Move package into src

Prevents accidental imports when running tests.
diff --git a/tests/test_rand.py b/tests/test_rand.py
new file mode 100644
index 0000000..8064011
--- /dev/null
+++ b/tests/test_rand.py
@@ -0,0 +1,212 @@
+# Copyright (c) Frederick Dean
+# See LICENSE for details.
+
+"""
+Unit tests for :py:obj:`OpenSSL.rand`.
+"""
+
+from unittest import main
+import os
+import stat
+import sys
+
+from OpenSSL import rand
+
+from .util import NON_ASCII, TestCase, b
+
+
+class RandTests(TestCase):
+    def test_bytes_wrong_args(self):
+        """
+        :py:obj:`OpenSSL.rand.bytes` raises :py:obj:`TypeError` if called with
+        the wrong number of arguments or with a non-:py:obj:`int` argument.
+        """
+        self.assertRaises(TypeError, rand.bytes)
+        self.assertRaises(TypeError, rand.bytes, None)
+        self.assertRaises(TypeError, rand.bytes, 3, None)
+
+    def test_insufficientMemory(self):
+        """
+        :py:obj:`OpenSSL.rand.bytes` raises :py:obj:`MemoryError` if more bytes
+        are requested than will fit in memory.
+        """
+        self.assertRaises(MemoryError, rand.bytes, sys.maxsize)
+
+    def test_bytes(self):
+        """
+        Verify that we can obtain bytes from rand_bytes() and
+        that they are different each time.  Test the parameter
+        of rand_bytes() for bad values.
+        """
+        b1 = rand.bytes(50)
+        self.assertEqual(len(b1), 50)
+        b2 = rand.bytes(num_bytes=50)  # parameter by name
+        self.assertNotEqual(b1, b2)  # Hip, Hip, Horay! FIPS complaince
+        b3 = rand.bytes(num_bytes=0)
+        self.assertEqual(len(b3), 0)
+        exc = self.assertRaises(ValueError, rand.bytes, -1)
+        self.assertEqual(str(exc), "num_bytes must not be negative")
+
+    def test_add_wrong_args(self):
+        """
+        When called with the wrong number of arguments, or with arguments not
+        of type :py:obj:`str` and :py:obj:`int`, :py:obj:`OpenSSL.rand.add`
+        raises :py:obj:`TypeError`.
+        """
+        self.assertRaises(TypeError, rand.add)
+        self.assertRaises(TypeError, rand.add, b("foo"), None)
+        self.assertRaises(TypeError, rand.add, None, 3)
+        self.assertRaises(TypeError, rand.add, b("foo"), 3, None)
+
+    def test_add(self):
+        """
+        :py:obj:`OpenSSL.rand.add` adds entropy to the PRNG.
+        """
+        rand.add(b('hamburger'), 3)
+
+    def test_seed_wrong_args(self):
+        """
+        When called with the wrong number of arguments, or with
+        a non-:py:obj:`str` argument, :py:obj:`OpenSSL.rand.seed` raises
+        :py:obj:`TypeError`.
+        """
+        self.assertRaises(TypeError, rand.seed)
+        self.assertRaises(TypeError, rand.seed, None)
+        self.assertRaises(TypeError, rand.seed, b("foo"), None)
+
+    def test_seed(self):
+        """
+        :py:obj:`OpenSSL.rand.seed` adds entropy to the PRNG.
+        """
+        rand.seed(b('milk shake'))
+
+    def test_status_wrong_args(self):
+        """
+        :py:obj:`OpenSSL.rand.status` raises :py:obj:`TypeError` when called
+        with any arguments.
+        """
+        self.assertRaises(TypeError, rand.status, None)
+
+    def test_status(self):
+        """
+        :py:obj:`OpenSSL.rand.status` returns :py:obj:`True` if the PRNG has
+        sufficient entropy, :py:obj:`False` otherwise.
+        """
+        # It's hard to know what it is actually going to return.  Different
+        # OpenSSL random engines decide differently whether they have enough
+        # entropy or not.
+        self.assertTrue(rand.status() in (1, 2))
+
+    def test_egd_wrong_args(self):
+        """
+        :py:obj:`OpenSSL.rand.egd` raises :py:obj:`TypeError` when called with
+        the wrong number of arguments or with arguments not of type
+        :py:obj:`str` and :py:obj:`int`.
+        """
+        self.assertRaises(TypeError, rand.egd)
+        self.assertRaises(TypeError, rand.egd, None)
+        self.assertRaises(TypeError, rand.egd, "foo", None)
+        self.assertRaises(TypeError, rand.egd, None, 3)
+        self.assertRaises(TypeError, rand.egd, "foo", 3, None)
+
+    def test_egd_missing(self):
+        """
+        :py:obj:`OpenSSL.rand.egd` returns :py:obj:`0` or :py:obj:`-1` if the
+        EGD socket passed to it does not exist.
+        """
+        result = rand.egd(self.mktemp())
+        expected = (-1, 0)
+        self.assertTrue(
+            result in expected,
+            "%r not in %r" % (result, expected))
+
+    def test_egd_missing_and_bytes(self):
+        """
+        :py:obj:`OpenSSL.rand.egd` returns :py:obj:`0` or :py:obj:`-1` if the
+        EGD socket passed to it does not exist even if a size argument is
+        explicitly passed.
+        """
+        result = rand.egd(self.mktemp(), 1024)
+        expected = (-1, 0)
+        self.assertTrue(
+            result in expected,
+            "%r not in %r" % (result, expected))
+
+    def test_cleanup_wrong_args(self):
+        """
+        :py:obj:`OpenSSL.rand.cleanup` raises :py:obj:`TypeError` when called
+        with any arguments.
+        """
+        self.assertRaises(TypeError, rand.cleanup, None)
+
+    def test_cleanup(self):
+        """
+        :py:obj:`OpenSSL.rand.cleanup` releases the memory used by the PRNG and
+        returns :py:obj:`None`.
+        """
+        self.assertIdentical(rand.cleanup(), None)
+
+    def test_load_file_wrong_args(self):
+        """
+        :py:obj:`OpenSSL.rand.load_file` raises :py:obj:`TypeError` when called
+        the wrong number of arguments or arguments not of type :py:obj:`str`
+        and :py:obj:`int`.
+        """
+        self.assertRaises(TypeError, rand.load_file)
+        self.assertRaises(TypeError, rand.load_file, "foo", None)
+        self.assertRaises(TypeError, rand.load_file, None, 1)
+        self.assertRaises(TypeError, rand.load_file, "foo", 1, None)
+
+    def test_write_file_wrong_args(self):
+        """
+        :py:obj:`OpenSSL.rand.write_file` raises :py:obj:`TypeError` when
+        called with the wrong number of arguments or a non-:py:obj:`str`
+        argument.
+        """
+        self.assertRaises(TypeError, rand.write_file)
+        self.assertRaises(TypeError, rand.write_file, None)
+        self.assertRaises(TypeError, rand.write_file, "foo", None)
+
+    def _read_write_test(self, path):
+        """
+        Verify that ``rand.write_file`` and ``rand.load_file`` can be used.
+        """
+        # Create the file so cleanup is more straightforward
+        with open(path, "w"):
+            pass
+
+        try:
+            # Write random bytes to a file
+            rand.write_file(path)
+
+            # Verify length of written file
+            size = os.stat(path)[stat.ST_SIZE]
+            self.assertEqual(1024, size)
+
+            # Read random bytes from file
+            rand.load_file(path)
+            rand.load_file(path, 4)  # specify a length
+        finally:
+            # Cleanup
+            os.unlink(path)
+
+    def test_bytes_paths(self):
+        """
+        Random data can be saved and loaded to files with paths specified as
+        bytes.
+        """
+        path = self.mktemp()
+        path += NON_ASCII.encode(sys.getfilesystemencoding())
+        self._read_write_test(path)
+
+    def test_unicode_paths(self):
+        """
+        Random data can be saved and loaded to files with paths specified as
+        unicode.
+        """
+        path = self.mktemp().decode('utf-8') + NON_ASCII
+        self._read_write_test(path)
+
+
+if __name__ == '__main__':
+    main()