File: test_SffIO.py

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# Copyright 2012 by Jeff Hussmann.  All rights reserved.
# Revisions copyright 2013-2016 by Peter Cock.  All rights reserved.
# This code is part of the Biopython distribution and governed by its
# license.  Please see the LICENSE file that should have been included
# as part of this package.

"""Tests for SffIO module."""

import re
import unittest
from io import BytesIO

from Bio.SeqIO.SffIO import _sff_find_roche_index, _sff_read_roche_index
from Bio.SeqIO.SffIO import _sff_do_slow_index
from Bio.SeqIO.SffIO import SffIterator, SffWriter, ReadRocheXmlManifest
from Bio import SeqIO

# sffinfo E3MFGYR02_random_10_reads.sff | sed -n '/>\|Run Prefix\|Region\|XY/p'
test_data = """
>E3MFGYR02JWQ7T
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  3946_2103
>E3MFGYR02JA6IL
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  3700_3115
>E3MFGYR02JHD4H
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  3771_2095
>E3MFGYR02GFKUC
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  2520_2738
>E3MFGYR02FTGED
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  2268_2739
>E3MFGYR02FR9G7
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  2255_0361
>E3MFGYR02GAZMS
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  2468_1618
>E3MFGYR02HHZ8O
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  2958_1574
>E3MFGYR02GPGB1
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  2633_0607
>E3MFGYR02F7Z7G
  Run Prefix:   R_2008_01_09_16_16_00_
  Region #:     2
  XY Location:  2434_1658"""


class TestUAN(unittest.TestCase):
    """Test annotations."""

    def setUp(self):
        self.records = list(SeqIO.parse("Roche/E3MFGYR02_random_10_reads.sff", "sff"))
        self.test_annotations = {}
        for line in test_data.splitlines():
            fields = re.split(r"\s+", line.strip())
            if ">" in line:
                current_name = fields[0].lstrip(">")
                self.test_annotations[current_name] = {}
            elif "Prefix" in line:
                time_list = [int(v) for v in fields[2].split("_")[1:-1]]
                self.test_annotations[current_name]["time"] = time_list
            elif "Region" in line:
                region = int(fields[-1])
                self.test_annotations[current_name]["region"] = region
            elif "XY" in line:
                x, y = [int(v) for v in fields[-1].split("_")]
                self.test_annotations[current_name]["coords"] = (x, y)

    def test_time(self):
        for record in self.records:
            self.assertEqual(
                record.annotations["time"], self.test_annotations[record.name]["time"]
            )

    def test_region(self):
        for record in self.records:
            self.assertEqual(
                record.annotations["region"],
                self.test_annotations[record.name]["region"],
            )

    def test_coords(self):
        for record in self.records:
            self.assertEqual(
                record.annotations["coords"],
                self.test_annotations[record.name]["coords"],
            )


class TestErrors(unittest.TestCase):
    with open("Roche/E3MFGYR02_random_10_reads.sff", "rb") as handle:
        good = handle.read()

    def test_empty(self):
        fh = BytesIO()
        try:
            records = list(SeqIO.parse(fh, "sff"))
        except ValueError as err:
            self.assertEqual(str(err), "Empty file.")
        else:
            self.assertTrue(False, "Empty file did not raise exception")

    def check_bad_header(self, header, msg):
        try:
            records = list(SeqIO.parse(BytesIO(header), "sff"))
        except ValueError as err:
            if isinstance(msg, (tuple, list)):
                self.assertIn(str(err), msg, "Unexpected error: %s" % err)
            else:
                self.assertEqual(str(err), msg)
        else:
            self.assertTrue(False, "Test SFF header only did not raise exception")

    def test_30bytes(self):
        self.check_bad_header(b"x" * 30, "File too small to hold a valid SFF header.")

    def test_31bytes(self):
        self.check_bad_header(
            b"x" * 31,
            (
                "SFF file did not start '.sff', but 'xxxx'",
                "SFF file did not start '.sff', but b'xxxx'",
            ),
        )

    def test_31bytes_index_header(self):
        self.check_bad_header(
            b".srt" + b"x" * 27, "Handle seems to be at SFF index block, not start"
        )

    def test_31bytes_bad_ver(self):
        self.check_bad_header(
            b".sff1.00" + b"x" * 23, "Unsupported SFF version in header, 49.46.48.48"
        )

    def test_31bytes_bad_flowgram(self):
        self.check_bad_header(
            b".sff\x00\x00\x00\x01" + b"x" * 23,
            "Flowgram format code 120 not supported",
        )

    def test_bad_index_offset(self):
        bad = self.good[:12] + b"\x00\x00\x00\x00" + self.good[16:]
        self.check_bad_header(bad, "Index offset 0 but index length 764")

    def test_bad_index_length(self):
        bad = self.good[:16] + b"\x00\x00\x00\x00" + self.good[20:]
        self.check_bad_header(bad, "Index offset 16824 but index length 0")

    def test_bad_index_eof(self):
        # Semi-random edit to the index offset value,
        bad = self.good[:13] + b"\x01" + self.good[14:]
        self.check_bad_header(
            bad,
            "Gap of 65536 bytes after final record end 16824, "
            "before 82360 where index starts?",
        )

    def test_no_index(self):
        # Does a lot of work to create a no-index SFF file
        # (in the process checking this bit of SffWriter works)
        records = list(SeqIO.parse(BytesIO(self.good), "sff"))
        with BytesIO() as handle:
            writer = SffWriter(handle, index=False)
            count = writer.write_file(records)
            self.assertEqual(count, len(records))
            handle.seek(0)
            new = list(SeqIO.parse(handle, "sff"))
            self.assertEqual(len(records), len(new))
            for a, b in zip(records, new):
                self.assertEqual(a.id, b.id)
            handle.seek(0)
            try:
                values = _sff_find_roche_index(handle)
            except ValueError as err:
                self.assertEqual(str(err), "No index present in this SFF file")
            else:
                self.assertTrue(
                    False, "Test _sff_find_roche_index did not raise exception"
                )

    def test_unknown_index(self):
        # TODO - Add SFF file with no index,
        # self.assertEqual(str(err), "No index present in this SFF file")
        with open("Roche/E3MFGYR02_alt_index_in_middle.sff", "rb") as handle:
            try:
                values = _sff_find_roche_index(handle)
            except ValueError as err:
                self.assertIn(
                    str(err),
                    (
                        "Unknown magic number '.diy' in SFF index header:\n'.diy1.00'",
                        "Unknown magic number b'.diy' in SFF index header:\nb'.diy1.00'",
                    ),
                )
            else:
                self.assertTrue(
                    False, "Test _sff_find_roche_index did not raise exception"
                )

    def check_sff_read_roche_index(self, data, msg):
        handle = BytesIO(data)
        try:
            index = list(_sff_read_roche_index(handle))
        except ValueError as err:
            self.assertEqual(str(err), msg)
        else:
            self.assertTrue(False, "_sff_read_roche_index did not raise exception")

    def test_premature_end_of_index(self):
        self.check_sff_read_roche_index(self.good[:-50], "Premature end of file!")

    def test_index_name_no_null(self):
        self.assertEqual(self.good[17502:17503], b"\x00")
        self.check_sff_read_roche_index(
            self.good[:17502] + b"x" + self.good[17503:],
            "Expected a null terminator to the read name.",
        )

    def test_index_mft_version(self):
        self.assertEqual(self.good[16824:16832], b".mft1.00")
        self.check_sff_read_roche_index(
            self.good[:16828] + b"\x01\x02\x03\x04" + self.good[16832:],
            "Unsupported version in .mft index header, 1.2.3.4",
        )

    def test_index_mft_data_size(self):
        self.assertEqual(self.good[16824:16832], b".mft1.00")
        self.check_sff_read_roche_index(
            self.good[:16836] + b"\x00\x00\x00\x00" + self.good[16840:],
            "Problem understanding .mft index header, 764 != 8 + 8 + 548 + 0",
        )

    def test_index_lengths(self):
        # Reduce the number of reads from 10 to 9 so index loading fails...
        self.assertEqual(self.good[20:24], b"\x00\x00\x00\x0A")
        self.check_sff_read_roche_index(
            self.good[:20] + b"\x00\x00\x00\x09" + self.good[24:],
            "Problem with index length? 17568 vs 17588",
        )

    def test_no_manifest_xml(self):
        with open("Roche/E3MFGYR02_no_manifest.sff", "rb") as handle:
            try:
                xml = ReadRocheXmlManifest(handle)
            except ValueError as err:
                self.assertEqual(str(err), "No XML manifest found")
            else:
                self.assertTrue(False, "ReadRocheXmlManifest did not raise exception")


class TestIndex(unittest.TestCase):
    """Test SFF index."""

    def test_manifest(self):
        filename = "Roche/E3MFGYR02_random_10_reads.sff"
        with open(filename, "rb") as handle:
            metadata = ReadRocheXmlManifest(handle)

    def test_both_ways(self):
        filename = "Roche/E3MFGYR02_random_10_reads.sff"
        with open(filename, "rb") as handle:
            index1 = sorted(_sff_read_roche_index(handle))
        with open(filename, "rb") as handle:
            index2 = sorted(_sff_do_slow_index(handle))
        self.assertEqual(index1, index2)
        with open(filename, "rb") as handle:
            self.assertEqual(len(index1), len(list(SffIterator(handle))))
        with open(filename, "rb") as handle:
            self.assertEqual(
                len(index1), len(list(SffIterator(BytesIO(handle.read()))))
            )


class TestAlternativeIndexes(unittest.TestCase):
    filename = "Roche/E3MFGYR02_random_10_reads.sff"
    with open(filename, "rb") as handle:
        sff = list(SffIterator(handle))

    def check_same(self, new_sff):
        self.assertEqual(len(self.sff), len(new_sff))
        for old, new in zip(self.sff, new_sff):
            self.assertEqual(old.id, new.id)
            self.assertEqual(str(old.seq), str(new.seq))

    def test_alt_index_at_end(self):
        with open("Roche/E3MFGYR02_alt_index_at_end.sff", "rb") as handle:
            sff2 = list(SffIterator(handle))
        self.check_same(sff2)

    def test_alt_index_at_start(self):
        with open("Roche/E3MFGYR02_alt_index_at_start.sff", "rb") as handle:
            sff2 = list(SffIterator(handle))
        self.check_same(sff2)

    def test_alt_index_in_middle(self):
        with open("Roche/E3MFGYR02_alt_index_in_middle.sff", "rb") as handle:
            sff2 = list(SffIterator(handle))
        self.check_same(sff2)

    def test_index_at_start(self):
        with open("Roche/E3MFGYR02_index_at_start.sff", "rb") as handle:
            sff2 = list(SffIterator(handle))
        self.check_same(sff2)

    def test_index_in_middle(self):
        with open("Roche/E3MFGYR02_index_in_middle.sff", "rb") as handle:
            sff2 = list(SffIterator(handle))
        self.check_same(sff2)

    def test_trim(self):
        with open(self.filename, "rb") as handle:
            sff_trim = list(SffIterator(handle, trim=True))
        self.assertEqual(len(self.sff), len(sff_trim))
        for old, new in zip(self.sff, sff_trim):
            self.assertEqual(old.id, new.id)


class TestConcatenated(unittest.TestCase):
    """Test concatenated SFF files."""

    def test_parses_gzipped_stream(self):
        import gzip

        count = 0
        with gzip.open("Roche/E3MFGYR02_random_10_reads.sff.gz", "rb") as fh:
            for record in SeqIO.parse(fh, "sff"):
                count += 1
        self.assertEqual(10, count)

    def test_parse1(self):
        count = 0
        caught = False
        try:
            for record in SeqIO.parse("Roche/invalid_greek_E3MFGYR02.sff", "sff"):
                count += 1
        except ValueError as err:
            self.assertTrue(
                "Additional data at end of SFF file, perhaps "
                "multiple SFF files concatenated? "
                "See offset 65296" in str(err),
                err,
            )
            caught = True
        self.assertTrue(caught, "Didn't spot concatenation")
        self.assertEqual(count, 24)

    def test_index1(self):
        try:
            d = SeqIO.index("Roche/invalid_greek_E3MFGYR02.sff", "sff")
        except ValueError as err:
            self.assertTrue(
                "Additional data at end of SFF file, perhaps "
                "multiple SFF files concatenated? "
                "See offset 65296" in str(err),
                err,
            )
        else:
            raise ValueError("Indxing Roche/invalid_greek_E3MFGYR02.sff should fail")

    def test_parse2(self):
        count = 0
        caught = False
        try:
            for record in SeqIO.parse("Roche/invalid_paired_E3MFGYR02.sff", "sff"):
                count += 1
        except ValueError as err:
            self.assertTrue(
                "Your SFF file is invalid, post index 5 byte "
                "null padding region ended '.sff' which could "
                "be the start of a concatenated SFF file? "
                "See offset 54371" in str(err),
                err,
            )
            caught = True
        self.assertTrue(caught, "Didn't spot concatenation")
        self.assertEqual(count, 20)

    def test_index2(self):
        try:
            d = SeqIO.index("Roche/invalid_paired_E3MFGYR02.sff", "sff")
        except ValueError as err:
            self.assertTrue(
                "Your SFF file is invalid, post index 5 byte "
                "null padding region ended '.sff' which could "
                "be the start of a concatenated SFF file? "
                "See offset 54371" in str(err),
                err,
            )
        else:
            raise ValueError("Indxing Roche/invalid_paired_E3MFGYR02.sff should fail")


class TestSelf(unittest.TestCase):
    """These tests were originally defined in SffIO.py as self-tests."""

    def test_read(self):
        filename = "Roche/E3MFGYR02_random_10_reads.sff"
        with open(filename, "rb") as handle:
            sff = list(SffIterator(handle))
        with open(filename, "rb") as handle:
            sff_trim = list(SffIterator(handle, trim=True))

        filename = "Roche/E3MFGYR02_random_10_reads_no_trim.fasta"
        fasta_no_trim = list(SeqIO.parse(filename, "fasta"))
        filename = "Roche/E3MFGYR02_random_10_reads_no_trim.qual"
        qual_no_trim = list(SeqIO.parse(filename, "qual"))

        filename = "Roche/E3MFGYR02_random_10_reads.fasta"
        fasta_trim = list(SeqIO.parse(filename, "fasta"))
        filename = "Roche/E3MFGYR02_random_10_reads.qual"
        qual_trim = list(SeqIO.parse(filename, "qual"))

        for s, sT, f, q, fT, qT in zip(
            sff, sff_trim, fasta_no_trim, qual_no_trim, fasta_trim, qual_trim
        ):
            self.assertEqual(len({s.id, f.id, q.id}), 1)  # All values are the same
            self.assertEqual(str(s.seq), str(f.seq))
            self.assertEqual(
                s.letter_annotations["phred_quality"],
                q.letter_annotations["phred_quality"],
            )
            self.assertEqual(
                len({s.id, sT.id, fT.id, qT.id}), 1
            )  # All values are the same
            self.assertEqual(str(sT.seq), str(fT.seq))
            self.assertEqual(
                sT.letter_annotations["phred_quality"],
                qT.letter_annotations["phred_quality"],
            )

    def test_write(self):
        filename = "Roche/E3MFGYR02_random_10_reads.sff"
        with open(filename, "rb") as handle:
            metadata = ReadRocheXmlManifest(handle)
        with open(filename, "rb") as handle:
            sff = list(SffIterator(handle))
        b_handle = BytesIO()
        w = SffWriter(b_handle, xml=metadata)
        w.write_file(sff)  # list
        data = b_handle.getvalue()
        # And again with an iterator...
        handle = BytesIO()
        w = SffWriter(handle, xml=metadata)
        w.write_file(iter(sff))
        self.assertEqual(data, handle.getvalue())
        # Check 100% identical to the original:
        with open(filename, "rb") as handle:
            original = handle.read()
        self.assertEqual(len(data), len(original))
        self.assertEqual(data, original)
        del data

    def test_index(self):
        filename = "Roche/greek.sff"
        with open(filename, "rb") as a_handle, open(filename, "rb") as b_handle:
            index1 = sorted(_sff_read_roche_index(a_handle))
            index2 = sorted(_sff_do_slow_index(b_handle))
            self.assertEqual(index1, index2)

    def test_read_wrong(self):
        filename = "Roche/greek.sff"
        with open(filename, "rb") as handle:
            self.assertRaises(ValueError, ReadRocheXmlManifest, handle)

        with open(filename, "rb") as handle:
            for record in SffIterator(handle):
                pass

            def fileiter(handle):
                for record in SffIterator(handle):
                    # print(record.id)
                    i = record.id

            self.assertRaises(ValueError, fileiter, handle)


if __name__ == "__main__":
    runner = unittest.TextTestRunner(verbosity=2)
    unittest.main(testRunner=runner)

if False:
    # Ugly code to make test files...
    index = ".diy1.00This is a fake index block (DIY = Do It Yourself), which is allowed under the SFF standard.\0"
    padding = len(index) % 8
    if padding:
        padding = 8 - padding
    index += chr(0) * padding
    assert len(index) % 8 == 0

    # Ugly bit of code to make a fake index at start
    index = ".diy1.00This is a fake index block (DIY = Do It Yourself), which is allowed under the SFF standard.\0"
    padding = len(index) % 8
    if padding:
        padding = 8 - padding
    index += chr(0) * padding
    with open("Roche/E3MFGYR02_random_10_reads.sff", "rb") as handle:
        records = list(SffIterator(handle))
    with open("Roche/E3MFGYR02_alt_index_at_start.sff", "w") as out_handle:
        w = SffWriter(out_handle, index=False, xml=None)
        # Fake the header...
        w._number_of_reads = len(records)
        w._index_start = 0
        w._index_length = 0
        w._key_sequence = records[0].annotations["flow_key"]
        w._flow_chars = records[0].annotations["flow_chars"]
        w._number_of_flows_per_read = len(w._flow_chars)
        w.write_header()
        w._index_start = out_handle.tell()
        w._index_length = len(index)
        out_handle.seek(0)
        w.write_header()  # this time with index info
        w.handle.write(index)
        for record in records:
            w.write_record(record)
    with open("Roche/E3MFGYR02_alt_index_at_start.sff", "rb") as handle:
        records2 = list(SffIterator(handle))
    for old, new in zip(records, records2):
        assert str(old.seq) == str(new.seq)
    with open("Roche/E3MFGYR02_alt_index_at_start.sff", "rb") as handle:
        i = list(_sff_do_slow_index(handle))

    # Ugly bit of code to make a fake index in middle
    index = ".diy1.00This is a fake index block (DIY = Do It Yourself), which is allowed under the SFF standard.\0"
    padding = len(index) % 8
    if padding:
        padding = 8 - padding
    index += chr(0) * padding
    with open("Roche/E3MFGYR02_random_10_reads.sff", "rb") as handle:
        records = list(SffIterator(handle))
    with open("Roche/E3MFGYR02_alt_index_in_middle.sff", "w") as out_handle:
        w = SffWriter(out_handle, index=False, xml=None)
        # Fake the header...
        w._number_of_reads = len(records)
        w._index_start = 0
        w._index_length = 0
        w._key_sequence = records[0].annotations["flow_key"]
        w._flow_chars = records[0].annotations["flow_chars"]
        w._number_of_flows_per_read = len(w._flow_chars)
        w.write_header()
        for record in records[:5]:
            w.write_record(record)
        w._index_start = out_handle.tell()
        w._index_length = len(index)
        w.handle.write(index)
        for record in records[5:]:
            w.write_record(record)
        out_handle.seek(0)
        w.write_header()  # this time with index info
    with open("Roche/E3MFGYR02_alt_index_in_middle.sff", "rb") as handle:
        records2 = list(SffIterator(handle))
    for old, new in zip(records, records2):
        assert str(old.seq) == str(new.seq)
    with open("Roche/E3MFGYR02_alt_index_in_middle.sff", "rb") as handle:
        j = list(_sff_do_slow_index(handle))

    # Ugly bit of code to make a fake index at end
    with open("Roche/E3MFGYR02_random_10_reads.sff", "rb") as handle:
        records = list(SffIterator(handle))
    with open("Roche/E3MFGYR02_alt_index_at_end.sff", "w") as out_handle:
        w = SffWriter(out_handle, index=False, xml=None)
        # Fake the header...
        w._number_of_reads = len(records)
        w._index_start = 0
        w._index_length = 0
        w._key_sequence = records[0].annotations["flow_key"]
        w._flow_chars = records[0].annotations["flow_chars"]
        w._number_of_flows_per_read = len(w._flow_chars)
        w.write_header()
        for record in records:
            w.write_record(record)
        w._index_start = out_handle.tell()
        w._index_length = len(index)
        out_handle.write(index)
        out_handle.seek(0)
        w.write_header()  # this time with index info
    with open("Roche/E3MFGYR02_alt_index_at_end.sff", "rb") as handle:
        records2 = list(SffIterator(handle))
    for old, new in zip(records, records2):
        assert str(old.seq) == str(new.seq)
    with unittest.TestCase.assertRaises(None, ValueError):
        with open("Roche/E3MFGYR02_alt_index_at_end.sff", "rb") as handle:
            print(ReadRocheXmlManifest(handle))
    with open("Roche/E3MFGYR02_alt_index_at_end.sff", "rb") as handle:
        k = list(_sff_do_slow_index(handle))
    print("Done")