backport test_fileio

Lib/test/test_fileio.py

+# Adapted from test_file.py by Daniel Stutzbach
+#from __future__ import unicode_literals
+
+import sys
+import os
+import unittest
+from array import array
+from weakref import proxy
+
+from test.test_support import TESTFN, findfile, run_unittest
+from UserList import UserList
+
+import _fileio
+
+class AutoFileTests(unittest.TestCase):
+    # file tests for which a test file is automatically set up
+
+    def setUp(self):
+        self.f = _fileio._FileIO(TESTFN, 'w')
+
+    def tearDown(self):
+        if self.f:
+            self.f.close()
+        os.remove(TESTFN)
+
+    def testWeakRefs(self):
+        # verify weak references
+        p = proxy(self.f)
+        p.write(bytes(range(10)))
+        self.assertEquals(self.f.tell(), p.tell())
+        self.f.close()
+        self.f = None
+        self.assertRaises(ReferenceError, getattr, p, 'tell')
+
+    def testSeekTell(self):
+        self.f.write(bytes(bytearray(range(20))))
+        self.assertEquals(self.f.tell(), 20)
+        self.f.seek(0)
+        self.assertEquals(self.f.tell(), 0)
+        self.f.seek(10)
+        self.assertEquals(self.f.tell(), 10)
+        self.f.seek(5, 1)
+        self.assertEquals(self.f.tell(), 15)
+        self.f.seek(-5, 1)
+        self.assertEquals(self.f.tell(), 10)
+        self.f.seek(-5, 2)
+        self.assertEquals(self.f.tell(), 15)
+
+    def testAttributes(self):
+        # verify expected attributes exist
+        f = self.f
+
+        self.assertEquals(f.mode, "w")
+        self.assertEquals(f.closed, False)
+
+        # verify the attributes are readonly
+        for attr in 'mode', 'closed':
+            self.assertRaises((AttributeError, TypeError),
+                              setattr, f, attr, 'oops')
+
+    def testReadinto(self):
+        # verify readinto
+        self.f.write(bytes(bytearray([1, 2])))
+        self.f.close()
+        a = array('b', b'x'*10)
+        self.f = _fileio._FileIO(TESTFN, 'r')
+        n = self.f.readinto(a)
+        self.assertEquals(array('b', [1, 2]), a[:n])
+
+    def testRepr(self):
+        self.assertEquals(repr(self.f),
+                          "_fileio._FileIO(%d, %s)" % (self.f.fileno(),
+                                                       repr(self.f.mode)))
+
+    def testErrors(self):
+        f = self.f
+        self.assert_(not f.isatty())
+        self.assert_(not f.closed)
+        #self.assertEquals(f.name, TESTFN)
+        self.assertRaises(ValueError, f.read, 10) # Open for reading
+        f.close()
+        self.assert_(f.closed)
+        f = _fileio._FileIO(TESTFN, 'r')
+        self.assertRaises(TypeError, f.readinto, "")
+        self.assert_(not f.closed)
+        f.close()
+        self.assert_(f.closed)
+
+    def testMethods(self):
+        methods = ['fileno', 'isatty', 'read', 'readinto',
+                   'seek', 'tell', 'truncate', 'write', 'seekable',
+                   'readable', 'writable']
+        if sys.platform.startswith('atheos'):
+            methods.remove('truncate')
+
+        self.f.close()
+        self.assert_(self.f.closed)
+
+        for methodname in methods:
+            method = getattr(self.f, methodname)
+            # should raise on closed file
+            self.assertRaises(ValueError, method)
+
+
+class OtherFileTests(unittest.TestCase):
+
+    def testAbles(self):
+        try:
+            f = _fileio._FileIO(TESTFN, "w")
+            self.assertEquals(f.readable(), False)
+            self.assertEquals(f.writable(), True)
+            self.assertEquals(f.seekable(), True)
+            f.close()
+
+            f = _fileio._FileIO(TESTFN, "r")
+            self.assertEquals(f.readable(), True)
+            self.assertEquals(f.writable(), False)
+            self.assertEquals(f.seekable(), True)
+            f.close()
+
+            f = _fileio._FileIO(TESTFN, "a+")
+            self.assertEquals(f.readable(), True)
+            self.assertEquals(f.writable(), True)
+            self.assertEquals(f.seekable(), True)
+            self.assertEquals(f.isatty(), False)
+            f.close()
+
+            if sys.platform != "win32":
+                try:
+                    f = _fileio._FileIO("/dev/tty", "a")
+                except EnvironmentError:
+                    # When run in a cron job there just aren't any
+                    # ttys, so skip the test.  This also handles other
+                    # OS'es that don't support /dev/tty.
+                    pass
+                else:
+                    f = _fileio._FileIO("/dev/tty", "a")
+                    self.assertEquals(f.readable(), False)
+                    self.assertEquals(f.writable(), True)
+                    if sys.platform != "darwin" and \
+                       not sys.platform.startswith('freebsd') and \
+                       not sys.platform.startswith('sunos'):
+                        # Somehow /dev/tty appears seekable on some BSDs
+                        self.assertEquals(f.seekable(), False)
+                    self.assertEquals(f.isatty(), True)
+                    f.close()
+        finally:
+            os.unlink(TESTFN)
+
+    def testModeStrings(self):
+        # check invalid mode strings
+        for mode in ("", "aU", "wU+", "rb", "rt"):
+            try:
+                f = _fileio._FileIO(TESTFN, mode)
+            except ValueError:
+                pass
+            else:
+                f.close()
+                self.fail('%r is an invalid file mode' % mode)
+
+    def testUnicodeOpen(self):
+        # verify repr works for unicode too
+        f = _fileio._FileIO(str(TESTFN), "w")
+        f.close()
+        os.unlink(TESTFN)
+
+    def testBadModeArgument(self):
+        # verify that we get a sensible error message for bad mode argument
+        bad_mode = "qwerty"
+        try:
+            f = _fileio._FileIO(TESTFN, bad_mode)
+        except ValueError as msg:
+            if msg.args[0] != 0:
+                s = str(msg)
+                if s.find(TESTFN) != -1 or s.find(bad_mode) == -1:
+                    self.fail("bad error message for invalid mode: %s" % s)
+            # if msg.args[0] == 0, we're probably on Windows where there may be
+            # no obvious way to discover why open() failed.
+        else:
+            f.close()
+            self.fail("no error for invalid mode: %s" % bad_mode)
+
+    def testTruncateOnWindows(self):
+        def bug801631():
+            # SF bug <http://www.python.org/sf/801631>
+            # "file.truncate fault on windows"
+            f = _fileio._FileIO(TESTFN, 'w')
+            f.write(bytes(bytearray(range(11))))
+            f.close()
+
+            f = _fileio._FileIO(TESTFN,'r+')
+            data = f.read(5)
+            if data != bytes(bytearray(range(5))):
+                self.fail("Read on file opened for update failed %r" % data)
+            if f.tell() != 5:
+                self.fail("File pos after read wrong %d" % f.tell())
+
+            f.truncate()
+            if f.tell() != 5:
+                self.fail("File pos after ftruncate wrong %d" % f.tell())
+
+            f.close()
+            size = os.path.getsize(TESTFN)
+            if size != 5:
+                self.fail("File size after ftruncate wrong %d" % size)
+
+        try:
+            bug801631()
+        finally:
+            os.unlink(TESTFN)
+
+    def testAppend(self):
+        try:
+            f = open(TESTFN, 'wb')
+            f.write(b'spam')
+            f.close()
+            f = open(TESTFN, 'ab')
+            f.write(b'eggs')
+            f.close()
+            f = open(TESTFN, 'rb')
+            d = f.read()
+            f.close()
+            self.assertEqual(d, b'spameggs')
+        finally:
+            try:
+                os.unlink(TESTFN)
+            except:
+                pass
+
+def test_main():
+    # Historically, these tests have been sloppy about removing TESTFN.
+    # So get rid of it no matter what.
+    try:
+        run_unittest(AutoFileTests, OtherFileTests)
+    finally:
+        if os.path.exists(TESTFN):
+            os.unlink(TESTFN)
+
+if __name__ == '__main__':
+    test_main()