Rethink container flags design

Author: WyattBlue

av/container/core.pyi

@@ -1,9 +1,9 @@
+from enum import Flag
 from fractions import Fraction
 from pathlib import Path
 from types import TracebackType
-from typing import Any, Callable, Literal, Type, overload
+from typing import Any, Callable, ClassVar, Literal, Type, overload
 
-from av.enum import EnumFlag
 from av.format import ContainerFormat
 
 from .input import InputContainer
@@ -12,22 +12,22 @@ from .streams import StreamContainer
 
 Real = int | float | Fraction
 
-class Flags(EnumFlag):
-    GENPTS: int
-    IGNIDX: int
-    NONBLOCK: int
-    IGNDTS: int
-    NOFILLIN: int
-    NOPARSE: int
-    NOBUFFER: int
-    CUSTOM_IO: int
-    DISCARD_CORRUPT: int
-    FLUSH_PACKETS: int
-    BITEXACT: int
-    SORT_DTS: int
-    FAST_SEEK: int
-    SHORTEST: int
-    AUTO_BSF: int
+class Flags(Flag):
+    gen_pts: ClassVar[Flags]
+    ign_idx: ClassVar[Flags]
+    non_block: ClassVar[Flags]
+    ign_dts: ClassVar[Flags]
+    no_fillin: ClassVar[Flags]
+    no_parse: ClassVar[Flags]
+    no_buffer: ClassVar[Flags]
+    custom_io: ClassVar[Flags]
+    discard_corrupt: ClassVar[Flags]
+    flush_packets: ClassVar[Flags]
+    bitexact: ClassVar[Flags]
+    sort_dts: ClassVar[Flags]
+    fast_seek: ClassVar[Flags]
+    shortest: ClassVar[Flags]
+    auto_bsf: ClassVar[Flags]
 
 class Container:
     writeable: bool
@@ -47,6 +47,7 @@ class Container:
     metadata: dict[str, str]
     open_timeout: Real | None
     read_timeout: Real | None
+    flags: int
 
     def __enter__(self) -> Container: ...
     def __exit__(

av/container/core.pyx

@@ -3,6 +3,7 @@ from libc.stdint cimport int64_t
 
 import os
 import time
+from enum import Flag
 from pathlib import Path
 
 cimport libav as lib
@@ -11,7 +12,6 @@ from av.container.core cimport timeout_info
 from av.container.input cimport InputContainer
 from av.container.output cimport OutputContainer
 from av.container.pyio cimport pyio_close_custom_gil, pyio_close_gil
-from av.enum cimport define_enum
 from av.error cimport err_check, stash_exception
 from av.format cimport build_container_format
 from av.utils cimport avdict_to_dict
@@ -27,14 +27,12 @@ cdef object _cinit_sentinel = object()
 cdef object clock = getattr(time, "monotonic", time.time)
 
 cdef int interrupt_cb (void *p) noexcept nogil:
-
     cdef timeout_info info = dereference(<timeout_info*> p)
     if info.timeout < 0:  # timeout < 0 means no timeout
         return 0
 
     cdef double current_time
     with gil:
-
         current_time = clock()
 
         # Check if the clock has been changed.
@@ -124,47 +122,26 @@ cdef int pyav_io_close_gil(lib.AVFormatContext *s, lib.AVIOContext *pb) noexcept
 
     return result
 
-Flags = define_enum("Flags", __name__, (
-    ("GENPTS", lib.AVFMT_FLAG_GENPTS,
-        "Generate missing pts even if it requires parsing future frames."),
-    ("IGNIDX", lib.AVFMT_FLAG_IGNIDX,
-        "Ignore index."),
-    ("NONBLOCK", lib.AVFMT_FLAG_NONBLOCK,
-        "Do not block when reading packets from input."),
-    ("IGNDTS", lib.AVFMT_FLAG_IGNDTS,
-        "Ignore DTS on frames that contain both DTS & PTS."),
-    ("NOFILLIN", lib.AVFMT_FLAG_NOFILLIN,
-        "Do not infer any values from other values, just return what is stored in the container."),
-    ("NOPARSE", lib.AVFMT_FLAG_NOPARSE,
-        """Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames.
-
-        Also seeking to frames can not work if parsing to find frame boundaries has been disabled."""),
-    ("NOBUFFER", lib.AVFMT_FLAG_NOBUFFER,
-        "Do not buffer frames when possible."),
-    ("CUSTOM_IO", lib.AVFMT_FLAG_CUSTOM_IO,
-        "The caller has supplied a custom AVIOContext, don't avio_close() it."),
-    ("DISCARD_CORRUPT", lib.AVFMT_FLAG_DISCARD_CORRUPT,
-        "Discard frames marked corrupted."),
-    ("FLUSH_PACKETS", lib.AVFMT_FLAG_FLUSH_PACKETS,
-        "Flush the AVIOContext every packet."),
-    ("BITEXACT", lib.AVFMT_FLAG_BITEXACT,
-        """When muxing, try to avoid writing any random/volatile data to the output.
-
-        This includes any random IDs, real-time timestamps/dates, muxer version, etc.
-        This flag is mainly intended for testing."""),
-    ("SORT_DTS", lib.AVFMT_FLAG_SORT_DTS,
-        "Try to interleave outputted packets by dts (using this flag can slow demuxing down)."),
-    ("FAST_SEEK", lib.AVFMT_FLAG_FAST_SEEK,
-        "Enable fast, but inaccurate seeks for some formats."),
-    ("SHORTEST", lib.AVFMT_FLAG_SHORTEST,
-        "Stop muxing when the shortest stream stops."),
-    ("AUTO_BSF", lib.AVFMT_FLAG_AUTO_BSF,
-        "Add bitstream filters as requested by the muxer."),
-), is_flags=True)
 
+class Flags(Flag):
+    gen_pts: "Generate missing pts even if it requires parsing future frames." = lib.AVFMT_FLAG_GENPTS
+    ign_idx: "Ignore index." = lib.AVFMT_FLAG_IGNIDX
+    non_block: "Do not block when reading packets from input." = lib.AVFMT_FLAG_NONBLOCK
+    ign_dts: "Ignore DTS on frames that contain both DTS & PTS." = lib.AVFMT_FLAG_IGNDTS
+    no_fillin: "Do not infer any values from other values, just return what is stored in the container." = lib.AVFMT_FLAG_NOFILLIN
+    no_parse: "Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been disabled." = lib.AVFMT_FLAG_NOPARSE
+    no_buffer: "Do not buffer frames when possible." = lib.AVFMT_FLAG_NOBUFFER
+    custom_io: "The caller has supplied a custom AVIOContext, don't avio_close() it." = lib.AVFMT_FLAG_CUSTOM_IO
+    discard_corrupt: "Discard frames marked corrupted." = lib.AVFMT_FLAG_DISCARD_CORRUPT
+    flush_packets: "Flush the AVIOContext every packet." = lib.AVFMT_FLAG_FLUSH_PACKETS
+    bitexact: "When muxing, try to avoid writing any random/volatile data to the output. This includes any random IDs, real-time timestamps/dates, muxer version, etc. This flag is mainly intended for testing." = lib.AVFMT_FLAG_BITEXACT
+    sort_dts: "Try to interleave outputted packets by dts (using this flag can slow demuxing down)." = lib.AVFMT_FLAG_SORT_DTS
+    fast_seek: "Enable fast, but inaccurate seeks for some formats." = lib.AVFMT_FLAG_FAST_SEEK
+    shortest: "Stop muxing when the shortest stream stops." = lib.AVFMT_FLAG_SHORTEST
+    auto_bsf: "Add bitstream filters as requested by the muxer." = lib.AVFMT_FLAG_AUTO_BSF
 
-cdef class Container:
 
+cdef class Container:
     def __cinit__(self, sentinel, file_, format_name, options,
                   container_options, stream_options,
                   metadata_encoding, metadata_errors,
@@ -248,20 +225,13 @@ cdef class Container:
         cdef lib.AVInputFormat *ifmt
         cdef _Dictionary c_options
         if not self.writeable:
-
             ifmt = self.format.iptr if self.format else NULL
-
             c_options = Dictionary(self.options, self.container_options)
 
             self.set_timeout(self.open_timeout)
             self.start_timeout()
             with nogil:
-                res = lib.avformat_open_input(
-                    &self.ptr,
-                    name,
-                    ifmt,
-                    &c_options.ptr
-                )
+                res = lib.avformat_open_input(&self.ptr, name, ifmt, &c_options.ptr)
             self.set_timeout(None)
             self.err_check(res)
             self.input_was_opened = True
@@ -304,37 +274,16 @@ cdef class Container:
         if self.ptr == NULL:
             raise AssertionError("Container is not open")
 
-    def _get_flags(self):
+    @property
+    def flags(self):
         self._assert_open()
         return self.ptr.flags
 
-    def _set_flags(self, value):
+    @flags.setter
+    def flags(self, int value):
         self._assert_open()
         self.ptr.flags = value
 
-    flags = Flags.property(
-        _get_flags,
-        _set_flags,
-        """Flags property of :class:`.Flags`"""
-    )
-
-    gen_pts = flags.flag_property("GENPTS")
-    ign_idx = flags.flag_property("IGNIDX")
-    non_block = flags.flag_property("NONBLOCK")
-    ign_dts = flags.flag_property("IGNDTS")
-    no_fill_in = flags.flag_property("NOFILLIN")
-    no_parse = flags.flag_property("NOPARSE")
-    no_buffer = flags.flag_property("NOBUFFER")
-    custom_io = flags.flag_property("CUSTOM_IO")
-    discard_corrupt = flags.flag_property("DISCARD_CORRUPT")
-    flush_packets = flags.flag_property("FLUSH_PACKETS")
-    bit_exact = flags.flag_property("BITEXACT")
-    sort_dts = flags.flag_property("SORT_DTS")
-    fast_seek = flags.flag_property("FAST_SEEK")
-    shortest = flags.flag_property("SHORTEST")
-    auto_bsf = flags.flag_property("AUTO_BSF")
-
-
 def open(
     file,
     mode=None,