Method test_large_read

Lib/test/test_os.py:326–337

(self, size)

                         "needs INT_MAX < PY_SSIZE_T_MAX")
    @support.bigmemtest(size=INT_MAX + 10, memuse=1, dry_run=False)
    def test_large_read(self, size):
        self.addCleanup(os_helper.unlink, os_helper.TESTFN)
        create_file(os_helper.TESTFN, b'test')

        # Issue #21932: Make sure that os.read() does not raise an
        # OverflowError for size larger than INT_MAX
        with open(os_helper.TESTFN, "rb") as fp:
            data = os.read(fp.fileno(), size)

        # The test does not try to read more than 2 GiB at once because the
        # operating system is free to return less bytes than requested.
        self.assertEqual(data, b'test')


    @support.cpython_only