1))

    ds.GetRasterBand(1).Fill(255)
    expected_cs = [57182, 0, 0]
    for i in range(3):
        cs = ds.GetRasterBand(i + 1).Checksum()
        assert cs == expected_cs[i], \
            ('did not get expected checksum for band %d after fill' % (i + 1))

    assert ds.GetMetadataItem('INTERLEAVE', 'IMAGE_STRUCTURE') == 'PIXEL', \
        'did not get expected INTERLEAVE value'

    ds = None

###############################################################################
# Test out-of-memory situations


def test_mem_6():

    if gdal.GetConfigOption('SKIP_MEM_INTENSIVE_TEST') is not None:
        pytest.skip()

    drv = gdal.GetDriverByName('MEM')

    # Multiplication overflow
    with gdaltest.error_handler():
        ds = drv.Create('', 1, 1, 0x7FFFFFFF, gdal.GDT_Float64)
    assert ds is None
    ds = None

    # Multiplication overflow
    with gdaltest.error_handler():
        ds = drv.Create('', 0x7FFFFFFF, 0x7FFFFFFF, 16)
    assert ds is None
    ds = None

    # Multiplication overflow
    with gdaltest.error_handler():
        ds = drv.Create('', 0x7FFFFFFF, 0x7FFFFFFF, 1, gdal.GDT_Float64)
    assert ds is None
    ds = None

    # Out of memory error
    with gdaltest.error_handler():
        ds = drv.Create('', 0x7FFFFFFF, 0x7FFFFFFF, 1, options=['INTERLEAVE=PIXEL'])
    assert ds is None
    ds = None

    # Out of memory error
    with gdaltest.error_handler():
        ds = drv.Create('', 0x7FFFFFFF, 0x7FFFFFFF, 1)
    assert ds is None
    ds = None

    # 32 bit overflow on 32-bit builds, or possible out of memory error
    ds = drv.Create('', 0x7FFFFFFF, 1, 0)
    with gdaltest.error_handler():
        ds.AddBand(gdal.GDT_Float64)

    # Will raise out of memory error in all cases
    ds = drv.Create('', 0x7FFFFFFF, 0x7FFFFFFF, 0)
    with gdaltest.error_handler():
        ret = ds.AddBand(gdal.GDT_Float64)
    assert ret != 0

###############################################################################
# Test AddBand()


def test_mem_7():

    drv = gdal.GetDriverByName('MEM')
    ds = drv.Create('MEM:::', 1, 1, 1)
    ds.AddBand(gdal.GDT_Byte, [])
    assert ds.RasterCount == 2
    ds = None

###############################################################################
# Test SetDefaultHistogram() / GetDefaultHistogram()


def test_mem_8():

    drv = gdal.GetDriverByName('MEM')
    ds = drv.Create('MEM:::', 1, 1, 1)
    ds.GetRasterBand(1).SetDefaultHistogram(0, 255, [])
    ds.GetRasterBand(1).SetDefaultHistogram(1, 2, [5, 6])
    ds.GetRasterBand(1).SetDefaultHistogram(1, 2, [3000000000, 4])
    hist = ds.GetRasterBand(1).GetDefaultHistogram(force=0)
    ds = None

    assert hist == (1.0, 2.0, 2, [3000000000, 4])

###############################################################################
# Test RasterIO()


def test_mem_9():

    # Test IRasterIO(GF_Read,)
    src_ds = gdal.Open('data/rgbsmall.tif')
    drv = gdal.GetDriverByName('MEM')

    for interleave in ['BAND', 'PIXEL']:
        out_ds = drv.CreateCopy('', src_ds, options=['INTERLEAVE=%s' % interleave])
        ref_data = src_ds.GetRasterBand(2).ReadRaster(20, 8, 4, 5)
        got_data = out_ds.GetRasterBand(2).ReadRaster(20, 8, 4, 5)
        if ref_data != got_data:
            import struct
            print(struct.unpack('B' * 4 * 5, ref_data))
            print(struct.unpack('B' * 4 * 5, got_data))
            pytest.fail(interleave)

        ref_data = src_ds.GetRasterBand(2).ReadRaster(20, 8, 4, 5, buf_pixel_space=3, buf_line_space=100)
        got_data = out_ds.GetRasterBand(2).ReadRaster(20, 8, 4, 5, buf_pixel_space=3, buf_line_space=100)
        assert ref_data == got_data, interleave

        ref_data = src_ds.ReadRaster(20, 8, 4, 5)
        got_data = out_ds.ReadRaster(20, 8, 4, 5)
        assert ref_data == got_data, interleave

        ref_data = src_ds.ReadRaster(20, 8, 4, 5, buf_pixel_space=3, buf_band_space=1)
        got_data = out_ds.ReadRaster(20, 8, 4, 5, buf_pixel_space=3, buf_band_space=1)
        assert ref_data == got_data, interleave

        out_ds.WriteRaster(20, 8, 4, 5, got_data, buf_pixel_space=3, buf_band_space=1)
        got_data = out_ds.ReadRaster(20, 8, 4, 5, buf_pixel_space=3, buf_band_space=1)
        assert ref_data == got_data, interleave

        ref_data = src_ds.ReadRaster(20, 8, 4, 5, buf_pixel_space=3, buf_line_space=100, buf_band_space=1)
        got_data = out_ds.ReadRaster(20, 8, 4, 5, buf_pixel_space=3, buf_line_space=100, buf_band_space=1)
        assert ref_data == got_data, interleave

        ref_data = src_ds.ReadRaster(20, 20, 4, 5, buf_type=gdal.GDT_Int32, buf_pixel_space=12, buf_band_space=4)
        got_data = out_ds.ReadRaster(20, 20, 4, 5, buf_type=gdal.GDT_Int32, buf_pixel_space=12, buf_band_space=4)
        assert ref_data == got_data, interleave
        out_ds.WriteRaster(20, 20, 4, 5, got_data, buf_type=gdal.GDT_Int32, buf_pixel_space=12, buf_band_space=4)
        got_data = out_ds.ReadRaster(20, 20, 4, 5, buf_type=gdal.GDT_Int32, buf_pixel_space=12, buf_band_space=4)
        assert ref_data == got_data, interleave

        # Test IReadBlock
        ref_data = src_ds.GetRasterBand(1).ReadRaster(0, 10, src_ds.RasterXSize, 1)
        # This is a bit nasty to have to do that. We should fix the core
        # to make that unnecessary
        out_ds.FlushCache()
        got_data = out_ds.GetRasterBand(1).ReadBlock(0, 10)
        assert ref_data == got_data, interleave

        # Test IRasterIO(GF_Write,)
        ref_data = src_ds.GetRasterBand(1).ReadRaster(2, 3, 4, 5)
        out_ds.GetRasterBand(1).WriteRaster(6, 7, 4, 5, ref_data)
        got_data = out_ds.GetRasterBand(1).ReadRaster(6, 7, 4, 5)
        assert ref_data == got_data

        # Test IRasterIO(GF_Write, change data type) + IWriteBlock() + IRasterIO(GF_Read, change data type)
        ref_data = src_ds.GetRasterBand(1).ReadRaster(10, 11, 4, 5, buf_type=gdal.GDT_Int32)
        out_ds.GetRasterBand(1).WriteRaster(10, 11, 4, 5, ref_data, buf_type=gdal.GDT_Int32)
        got_data = out_ds.GetRasterBand(1).ReadRaster(10, 11, 4, 5, buf_type=gdal.GDT_Int32)
        assert ref_data == got_data, interleave

        ref_data = src_ds.GetRasterBand(1).ReadRaster(10, 11, 4, 5)
        got_data = out_ds.GetRasterBand(1).ReadRaster(10, 11, 4, 5)
        assert ref_data == got_data, interleave

        # Test IRasterIO(GF_Write, resampling) + IWriteBlock() + IRasterIO(GF_Read, resampling)
        ref_data = src_ds.GetRasterBand(1).ReadRaster(10, 11, 4, 5)
        ref_data_zoomed = src_ds.GetRasterBand(1).ReadRaster(10, 11, 4, 5, 8, 10)
        out_ds.GetRasterBand(1).WriteRaster(10, 11, 8, 10, ref_data, 4, 5)
        got_data = out_ds.GetRasterBand(1).ReadRaster(10, 11, 8, 10)
        assert ref_data_zoomed == got_data, interleave

        got_data = out_ds.GetRasterBand(1).ReadRaster(10, 11, 8, 10, 4, 5)
        assert ref_data == got_data, interleave

    
###############################################################################
# Test BuildOverviews()


def test_mem_10():

    # Error case: building overview on a 0 band dataset
    ds = gdal.GetDriverByName('MEM').Create('', 1, 1, 0)
    with gdaltest.error_handler():
        ds.BuildOverviews('NEAR', [2])

    # Requesting overviews when they are not
    ds = gdal.GetDriverByName('MEM').Create('', 1, 1)
    assert ds.GetRasterBand(1).GetOverviewCount() == 0
    assert ds.GetRasterBand(1).GetOverview(-1) is None
    assert ds.GetRasterBand(1).GetOverview(0) is None

    # Single band case
    ds = gdal.GetDriverByName('MEM').CreateCopy('', gdal.Open('data/byte.tif'))
    for _ in range(2):
        ret = ds.BuildOverviews('NEAR', [2])
        assert ret == 0
        assert ds.GetRasterBand(1).GetOverviewCount() == 1
        cs = ds.GetRasterBand(1).GetOverview(0).Checksum()
        assert cs == 1087

    ret = ds.BuildOverviews('NEAR', [4])
    assert ret == 0
    assert ds.GetRasterBand(1).GetOverviewCount() == 2
    cs = ds.GetRasterBand(1).GetOverview(0).Checksum()
    assert cs == 1087
    cs = ds.GetRasterBand(1).GetOverview(1).Checksum()
    assert cs == 328

    ret = ds.BuildOverviews('NEAR', [2, 4])
    assert ret == 0
    assert ds.GetRasterBand(1).GetOverviewCount() == 2
    cs = ds.GetRasterBand(1).GetOverview(0).Checksum()
    assert cs == 1087
    cs = ds.GetRasterBand(1).GetOverview(1).Checksum()
    assert cs == 328

    # Test that average in one or several steps give the same result
    ds.GetRasterBand(1).GetOverview(0).Fill(0)
    ds.GetRasterBand(1).GetOverview(1).Fill(0)

    ret = ds.BuildOverviews('AVERAGE', [2, 4])
    assert ret == 0
    assert ds.GetRasterBand(1).GetOverviewCount() == 2
    cs = ds.GetRasterBand(1).GetOverview(0).Checksum()
    assert cs == 1152
    cs = ds.GetRasterBand(1).GetOverview(1).Checksum()
    assert cs == 240

    ds.GetRasterBand(1).GetOverview(0).Fill(0)
    ds.GetRasterBand(1).GetOverview(1).Fill(0)

    ret = ds.BuildOverviews('AVERAGE', [2])
    ret = ds.BuildOverviews('AVERAGE', [4])
    assert ret == 0
    assert ds.GetRasterBand(1).GetOverviewCount() == 2
    cs = ds.GetRasterBand(1).GetOverview(0).Checksum()
    assert cs == 1152
    cs = ds.GetRasterBand(1).GetOverview(1).Checksum()
    assert cs == 240

    ds = None

    # Multiple band case
    ds = gdal.GetDriverByName('MEM').CreateCopy('', gdal.Open('data/rgbsmall.tif'))
    ret = ds.BuildOverviews('NEAR', [2])
    assert ret == 0
    cs = ds.GetRasterBand(1).GetOverview(0).Checksum()
    assert cs == 5057
    cs = ds.GetRasterBand(2).GetOverview(0).Checksum()
    assert cs == 5304
    cs = ds.GetRasterBand(3).GetOverview(0).Checksum()
    assert cs == 5304
    ds = None

    # Clean overviews
    ds = gdal.GetDriverByName('MEM').CreateCopy('', gdal.Open('data/byte.tif'))
    ret = ds.BuildOverviews('NEAR', [2])
    assert ret == 0
    ret = ds.BuildOverviews('NONE', [])
    assert ret == 0
    assert ds.GetRasterBand(1).GetOverviewCount() == 0
    ds = None

###############################################################################
# Test CreateMaskBand()


def test_mem_11():

    # Error case: building overview on a 0 band dataset
    ds = gdal.GetDriverByName('MEM').Create('', 1, 1, 0)
    assert ds.CreateMaskBand(gdal.GMF_PER_DATASET) != 0

    # Per dataset mask on single band dataset
    ds = gdal.GetDriverByName('MEM').Create('', 1, 1)
    assert ds.CreateMaskBand(gdal.GMF_PER_DATASET) == 0
    assert ds.GetRasterBand(1).GetMaskFlags() == gdal.GMF_PER_DATASET
    mask = ds.GetRasterBand(1).GetMaskBand()
    cs = mask.Checksum()
    assert cs == 0
    mask.Fill(255)
    cs = mask.Checksum()
    assert cs == 3

    # Check that the per dataset mask is shared by all bands
    ds = gdal.GetDriverByName('MEM').Create('', 1, 1, 2)
    assert ds.CreateMaskBand(gdal.GMF_PER_DATASET) == 0
    mask1 = ds.GetRasterBand(1).GetMaskBand()
    mask1.Fill(255)
    mask2 = ds.GetRasterBand(2).GetMaskBand()
    cs = mask2.Checksum()
    assert cs == 3

    # Same but call it on band 2
    ds = gdal.GetDriverByName('MEM').Create('', 1, 1, 2)
    assert ds.GetRasterBand(2).CreateMaskBand(gdal.GMF_PER_DATASET) == 0
    mask2 = ds.GetRasterBand(2).GetMaskBand()
    mask2.Fill(255)
    mask1 = ds.GetRasterBand(1).GetMaskBand()
    cs = mask1.Checksum()
    assert cs == 3

    # Per band masks
    ds = gdal.GetDriverByName('MEM').Create('', 1, 1, 2)
    assert ds.GetRasterBand(1).CreateMaskBand(0) == 0
    assert ds.GetRasterBand(2).CreateMaskBand(0) == 0
    mask1 = ds.GetRasterBand(1).GetMaskBand()
    mask2 = ds.GetRasterBand(2).GetMaskBand()
    mask2.Fill(255)
    cs1 = mask1.Checksum()
    cs2 = mask2.Checksum()
    assert cs1 == 0 and cs2 == 3

###############################################################################
# Test CreateMaskBand() and overviews.


def test_mem_12():

    # Test on per-band mask
    ds = gdal.GetDriverByName('MEM').Create('', 10, 10, 2)
    ds.GetRasterBand(1).CreateMaskBand(0)
    ds.GetRasterBand(1).GetMaskBand().Fill(127)
    ds.BuildOverviews('NEAR', [2])
    cs = ds.GetRasterBand(1).GetOverview(0).GetMaskBand().Checksum()
    assert cs == 267

    # Default mask
    cs = ds.GetRasterBand(2).GetOverview(0).GetMaskBand().Checksum()
    assert cs == 283

    # Test on per-dataset mask
    ds = gdal.GetDriverByName('MEM').Create('', 10, 10, 2)
    ds.CreateMaskBand(gdal.GMF_PER_DATASET)
    ds.GetRasterBand(1).GetMaskBand().Fill(127)
    ds.BuildOverviews('NEAR', [2])
    cs = ds.GetRasterBand(1).GetOverview(0).GetMaskBand().Checksum()
    assert cs == 267
    cs2 = ds.GetRasterBand(2).GetOverview(0).GetMaskBand().Checksum()
    assert cs2 == cs

###############################################################################
# Check RAT support


def test_mem_rat():

    ds = gdal.GetDriverByName('MEM').Create('', 1, 1)
    ds.GetRasterBand(1).SetDefaultRAT(gdal.RasterAttributeTable())
    assert ds.GetRasterBand(1).GetDefaultRAT() is not None
    ds.GetRasterBand(1).SetDefaultRAT(None)
    assert ds.GetRasterBand(1).GetDefaultRAT() is None

###############################################################################
# Check CategoryNames support


def test_mem_categorynames():

    ds = gdal.GetDriverByName('MEM').Create('', 1, 1)
    ds.GetRasterBand(1).SetCategoryNames(['foo'])
    assert ds.GetRasterBand(1).GetCategoryNames() == ['foo']
    ds.GetRasterBand(1).SetCategoryNames([])
    assert ds.GetRasterBand(1).GetCategoryNames() is None


###############################################################################
# Check ColorTable support

def test_mem_colortable():

    ds = gdal.GetDriverByName('MEM').Create('', 1, 1)
    ct = gdal.ColorTable()
    ct.SetColorEntry(0, (255, 255, 255, 255))
    ds.GetRasterBand(1).SetColorTable(ct)
    assert ds.GetRasterBand(1).GetColorTable().GetCount() == 1
    ds.GetRasterBand(1).SetColorTable(None)
    assert ds.GetRasterBand(1).GetColorTable() is None


###############################################################################
# Test dataset RasterIO with non nearest resampling

def test_mem_dataset_rasterio_non_nearest_resampling_source_with_ovr():

    ds = gdal.GetDriverByName('MEM').Create('', 10, 10, 3)
    ds.GetRasterBand(1).Fill(255)
    ds.BuildOverviews('NONE', [2])
    ds.GetRasterBand(1).GetOverview(0).Fill(10)

    got_data = ds.ReadRaster(0,0,10,10,5,5)
    got_data = struct.unpack('B' * 5 * 5 * 3, got_data)
    assert got_data[0] == 10

    got_data = ds.ReadRaster(0,0,10,10,5,5,resample_alg=gdal.GRIORA_Cubic)
    got_data = struct.unpack('B' * 5 * 5 * 3, got_data)
    assert got_data[0] == 10

###############################################################################
# cleanup

def test_mem_cleanup():
    gdaltest.mem_ds = None



