Remove leftover support for Python 2

Also update cmstestsuite.sh() description, as it no longer matched the
implementation.

.github/CONTRIBUTING.md

@@ -17,7 +17,7 @@ For Python code, we generally follow [PEP 8](https://www.python.org/dev/peps/pep
 We get around Python flexible type system in several ways:
 * we try to avoid "magic" (e.g., generating or changing classes on the fly);
 * we are fairly verbose with naming, trying to help the reader with following the types;
-* we follow our type annotation system for method and function docstrings (planning to switch to [PEP 484](https://www.python.org/dev/peps/pep-0484/) when we will remove support for Python 2); see later for the format.
+* we follow our type annotation system for method and function docstrings (planning to switch to [PEP 484](https://www.python.org/dev/peps/pep-0484/)); see later for the format.
 
 We support Python 3 only, requiring at least version 3.6.
 

cms/db/filecacher.py

@@ -65,9 +65,6 @@ def copyfileobj(source_fobj, destination_fobj,
         while len(buffer) > 0:
             gevent.sleep(0)
             written = destination_fobj.write(buffer)
-            # FIXME remove this when we drop py2
-            if written is None:
-                break
             buffer = buffer[written:]
         gevent.sleep(0)
 

cms/grading/Sandbox.py

@@ -26,6 +26,7 @@
 import select
 import stat
 import tempfile
+import time
 from abc import ABCMeta, abstractmethod
 from functools import wraps, partial
 
@@ -34,7 +35,6 @@
 
 from cms import config, rmtree
 from cmscommon.commands import pretty_print_cmdline
-from cmscommon.datetime import monotonic_time
 
 
 logger = logging.getLogger(__name__)
@@ -594,7 +594,7 @@ def get_execution_wall_clock_time(self):
         if self.exec_time:
             return self.exec_time
         if self.popen_time:
-            self.exec_time = monotonic_time() - self.popen_time
+            self.exec_time = time.monotonic() - self.popen_time
             return self.exec_time
         return None
 
@@ -765,7 +765,7 @@ def preexec_fn(self):
             stderr_fd = subprocess.PIPE
 
         # Note down execution time
-        self.popen_time = monotonic_time()
+        self.popen_time = time.monotonic()
 
         # Actually call the Popen
         self.popen = self._popen(command,
@@ -995,8 +995,8 @@ def allow_writing_only(self, inner_paths):
                 os.path.realpath(os.path.join(self._home_dest, inner_path))
             # If an inner path is absolute (e.g., /fifo0/u0_to_m) then
             # it may be outside home and we should ignore it.
-            # FIXME: In Py3 use os.path.commonpath.
-            if not abs_inner_path.startswith(self._home_dest + "/"):
+            if os.path.commonpath([abs_inner_path,
+                                   self._home_dest]) != self._home_dest:
                 continue
             rel_inner_path = os.path.relpath(abs_inner_path, self._home_dest)
             outer_path = os.path.join(self._home, rel_inner_path)

cms/io/service.py

@@ -43,7 +43,6 @@
     get_service_address
 from cms.log import root_logger, shell_handler, ServiceFilter, \
     DetailedFormatter, LogServiceHandler, FileHandler
-from cmscommon.datetime import monotonic_time
 from .rpc import rpc_method, RemoteServiceServer, RemoteServiceClient, \
     FakeRemoteServiceClient
 
@@ -64,14 +63,14 @@ def repeater(func, period):
 
     """
     while True:
-        call = monotonic_time()
+        call = time.monotonic()
 
         try:
             func()
         except Exception:
             logger.error("Unexpected error.", exc_info=True)
 
-        gevent.sleep(max(call + period - monotonic_time(), 0))
+        gevent.sleep(max(call + period - time.monotonic(), 0))
 
 
 class Service:

cms/io/triggeredservice.py

@@ -29,7 +29,6 @@
 from gevent.event import Event
 
 from cms.io import PriorityQueue, Service, rpc_method
-from cmscommon.datetime import monotonic_time
 
 
 logger = logging.getLogger(__name__)
@@ -307,7 +306,7 @@ def _sweeper_loop(self):
 
         """
         while True:
-            self._sweeper_start = monotonic_time()
+            self._sweeper_start = time.monotonic()
             self._sweeper_event.clear()
 
             try:
@@ -318,7 +317,7 @@ def _sweeper_loop(self):
 
             self._sweeper_event.wait(max(self._sweeper_start +
                                          self._sweeper_timeout -
-                                         monotonic_time(), 0))
+                                         time.monotonic(), 0))
 
     def _sweep(self):
         """Check for missed operations."""

cms/locale/locale.py

@@ -223,9 +223,8 @@ def format_size(self, n):
             n /= self.PREFIX_FACTOR
             if n < self.PREFIX_FACTOR:
                 f = copy.copy(self.locale.decimal_formats[None])
-                # We need int because floor returns a float in py2.
                 # if 1000 <= n < 1024 d can be negative, cap to 0 decimals
-                d = max(0, int(2 - math.floor(math.log10(n))))
+                d = max(0, 2 - math.floor(math.log10(n)))
                 f.frac_prec = (d, d)
                 return (self.gettext(unit)
                         % babel.numbers.format_decimal(n, format=f,

cms/server/contest/handlers/contest.py

@@ -142,9 +142,7 @@ def get_current_user(self):
         cookie = self.get_secure_cookie(cookie_name)
 
         try:
-            # In py2 Tornado gives us the IP address as a native binary
-            # string, whereas ipaddress wants text (unicode) strings.
-            ip_address = ipaddress.ip_address(str(self.request.remote_ip))
+            ip_address = ipaddress.ip_address(self.request.remote_ip)
         except ValueError:
             logger.warning("Invalid IP address provided by Tornado: %s",
                            self.request.remote_ip)

cms/server/contest/handlers/main.py

@@ -173,9 +173,7 @@ def post(self):
         password = self.get_argument("password", "")
 
         try:
-            # In py2 Tornado gives us the IP address as a native binary
-            # string, whereas ipaddress wants text (unicode) strings.
-            ip_address = ipaddress.ip_address(str(self.request.remote_ip))
+            ip_address = ipaddress.ip_address(self.request.remote_ip)
         except ValueError:
             logger.warning("Invalid IP address provided by Tornado: %s",
                            self.request.remote_ip)

cms/server/contest/tokening.py

@@ -141,8 +141,7 @@ def generate_tokens(begin_timestamp, end_timestamp):
     if gen_number > 0 and (gen_max is None or avail < gen_max):
         num_periods_so_far = \
             (timestamp - start).total_seconds() // gen_interval.total_seconds()
-        # py2 needs the cast to int.
-        next_gen_time = start + gen_interval * (int(num_periods_so_far) + 1)
+        next_gen_time = start + gen_interval * (num_periods_so_far + 1)
 
     # If we have more tokens than how many we are allowed to play, cap
     # the result, and note that no more will be generated.

cms/server/jinja2_toolbox.py

@@ -88,9 +88,8 @@ def any_(ctx, l, test=None, *args):
     return False
 
 
-# FIXME once we drop py2 do dictselect(ctx, d, test=None, *args, by="key")
 @contextfilter
-def dictselect(ctx, d, test=None, *args, **kwargs):
+def dictselect(ctx, d, test=None, *args, by="key"):
     """Filter the given dict: keep only items that pass the given test.
 
     ctx (Context): a Jinja2 context, needed to retrieve the test
@@ -110,10 +109,6 @@ def dictselect(ctx, d, test=None, *args, **kwargs):
         test = bool
     else:
         test = ctx.environment.tests[test]
-    by = kwargs.pop("by", "key")
-    if len(kwargs) > 0:
-        raise ValueError("Invalid keyword argument: %s"
-                         % next(iter(kwargs.keys())))
     if by not in {"key", "value"}:
         raise ValueError("Invalid value of \"by\" keyword argument: %s" % by)
     return dict((k, v) for k, v in d.items()
@@ -168,10 +163,8 @@ def instrument_generic_toolbox(env):
     env.tests["today"] = today
 
 
-# TODO When dropping py2, let the arguments be `env, *, dataset` in
-# order to force the users to pass the dataset as a keyword argument.
 @environmentfunction
-def safe_get_task_type(env, dataset):
+def safe_get_task_type(env, *, dataset):
     try:
         return dataset.task_type_object
     # The task type's constructor is called, which may raise any
@@ -180,10 +173,8 @@ def safe_get_task_type(env, dataset):
         return env.undefined("TaskType not found: %s" % err)
 
 
-# TODO When dropping py2, let the arguments be `env, *, dataset` in
-# order to force the users to pass the dataset as a keyword argument.
 @environmentfunction
-def safe_get_score_type(env, dataset):
+def safe_get_score_type(env, *, dataset):
     try:
         return dataset.score_type_object
     # The score type's constructor is called, which may raise any

cms/service/flushingdict.py

@@ -18,12 +18,11 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import logging
+import time
 
 import gevent
 from gevent.lock import RLock
 
-from cmscommon.datetime import monotonic_time
-
 
 logger = logging.getLogger(__name__)
 
@@ -66,13 +65,13 @@ def __init__(self, size, flush_latency_seconds, callback):
         self.d_lock = RLock()
 
         # Time when an item was last inserted in the dict
-        self.last_insert = monotonic_time()
+        self.last_insert = time.monotonic()
 
     def add(self, key, value):
         logger.debug("Adding item %s", key)
         with self.d_lock:
             self.d[key] = value
-            self.last_insert = monotonic_time()
+            self.last_insert = time.monotonic()
 
     def flush(self):
         logger.debug("Flushing items")
@@ -90,7 +89,7 @@ def _check_flush(self):
         while True:
             while True:
                 with self.d_lock:
-                    since_last_insert = monotonic_time() - self.last_insert
+                    since_last_insert = time.monotonic() - self.last_insert
                     if len(self.d) != 0 and (
                             len(self.d) >= self.size or
                             since_last_insert > self.flush_latency_seconds):

cmscommon/binary.py

@@ -34,8 +34,7 @@ def hex_to_bin(hex):
 
 
 def bin_to_b64(bin):
-    # TODO: use newline=False instead of strip() when we get rid of Python 2.
-    return binascii.b2a_base64(bin).strip().decode('ascii')
+    return binascii.b2a_base64(bin, newline=False).decode('ascii')
 
 
 def b64_to_bin(b64):

cmscommon/commands.py

@@ -18,11 +18,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-try:
-    from shlex import quote
-except ImportError:
-    # Python 2
-    from pipes import quote
+from shlex import quote
 
 
 __all__ = [

cmscommon/datetime.py

@@ -30,8 +30,6 @@
     "get_timezone", "get_system_timezone",
 
     "utc", "local_tz",
-
-    "monotonic_time",
     ]
 
 
@@ -105,59 +103,3 @@ def get_system_timezone():
     if hasattr(local_tz, 'zone'):
         return local_tz.zone
     return local_tz.tzname(make_datetime())
-
-
-if sys.version_info >= (3, 3):
-    def monotonic_time():
-        """Get the number of seconds passed since a fixed past moment.
-
-        A monotonic clock measures the time elapsed since an arbitrary
-        but immutable instant in the past. The value itself has no
-        direct intrinsic meaning but the difference between two such
-        values does, as it is guaranteed to accurately represent the
-        amount of time passed between when those two measurements were
-        taken, no matter the adjustments to the clock that occurred in
-        between.
-
-        return (float): the value of the clock, in seconds.
-
-        """
-        return time.monotonic()
-
-# Taken from http://bugs.python.org/file19461/monotonic.py and
-# http://stackoverflow.com/questions/1205722/how-do-i-get-monotonic-time-durations-in-python
-# and modified.
-else:
-    from ctypes import Structure, c_long, CDLL, c_int, get_errno, POINTER, \
-        pointer
-    from ctypes.util import find_library
-
-    # Raw means it's immune even to NTP time adjustments.
-    CLOCK_MONOTONIC_RAW = 4
-
-    class timespec(Structure):
-        _fields_ = [
-            ('tv_sec', c_long),
-            ('tv_nsec', c_long)
-            ]
-
-    librt_filename = find_library('rt')
-    if not librt_filename:
-        # On Debian Lenny (Python 2.5.2), find_library() is unable
-        # to locate /lib/librt.so.1
-        librt_filename = 'librt.so.1'
-    librt = CDLL(librt_filename, use_errno=True)
-    _clock_gettime = librt.clock_gettime
-    _clock_gettime.argtypes = (c_int, POINTER(timespec))
-
-    def monotonic_time():
-        """Get the number of seconds passed since a fixed past moment.
-
-        return (float): the value of a monotonic clock, in seconds.
-
-        """
-        t = timespec()
-        if _clock_gettime(CLOCK_MONOTONIC_RAW, pointer(t)) != 0:
-            errno_ = get_errno()
-            raise OSError(errno_, os.strerror(errno_))
-        return t.tv_sec + t.tv_nsec / 1e9

cmscommon/importers.py

@@ -51,9 +51,6 @@ def import_testcases_from_zipfile(
             tests = dict()
             # Match input/output file names to testcases' codenames.
             for filename in archive_zfp.namelist():
-                # In py2, filename is either str (if ASCII) or unicode.
-                # Cast it to a consistent type, compatible with py3.
-                filename = str(filename)
                 match = input_re.match(filename)
                 if match:
                     codename = match.group(1)

cmscommon/terminal.py

@@ -59,7 +59,7 @@ def has_color_support(stream):
             # See `man terminfo` for capabilities' names and meanings.
             if curses.tigetnum("colors") > 0:
                 return True
-        # fileno() can raise OSError (since Python 3.3).
+        # fileno() can raise OSError.
         except Exception:
             pass
     return False

cmsranking/Logger.py

@@ -74,7 +74,7 @@ def has_color_support(stream):
             # See `man terminfo` for capabilities' names and meanings.
             if curses.tigetnum("colors") > 0:
                 return True
-        # fileno() can raise OSError (since Python 3.3).
+        # fileno() can raise OSError.
         except Exception:
             pass
     return False