Clean up code

OpenFontFormat/OFF_io_utils.py

@@ -0,0 +1,109 @@
+
+from datetime import datetime, timedelta, timezone
+from types import TracebackType
+from typing import BinaryIO, Callable, List, Optional, Tuple, Type, TypeVar
+
+from io_utils import Parser, read_fixed_point, read_u16, read_u64
+
+def read_fixed(f: BinaryIO) -> float: # 16.16
+	return read_fixed_point(f, 16, 16)
+
+def read_fixed_version(f: BinaryIO) -> float: # Not the same as parse_fixed
+	majorVersion = read_u16(f)
+	minorVersion = read_u16(f)
+	assert minorVersion in [0x0000, 0x1000, 0x5000], f"Invalid fixed minorVersion: {hex(minorVersion)}"
+
+	return majorVersion + minorVersion/0xa000 # will need to change if there are ever any versions with 2 decimal digits
+
+def read_F2DOT14(f: BinaryIO) -> float: # F2DOT14 (2.14)
+	return read_fixed_point(f, 2, 14)
+
+EPOCH = datetime(1904, 1, 1, tzinfo=timezone.utc)
+def read_long_datetime(f: BinaryIO) -> datetime:
+	return EPOCH+timedelta(seconds=read_u64(f))
+
+T = TypeVar('T')
+
+"""
+The following `parse_at_...` functions all modify the tell of f, so it is recommended that you use `SaveTell` to wrap calling these.
+"""
+
+def parse_at_offset(f: BinaryIO, start_tell: int, offset: int, parser: Parser[T], *, zero_is_null:bool=True) -> T:
+	"""
+	Parses a `T` using `parser` at an offset of `offset` from `start_tell`. 
+	
+	If `zero_is_null` is True, then `offset` cannot be 0.
+	Only set `zero_is_null` to False when you are sure that 0 is a valid offset
+	"""
+	if zero_is_null: assert offset != 0, f"Offset was NULL"
+	f.seek(start_tell+offset)
+	return parser(f)
+
+def parse_at_optional_offset(f: BinaryIO, start_tell: int, offset: int, parser: Parser[T]) -> Optional[T]:
+	"""
+	Same as `parse_at_offset`, however if the offset is NULL (0), then None is returned.
+
+	Should not be used when 0 is a valid offset to something.
+	"""
+	if offset == 0: return None
+	return parse_at_offset(f, start_tell, offset, parser, zero_is_null=True)
+
+def parse_at_offsets(f: BinaryIO, start_tell: int, offsets: List[int], parser: Parser[T], *, zero_is_null:bool=True) -> List[T]:
+	return [parse_at_offset(f, start_tell, offset, parser, zero_is_null=zero_is_null) for offset in offsets]
+
+def parse_at_optional_offsets(f: BinaryIO, start_tell: int, offsets: List[int], parser: Parser[T]) -> List[Optional[T]]:
+	return [parse_at_optional_offset(f, start_tell, offset, parser) for offset in offsets]
+
+def parse_at_offsets_using_length(f: BinaryIO, start_tell: int, offsets: List[int], parser: Callable[[BinaryIO, int, int], T], *, zero_is_null:bool=True) -> List[Optional[T]]:
+	"""
+	The length of the returned list will be one less than that of `offsets`, as the last offset is used to calculate the length of the final element.
+
+	`parser` is of the form `(f: BinaryIO, index: int, length: int) -> T`
+	"""
+
+	elements: List[Optional[T]] = []
+	for i, offset in enumerate(offsets[:-1]):
+		length = offsets[i+1]-offset
+		if length == 0:
+			elements.append(None)
+			continue
+
+		elements.append(parse_at_offset(f, start_tell, offset, lambda f: parser(f, i, length), zero_is_null=zero_is_null))
+
+	return elements
+
+def parse_list_at_offset(f: BinaryIO, start_tell: int, offset: int, count: int, parser: Parser[T], *, zero_is_null:bool=True) -> List[T]:
+	"""
+	Parses a continuous list of `T`s with `count` elements.
+	"""
+	return parse_at_offset(f, start_tell, offset, lambda f: [parser(f) for _ in range(count)], zero_is_null=zero_is_null)
+
+def parse_list_and_use_offsets_into(f: BinaryIO, start_tell: int, offsets: list[int], count: int, parser: Parser[T]) -> Tuple[List[T], List[T]]:
+	elements = [(f.tell(), parser(f)) for _ in range(count)]
+	elements_by_offset_into: List[T] = []
+	for offset in offsets:
+		for (offset_into, element) in elements:
+			if offset + start_tell == offset_into:
+				elements_by_offset_into.append(element)
+				break
+		else:
+			assert False, (f"No element with offset {offset} into this list of elements", start_tell, offsets, elements)
+	return elements_by_offset_into, [element for (_, element) in elements]
+
+class SaveTell:
+	"""
+	A context manager that allows operations to be done on a BinaryIO without affecting the tell.
+	"""
+	def __init__(self, f: BinaryIO):
+		self.f = f
+
+	def __enter__(self) -> int:
+		self.tell = self.f.tell()
+		return self.tell
+
+	def __exit__(self, exc_type: Optional[Type[BaseException]], exc_value: Optional[BaseException], exc_tb: Optional[TracebackType]):
+		self.f.seek(self.tell)
+
+
+def null_if_zero(n: int) -> Optional[int]: return n if n else None
+def nulls_if_zero(ns: List[int]) -> List[Optional[int]]: return list(map(null_if_zero, ns))

OpenFontFormat/OpenFont.py

@@ -1,29 +1,15 @@
 from dataclasses import dataclass
-from datetime import datetime, timedelta, timezone
+from datetime import datetime
 from enum import Enum, EnumMeta
 from io import BytesIO
 from math import floor, log2
-from types import TracebackType
+from typing import  Callable, Generic, List, Optional, Tuple, TypeVar, BinaryIO
-from typing import  Callable, Generic, List, Optional, Tuple, Type, TypeVar, BinaryIO, Self
 
+from OFF_io_utils import SaveTell, null_if_zero, parse_at_offset, parse_at_offsets, parse_at_offsets_using_length, parse_at_optional_offset, parse_at_optional_offsets, parse_list_and_use_offsets_into, parse_list_at_offset, read_F2DOT14, read_fixed, read_fixed_version, read_long_datetime
 from abcde import ABD, ABE
-from io_utils import read_ascii, read_fixed_point, read_i16, read_i32, read_i8, read_int, read_pascal_string, read_u16, read_u24, read_u32, read_u64, read_u8
+from io_utils import Parser, is_at_end, len_to_end, read_ascii, read_i16, read_i32, read_i8, read_int, read_pascal_string, read_u16, read_u24, read_u32, read_u64, read_u8
 
-def read_fixed(f: BinaryIO) -> float: # 16.16
+T = TypeVar('T')
-	return read_fixed_point(f, 16, 16)
-
-def read_fixed_version(f: BinaryIO) -> float: # Not the same as parse_fixed
-	majorVersion = read_u16(f)
-	minorVersion = read_u16(f)
-	assert minorVersion in [0x0000, 0x1000, 0x5000], f"Invalid fixed minorVersion: {hex(minorVersion)}"
-
-	return majorVersion + minorVersion/0x1000/10 # will need to change if there are ever any versions with 2 decimal digits
-
-def read_F2DOT14(f: BinaryIO) -> float: # F2DOT14 (2.14)
-	return read_fixed_point(f, 2, 14)
-
-def read_long_datetime(f: BinaryIO) -> datetime:
-	return datetime(1904, 1, 1, tzinfo=timezone.utc)+timedelta(seconds=read_u64(f))
 
 Tag_ = TypeVar('Tag_')
 SomeTag = Callable[[str], Tag_] # If SomeTag is not an EnumMeta, it should throw a ValueError to indicate an invalid tag
@@ -38,11 +24,12 @@ def read_tag_with_conditions(f: BinaryIO, *conditions: Tuple[Callable[[str], boo
 	else:
 		assert False, f"Invalid {umbrellaTagCls.__name__}: '{tag}'"
 
+always: Callable[[str], bool] = lambda _: True
 def read_tag_from_tags(f: BinaryIO, *tagClss: SomeTag[Tag_], umbrellaTagCls: type | SomeTag[Tag_], strict:bool=True) -> Tag_:
 	"""
 	This is meant to be used for when some instances of an Enum are just CC01, CC02, CC03, ...
 	"""
-	return read_tag_with_conditions(f, *[(lambda _: True, tagCls) for tagCls in tagClss], umbrellaTagCls=umbrellaTagCls, strict=strict)
+	return read_tag_with_conditions(f, *[(always, tagCls) for tagCls in tagClss], umbrellaTagCls=umbrellaTagCls, strict=strict)
 
 def read_tag(f: BinaryIO, tagCls: SomeTag[Tag_], *, strict:bool=True) -> Tag_:
 	return read_tag_from_tags(f, tagCls, umbrellaTagCls=tagCls, strict=strict)
@@ -50,9 +37,6 @@ def read_tag(f: BinaryIO, tagCls: SomeTag[Tag_], *, strict:bool=True) -> Tag_:
 ID_ = TypeVar('ID_')
 SomeID = Callable[[int], ID_]
 
-T = TypeVar('T')
-Parser = Callable[[BinaryIO], T]
-
 def read_id_from_ranges(f: BinaryIO, *ranges: Tuple[Optional[int], SomeID[ID_]], umbrellaIdCls: SomeID[ID_], reader: Parser[int]=read_u16) -> ID_: # must be in ascending order
 	assert len(ranges) > 0, f"Must have at least one range"
 	id = reader(f)
@@ -60,67 +44,11 @@ def read_id_from_ranges(f: BinaryIO, *ranges: Tuple[Optional[int], SomeID[ID_]],
 		if num is not None and id > num: continue
 		try: return idCls(id)
 		except ValueError: pass
-	assert False, f"Invalid {umbrellaIdCls.__name__}: {id}"
+	assert False, f"Invalid {umbrellaIdCls.__name__}: {id} (hex: {repr_hex(id, 2)})"
 
 def read_id(f: BinaryIO, idCls: SomeID[ID_], *, reader: Parser[int]=read_u16) -> ID_:
 	return read_id_from_ranges(f, (None, idCls), umbrellaIdCls=idCls, reader=reader)
 
-class SaveTell:
-	def __init__(self, f: BinaryIO):
-		self.f = f
-
-	def __enter__(self) -> int:
-		self.tell = self.f.tell()
-		return self.tell
-
-	def __exit__(self, exc_type: Optional[Type[BaseException]], exc_value: Optional[BaseException], exc_tb: Optional[TracebackType]) -> None:
-		self.f.seek(self.tell)
-
-# The following `parse_at_...` functions all move the BinaryIO away from wherever it was, so use `with SaveTell(f): ...` to save the tell
-
-def parse_at_offset(f: BinaryIO, start_tell: int, offset: int, parser: Parser[T], *, zero_is_null:bool=True) -> T:
-	if zero_is_null: # Some tables have 0 being a valid offset
-		assert offset, f"Offset was NULL"
-	f.seek(start_tell+offset)
-	return parser(f)
-
-def parse_at_optional_offset(f: BinaryIO, start_tell: int, offset: Optional[int], parser: Parser[T], *, zero_is_null:bool=True) -> Optional[T]:
-	if zero_is_null:
-		if not offset: return None
-	else:
-		if offset is None: return None
-	return parse_at_offset(f, start_tell, offset, parser, zero_is_null=zero_is_null)
-
-def parse_at_offsets(f: BinaryIO, start_tell: int, offsets: List[int], parser: Parser[T], *, zero_is_null:bool=True) -> List[T]:
-	return [parse_at_offset(f, start_tell, offset, parser, zero_is_null=zero_is_null) for offset in offsets]
-
-def parse_at_optional_offsets(f: BinaryIO, start_tell: int, offsets: List[int], parser: Parser[T], *, zero_is_null:bool=True) -> List[Optional[T]]:
-	return [parse_at_optional_offset(f, start_tell, offset, parser, zero_is_null=zero_is_null) for offset in offsets]
-
-def parse_at_offsets_using_length(f: BinaryIO, start_tell: int, offsets: List[int], parser: Callable[[BinaryIO, int, int], T], *, zero_is_null:bool=True) -> List[Optional[T]]:
-	"""
-	The length of the returned list will be one less than that of `offsets`, as the last offset is used to calculate the length of the final element.
-
-	`parser` is of the form `(f: BinaryIO, index: int, length: int) -> T`
-	"""
-
-	elements: List[Optional[T]] = []
-	for i, offset in enumerate(offsets[:-1]):
-		length = offsets[i+1]-offset
-		if length == 0:
-			elements.append(None)
-			continue
-
-		elements.append(parse_at_offset(f, start_tell, offset, lambda f: parser(f, i, length), zero_is_null=zero_is_null))
-
-	return elements
-
-def parse_list_at_offset(f: BinaryIO, start_tell: int, offset: int, count: int, parser: Parser[T], *, zero_is_null:bool=True) -> List[T]:
-	return parse_at_offset(f, start_tell, offset, lambda f: [parser(f) for _ in range(count)], zero_is_null=zero_is_null)
-
-def null_if_zero(n: int) -> Optional[int]: return n if n else None
-def nulls_if_zero(ns: List[int]) -> List[Optional[int]]: return list(map(null_if_zero, ns))
-
 @dataclass
 class Table(ABD): pass
 
@@ -165,9 +93,12 @@ class OffsetTable(Table):
 	entrySelector: int
 	rangeShift: int
 
+def repr_hex(value: int, length: int=8) -> str:
+	return f"0x{hex(value)[2:]:0>{length}}"
+
 def parse_offset_table(f: BinaryIO) -> OffsetTable:
 	sfntVersion = read_u32(f)
-	assert sfntVersion in [0x00010000, 0x4F54544F], f"Invalid sfntVersion: 0x{hex(sfntVersion)[2:]:0>8}. Expected 0x00010000 or 0x4F54544F."
+	assert sfntVersion in [0x00010000, 0x4F54544F], f"Invalid sfntVersion: {repr_hex(sfntVersion)}. Expected 0x00010000 or 0x4F54544F."
 	numTables = read_u16(f)
 	searchRange = read_u16(f)
 	entrySelector = read_u16(f)
@@ -175,7 +106,7 @@ def parse_offset_table(f: BinaryIO) -> OffsetTable:
 	assert bin(searchRange).count('1') == 1 # ensure searchRange is a power of 2
 	assert searchRange//16 <= numTables < searchRange//8 # ensure searchRange//16 is largest power of two less than num_tables
 	assert entrySelector == len(bin(searchRange))-7 # ensure entrySelector is the logarithm of searchRange//16
-
+	assert rangeShift == numTables*16-searchRange
 	return OffsetTable(sfntVersion, numTables, searchRange, entrySelector, rangeShift)
 
 class TableTag(Enum):
@@ -197,7 +128,6 @@ class TableTag(Enum):
 	Prep = 'prep'
 	Gasp = 'gasp' # :O
 
-
 	# 5.4 (CFF)
 	...
 
@@ -208,7 +138,7 @@ class TableTag(Enum):
 	# 5.6 (Optional)
 	DSIG = 'DSIG'
 	Hdmx = 'hdmx'
-	Kern = 'Kern'
+	Kern = 'kern'
 	LTSH = 'LTSH'
 	PCLT = 'PCLT'
 	VDMX = 'VDMX'
@@ -254,119 +184,25 @@ def parse_table_directory_entry(f: BinaryIO) -> TableDirectoryEntry:
 	length = read_u32(f)
 	return TableDirectoryEntry(tableTag, checkSum, offset, length)
 
-# TODO: This should just be a dict[TableTag, TableDirectoryEntry]
-@dataclass
-class FontDirectoryByTable:
-	cmap: Optional[TableDirectoryEntry] = None
-	head: Optional[TableDirectoryEntry] = None
-	hhea: Optional[TableDirectoryEntry] = None
-	hmtx: Optional[TableDirectoryEntry] = None
-	maxp: Optional[TableDirectoryEntry] = None
-	name: Optional[TableDirectoryEntry] = None
-	os2 : Optional[TableDirectoryEntry] = None
-	post: Optional[TableDirectoryEntry] = None
-
-	cvt : Optional[TableDirectoryEntry] = None
-	fpgm: Optional[TableDirectoryEntry] = None
-	glyf: Optional[TableDirectoryEntry] = None
-	loca: Optional[TableDirectoryEntry] = None
-	prep: Optional[TableDirectoryEntry] = None
-	gasp: Optional[TableDirectoryEntry] = None
-
-	svg : Optional[TableDirectoryEntry] = None
-
-	DSIG: Optional[TableDirectoryEntry] = None
-	hdmx: Optional[TableDirectoryEntry] = None
-	Kern: Optional[TableDirectoryEntry] = None
-	LTSH: Optional[TableDirectoryEntry] = None
-	PCLT: Optional[TableDirectoryEntry] = None
-	VDMX: Optional[TableDirectoryEntry] = None
-	vhea: Optional[TableDirectoryEntry] = None
-	vmtx: Optional[TableDirectoryEntry] = None
-	COLR: Optional[TableDirectoryEntry] = None
-	CPAL: Optional[TableDirectoryEntry] = None
-
-	BASE: Optional[TableDirectoryEntry] = None
-	GDEF: Optional[TableDirectoryEntry] = None
-	GPOS: Optional[TableDirectoryEntry] = None
-	GSUB: Optional[TableDirectoryEntry] = None
-	JSTF: Optional[TableDirectoryEntry] = None
-	MATH: Optional[TableDirectoryEntry] = None
-
-	avar: Optional[TableDirectoryEntry] = None
-	cvar: Optional[TableDirectoryEntry] = None
-	fvar: Optional[TableDirectoryEntry] = None
-	gvar: Optional[TableDirectoryEntry] = None
-	HVAR: Optional[TableDirectoryEntry] = None
-	MVAR: Optional[TableDirectoryEntry] = None
-	STAT: Optional[TableDirectoryEntry] = None
-	VVAR: Optional[TableDirectoryEntry] = None
-
 @dataclass
 class FontDirectory:
 	offset_table: OffsetTable
 	table_directory: List[TableDirectoryEntry]
 
-	by_table: FontDirectoryByTable
+	def get_entry(self, table_tag: TableTag) -> Optional[TableDirectoryEntry]:
+		for entry in self.table_directory:
+			if entry.tableTag == table_tag:
+				return entry
+		return None
+
+	def has_entry(self, table_tag: TableTag) -> bool:
+		return self.get_entry(table_tag) is not None
 
 def parse_font_directory(f: BinaryIO) -> FontDirectory:
 	offset_table = parse_offset_table(f)
 	table_directory_entries = [parse_table_directory_entry(f) for _ in range(offset_table.numTables)]
 
-	by_table = FontDirectoryByTable()
+	return FontDirectory(offset_table, table_directory_entries)
-
-	for table_directory_entry in table_directory_entries:
-		match table_directory_entry.tableTag:
-			case TableTag.Cmap: by_table.cmap = table_directory_entry
-			case TableTag.Head: by_table.head = table_directory_entry
-			case TableTag.Hhea: by_table.hhea = table_directory_entry
-			case TableTag.Hmtx: by_table.hmtx = table_directory_entry
-			case TableTag.Maxp: by_table.maxp = table_directory_entry
-			case TableTag.Name: by_table.name = table_directory_entry
-			case TableTag.OS2 : by_table.os2  = table_directory_entry
-			case TableTag.Post: by_table.post = table_directory_entry
-
-			case TableTag.Cvt : by_table.cvt  = table_directory_entry
-			case TableTag.Fpgm: by_table.fpgm = table_directory_entry
-			case TableTag.Glyf: by_table.glyf = table_directory_entry
-			case TableTag.Loca: by_table.loca = table_directory_entry
-			case TableTag.Prep: by_table.prep = table_directory_entry
-			case TableTag.Gasp: by_table.gasp = table_directory_entry
-
-			case TableTag.Svg : by_table.svg  = table_directory_entry
-
-			case TableTag.DSIG: by_table.DSIG = table_directory_entry
-			case TableTag.Hdmx: by_table.hdmx = table_directory_entry
-			case TableTag.Kern: by_table.Kern = table_directory_entry
-			case TableTag.LTSH: by_table.LTSH = table_directory_entry
-			case TableTag.PCLT: by_table.PCLT = table_directory_entry
-			case TableTag.VDMX: by_table.VDMX = table_directory_entry
-			case TableTag.Vhea: by_table.vhea = table_directory_entry
-			case TableTag.Vmtx: by_table.vmtx = table_directory_entry
-			case TableTag.COLR: by_table.COLR = table_directory_entry
-			case TableTag.CPAL: by_table.CPAL = table_directory_entry
-
-			case TableTag.BASE: by_table.BASE = table_directory_entry
-			case TableTag.GDEF: by_table.GDEF = table_directory_entry
-			case TableTag.GPOS: by_table.GPOS = table_directory_entry
-			case TableTag.GSUB: by_table.GSUB = table_directory_entry
-			case TableTag.JSTF: by_table.JSTF = table_directory_entry
-			case TableTag.MATH: by_table.MATH = table_directory_entry
-
-			case TableTag.Avar: by_table.avar = table_directory_entry
-			case TableTag.Cvar: by_table.cvar = table_directory_entry
-			case TableTag.Fvar: by_table.fvar = table_directory_entry
-			case TableTag.Gvar: by_table.gvar = table_directory_entry
-			case TableTag.HVAR: by_table.HVAR = table_directory_entry
-			case TableTag.MVAR: by_table.MVAR = table_directory_entry
-			case TableTag.STAT: by_table.STAT = table_directory_entry
-			case TableTag.VVAR: by_table.VVAR = table_directory_entry
-
-			case _:
-				assert False, f"Unimplemented: tableTag: {table_directory_entry.tableTag}"
-
-	return FontDirectory(offset_table, table_directory_entries, by_table)
-
 
 @dataclass
 class CmapSubtable(Table, ABD):
@@ -390,7 +226,7 @@ def parse_sub_header(f: BinaryIO) -> SubHeader:
 @dataclass
 class CmapSubtable_Format_2(CmapSubtable):
 	length: int
-	language: int
+	language: int # TODO: Make this an optional int
 	subHeaderKeys: List[int] # 256 elements
 	subHeaders: List[SubHeader]
 	glyphIndexArray: List[int]
@@ -566,7 +402,9 @@ def parse_cmap_subtable(f: BinaryIO, platformID: PlatformID) -> CmapSubtable:
 			entryCount = read_u16(f)
 			glyphIdArray = [read_u16(f) for _ in range(entryCount)]
 
-			assert f.tell()-start_tell == length, (f.tell()-start_tell, length)
+			assert length-4<f.tell()-start_tell<=length, (f.tell()-start_tell, length)
+			f.seek(length-(f.tell()-start_tell))
+
 			return CmapSubtable_Format_6(format, length, language, firstCode, entryCount, glyphIdArray)
 		case 12:
 			assert read_u16(f) == 0, "Reserved"
@@ -643,6 +481,7 @@ def encoding_ID_cls_from_platform_ID(platformID: PlatformID) -> Callable[[int],
 def parse_encoding_ID(f: BinaryIO, platformID: PlatformID) -> EncodingID:
 	return read_id(f, encoding_ID_cls_from_platform_ID(platformID))
 
+# TODO: Finish this
 def parse_string_with_encoding_ID(f: BinaryIO, length: int, encodingID: EncodingID) -> str:
 	bytes = f.read(length)
 	match encodingID:
@@ -687,6 +526,7 @@ def parse_cmap_table(f: BinaryIO) -> CmapTable:
 
 	return CmapTable(version, numTables, encodingRecords)
 
+HEAD_TABLE_MAGIC = 0x5F0F3CF5
 @dataclass
 class HeadTable(Table):
 	majorVersion: int
@@ -715,7 +555,7 @@ def parse_head_table(f: BinaryIO) -> HeadTable:
 
 	fontRevision = read_fixed(f)
 	checkSumAdjustment = read_u32(f)
-	assert read_u32(f) == 0x5F0F3CF5, "magicNumber"
+	assert read_u32(f) == HEAD_TABLE_MAGIC, "magicNumber"
 	flags = read_u16(f)
 	unitsPerEm = read_u16(f)
 	created = read_long_datetime(f)
@@ -867,6 +707,123 @@ class LanguageID(ABE): pass
 
 class MacintoshLanguageID(LanguageID, Enum):
 	English = 0
+	French = 1
+	German = 2
+	Italian = 3
+	Dutch = 4
+	Swedish = 5
+	Spanish = 6
+	Danish = 7
+	Portuguese = 8
+	Norwegian = 9
+	Hebrew = 10
+	Japanese = 11
+	Arabic = 12
+	Finnish = 13
+	Greek = 14
+	Icelandic = 15
+	Maltese = 16
+	Turkish = 17
+	Croatian = 18
+	Chinese_Traditional = 19
+	Urdu = 20
+	Hindi = 21
+	Thai = 22
+	Korean = 23
+	Lithuanian = 24
+	Polish = 25
+	Hungarian = 26
+	Estonian = 27
+	Latvian = 28
+	Sami = 29
+	Faroese = 30
+	FarsiPersian  = 31
+	Russian = 32
+	Chinese_Simplified = 33
+	Flemish = 34
+	IrishGaelic = 35
+	Albanian = 36
+	Romanian = 37
+	Czech = 38
+	Slovak = 39
+	Slovenian = 40
+	Yiddish = 41
+	Serbian = 42
+	Macedonian = 43
+	Bulgarian = 44
+	Ukrainian = 45
+	Byelorussian = 46
+	Uzbek = 47
+	Kazakh = 48
+	Azerbaijani_CyrillicScript = 49
+	Azerbaijani_ArabicScript = 50
+	Armenian = 51
+	Georgian = 52
+	Moldavian = 53
+	Kirghiz = 54
+	Tajiki = 55
+	Turkmen = 56
+	Mongolian_MongolianScript = 57
+	Mongolian_CyrillicScript = 58
+	Pashto = 59
+	Kurdish = 60
+	Kashmiri = 61
+	Sindhi = 62
+	Tibetan = 63
+	Nepali = 64
+	Sanskrit = 65
+	Marathi = 66
+	Bengali = 67
+	Assamese = 68
+	Gujarati = 69
+	Punjabi = 70
+	Oriya = 71
+	Malayalam = 72
+	Kannada = 73
+	Tamil = 74
+	Telugu = 75
+	Sinhalese = 76
+	Burmese = 77
+	Khmer = 78
+	Lao = 79
+	Vietnamese = 80
+	Indonesian = 81
+	Tagalong = 82
+	Malay_RomanScript = 83
+	Malay_ArabicScript = 84
+	Amharic = 85
+	Tigrinya = 86
+	Galla = 87
+	Somali = 88
+	Swahili = 89
+	Rundi = 91
+	KinyarwandaRuanda = 90
+	NyanjaChewa = 92
+	Malagasy = 93
+	Esperanto = 94
+	Welsh = 128
+	Basque = 129
+	Catalan = 130
+	Latin = 131
+	Quenchua = 132
+	Guarani = 133
+	Aymara = 134
+	Tatar = 135
+	Uighur = 136
+	Dzongkha = 137
+	Javanese_RomanScript = 138
+	Sundanese_RomanScript = 139
+	Galician = 140
+	Afrikaans = 141
+	Breton = 142
+	Inuktitut = 143
+	ScottishGaelic = 144
+	ManxGaelic = 145
+	IrishGaelic_WithDotAbove = 146
+	Tongan = 147
+	Greek_Polytonic = 148
+	Greenlandic = 149
+	Azerbaijani_RomanScript = 150
 
 	def __str__(self) -> str: return self._name_
 
@@ -1175,7 +1132,7 @@ def parse_name_table(f: BinaryIO, length: int) -> NameTable:
 		case _:
 			assert False, f"Unimplemented: format: {format}"
 
-	assert False
+	assert False, format
 
 @dataclass
 class VendorTag:
@@ -1218,6 +1175,10 @@ class OS2Table(Table, ABD):
 	usWinAscent: int
 	usWinDescent: int
 
+	def __post_init__(self):
+		if self.fsSelection & 0x40: assert self.fsSelection & (0b100001) == 0 # bit 6 indicates that the font is regular, and therefore cannot be bold or italic.
+		assert self.fsSelection & 0xfc00 == 0, "reserved"
+
 @dataclass
 class OS2Table_Ver_0(OS2Table): pass
 
@@ -1263,9 +1224,6 @@ def parse_OS2_table(f: BinaryIO) -> OS2Table:
 	sTypoAscender, sTypoDescender, sTypoLineGap = read_i16(f), read_i16(f), read_i16(f)
 	usWinAscent, usWinDescent = read_u16(f), read_u16(f)
 
-	if fsSelection & 0x40: assert fsSelection & (0b100001) == 0 # bit 6 indicates that the font is regular, and therefore cannot be bold or italic.
-	assert fsSelection & 0xfc00 == 0, "reserved"
-
 	if version == 0:
 		return OS2Table_Ver_0(version, xAvgCharWidth, usWeightClass, usWidthClass, fsType, ySubscriptXSize, ySubscriptYSize, ySubscriptXOffset, ySubscriptYOffset, ySuperscriptXSize, ySuperscriptYSize, ySuperscriptXOffset, ySuperscriptYOffset, yStrikeoutSize, yStrikeoutPosition, sFamilyClass, panose, ulUnicodeRange1, ulUnicodeRange2, ulUnicodeRange3, ulUnicodeRange4, achVendID, fsSelection, usFirstCharIndex, usLastCharIndex, sTypoAscender, sTypoDescender, sTypoLineGap, usWinAscent, usWinDescent)
 
@@ -1346,6 +1304,8 @@ def parse_post_table(f: BinaryIO, length: int) -> PostTable:
 			while length - (f.tell() - start_tell) > 0: # kinda dangerous, but I think it's the only way to make it work? number of strings is not necessarily equal to numGlyphs. I think that you could probably figure out the number of strings by filtering elements in the glyphNameIndex array
 				names.append(read_pascal_string(f))
 
+			assert f.tell()-start_tell == length
+			
 			return PostTable_Ver_2_0(version, italicAngle, underlinePosition, underlineThickness, isFixedPitch, minMemType42, maxMemType42, minMemType1, maxMemType1, numGlyphs, glyphNameIndex, names)
 		case 3.0:
 			return PostTable_Ver_3_0(version, italicAngle, underlinePosition, underlineThickness, isFixedPitch, minMemType42, maxMemType42, minMemType1, maxMemType1)
@@ -1414,6 +1374,9 @@ class DSIGTable(Table, ABD):
 	flags: int # It's u16 but only bits 0-7 are documented?
 	signatureRecords: List[SignatureRecord] # there's a typo in the ISO documentation.
 
+	def __post_init__(self):
+		assert self.flags & 0xfe == 0, "Reserved"
+
 @dataclass
 class DSIGTable_Ver_1(DSIGTable): pass
 
@@ -1425,7 +1388,6 @@ def parse_DSIG_table(f: BinaryIO) -> DSIGTable:
 
 	numSignatures = read_u16(f)
 	flags = read_u16(f)
-	assert flags & 0xfe == 0, "Reserved"
 	signatureRecords = [parse_signature_record(f, start_tell) for _ in range(numSignatures)]
 
 	if version == 1:
@@ -1678,14 +1640,18 @@ class CCXXTag(ABE):
 		self.num = int(tag[2:])
 		if not (self.__range__[0] <= self.num <= self.__range__[1]): raise ValueError(f"Invalid {self.__class__.__name__}: {self.num}. Expected number between {self.__range__[0]} and {self.__range__[1]}.")
 
-	@classmethod
+	# @classmethod
-	def from_num(cls, num: int) -> Self:
+	# def from_num(cls, num: int) -> Self:
-		assert 0 <= num <= 99, f"Invalid num: {num}. Must be two digits"
+	# 	assert 0 <= num <= 99, f"Invalid num: {num}. Must be two digits"
-		return cls(f"{cls.__CC__}{num:0>2}") # don't need to check the range because the __init__ will check
+	# 	return cls(f"{cls.__CC__}{num:0>2}") # don't need to check the range because the __init__ will check
 	
 	def __str__(self) -> str:
 		return f"'{self.__CC__}{self.num:0>2}'"
 	
+	@property
+	def name(self) -> str:
+		return str(self)
+
 class ScriptTag(Enum):
 	Adlam = 'adlm'
 	Ahom = 'ahom'
@@ -2475,8 +2441,12 @@ class ValidLangSysTag(LangSysTag, Enum):
 
 	def __str__(self) -> str: return self._name_
 
+@dataclass
+class InvalidLangSysTag(LangSysTag):
+	tag: str
+
 def parse_lang_sys_tag(f: BinaryIO) -> LangSysTag:
-	return read_tag_from_tags(f, ValidLangSysTag, MS_VOLT_Tag, umbrellaTagCls=LangSysTag)
+	return read_tag_from_tags(f, ValidLangSysTag, InvalidLangSysTag, MS_VOLT_Tag, umbrellaTagCls=LangSysTag)
 
 @dataclass
 class LangSysRecord:
@@ -2682,8 +2652,18 @@ class MS_VOLT_Tag(CCXXTag, LangSysTag, FeatureTag):
 	__CC__ = 'zz'
 	__range__ = (0, 99) # I don't know if zz00 is valid or not, but I am letting it be, so that it can be caught, because zzXX is not a valid tag for anything
 
+def is_vendor_feature_tag(tag: str) -> bool:
+	return all(map(is_upper, tag))
+
+@dataclass
+class VendorFeatureTag(FeatureTag):
+	tag: str
+
+	def __post_init__(self):
+		if not is_vendor_feature_tag(self.tag): raise ValueError
+
 def parse_feature_tag(f: BinaryIO) -> FeatureTag:
-	return read_tag_from_tags(f, SimpleFeatureTag, CvXXFeatureTag, SsXXFeatureTag, MS_VOLT_Tag, umbrellaTagCls=FeatureTag)
+	return read_tag_with_conditions(f, (always, SimpleFeatureTag), (always, CvXXFeatureTag), (always, SsXXFeatureTag), (is_vendor_feature_tag, VendorFeatureTag), (lambda s: is_CCXX('zz', s), MS_VOLT_Tag), umbrellaTagCls=FeatureTag)
 
 @dataclass
 class FeatureParamsTable(Table, ABD): pass
@@ -2828,7 +2808,7 @@ class LookupFlag: # TODO: Do this like the other flags
 def parse_lookup_flag(f: BinaryIO) -> LookupFlag:
 	lookupFlag = read_u16(f)
 	rightToLeft, ignoreBaseGlyphs, ignoreLigatures, ignoreMarks, useMarkFilteringSet = [bool(lookupFlag&(1<<i)) for i in range(5)]
-	assert lookupFlag & 0x00e0 == 0, "Reserved"
+	assert lookupFlag & 0x00e0 == 0, "Reserved" # TODO: Once you do this like the other flags, put this in the __post_init__
 	markAttachmentType = (lookupFlag & 0xff00) >> 8
 
 	return LookupFlag(rightToLeft, ignoreBaseGlyphs, ignoreLigatures, ignoreMarks, useMarkFilteringSet, markAttachmentType)
@@ -3091,9 +3071,11 @@ class ValueFormatFlags:
 	def x_advance_device(self) -> bool: 	return (self.bytes & 0x0040)!=0
 	def y_advance_device(self) -> bool: 	return (self.bytes & 0x0080)!=0
 
+	def __post_init__(self):
+		assert self.bytes & 0xFF00 == 0, "Reserved"
+
 def parse_value_format(f: BinaryIO) -> ValueFormatFlags:
 	valueFormat = read_u16(f)
-	assert valueFormat & 0xFF00 == 0, "Reserved"
 
 	return ValueFormatFlags(valueFormat)
 
@@ -3104,12 +3086,18 @@ class DeviceTable(Table):
 	deltaFormat: int
 	deltaValue: List[int]
 
+	def __post_init__(self):
+		assert self.deltaFormat & 0x7ffc == 0, "Reserved"
+
 @dataclass
 class VariationIndexTable(Table):
 	deltaSetOuterIndex: int
 	deltaSetInnerIndex: int
 	deltaFormat: int
 
+	def __post_init__(self):
+		assert self.deltaFormat == 0x8000
+
 DeviceTable_ = DeviceTable | VariationIndexTable
 
 def parse_device_table(f: BinaryIO) -> DeviceTable_:
@@ -3117,7 +3105,6 @@ def parse_device_table(f: BinaryIO) -> DeviceTable_:
 	second = read_u16(f)
 
 	deltaFormat = read_u16(f)
-	assert deltaFormat & 0x7ffc == 0, "Reserved"
 	assert deltaFormat in [1, 2, 3, 0x8000], f"Invalid deltaFormat: {deltaFormat}"
 
 	match deltaFormat:
@@ -3476,10 +3463,10 @@ def parse_value_record(f: BinaryIO, start_tell: int, valueFormat: ValueFormatFla
 	xAdvance = read_i16(f) if valueFormat.x_advance() else None
 	yAdvance = read_i16(f) if valueFormat.y_advance() else None
 
-	xPlaDeviceOffset = read_u16(f) if valueFormat.x_placement_device() else None
+	xPlaDeviceOffset = read_u16(f) if valueFormat.x_placement_device() else 0
-	yPlaDeviceOffset = read_u16(f) if valueFormat.y_placement_device() else None
+	yPlaDeviceOffset = read_u16(f) if valueFormat.y_placement_device() else 0
-	xAdvDeviceOffset = read_u16(f) if valueFormat.x_advance_device() else None
+	xAdvDeviceOffset = read_u16(f) if valueFormat.x_advance_device() else 0
-	yAdvDeviceOffset = read_u16(f) if valueFormat.y_advance_device() else None
+	yAdvDeviceOffset = read_u16(f) if valueFormat.y_advance_device() else 0
 	with SaveTell(f):
 		xPlaDevice = parse_at_optional_offset(f, start_tell, xPlaDeviceOffset, parse_device_table)
 		yPlaDevice = parse_at_optional_offset(f, start_tell, yPlaDeviceOffset, parse_device_table)
@@ -4222,7 +4209,7 @@ def parse_GPOS_table(f: BinaryIO) -> GPOSTable:
 
 	featureVariationsOffset = read_u32(f)
 	with SaveTell(f):
-		featureVariations = parse_at_optional_offset(f, start_tell, featureVariationsOffset, lambda f: parse_feature_variations_table(f, featureList))
+		featureVariations = parse_at_offset(f, start_tell, featureVariationsOffset, lambda f: parse_feature_variations_table(f, featureList))
 	
 	if minorVersion == 1:
 		return GPOSTable_Ver_1_1(majorVersion, minorVersion, scriptList, featureList, lookupList, featureVariations)
@@ -4616,7 +4603,7 @@ def parse_GSUB_lookup_subtable(f: BinaryIO, lookupType: GSUBLookupType) -> GSUBL
 					ligatureSetOffsets = [read_u16(f) for _ in range(ligatureSetCount)]
 					with SaveTell(f):
 						coverage = parse_at_offset(f, start_tell, coverageOffset, parse_coverage_table)
-						ligatureSets = parse_at_offsets(f, start_tell, ligatureSetOffsets, lambda f: parse_set_table(f, parse_ligature_table))
+						ligatureSets = parse_at_offsets(f, start_tell, ligatureSetOffsets, parse_ligature_set_table)
 
 					return LigatureSubstSubtable_Format_1(substFormat, coverage, ligatureSetCount, ligatureSets)
 				case _:
@@ -4764,7 +4751,7 @@ def parse_GSUB_lookup_subtable(f: BinaryIO, lookupType: GSUBLookupType) -> GSUBL
 	assert False, lookupType
 
 @dataclass
-class GSUBTable(Table, ABD):
+class GSUBTable(Table, ABD): # TODO: Maybe make a generic class for this, because this is the same as GPOSTable
 	majorVersion: int
 	minorVersion: int
 	# See: https://github.com/MicrosoftDocs/typography-issues/issues/79
@@ -4869,12 +4856,15 @@ class SimpleGlyphFlag:
 	def y_is_same_or_positive_short(self) -> bool: 	return (self.byte & 0x20)!=0
 	def overlap_simple(self) -> bool: 				return (self.byte & 0x40)!=0
 
-	def __str__(self) -> str:
+	def __repr__(self) -> str:
-		return '0x'+hex(self.byte)[2:].rjust(2, '0')
+		return repr_hex(self.byte, 2)
+	
+	def __post_init__(self):
+		assert self.byte & 0x80 == 0, self
 
 def parse_simple_glyph_flag(f: BinaryIO) -> SimpleGlyphFlag:
 	flags = read_u8(f)
-	assert flags & 0x80 == 0, "reserved"
+
 	return SimpleGlyphFlag(flags)
 	
 @dataclass
@@ -4887,27 +4877,30 @@ class SimpleGlyph(Glyph):
 
 @dataclass
 class CompoundGlyphFlag:
-	byte: int
+	bytes: int
 
-	def arg_1_and_2_are_words(self) -> bool: 		return (self.byte & 0x0001)!=0
+	def arg_1_and_2_are_words(self) -> bool: 		return (self.bytes & 0x0001)!=0
-	def args_are_xy_values(self) -> bool: 			return (self.byte & 0x0002)!=0
+	def args_are_xy_values(self) -> bool: 			return (self.bytes & 0x0002)!=0
-	def round_xy_to_grid(self) -> bool: 			return (self.byte & 0x0004)!=0
+	def round_xy_to_grid(self) -> bool: 			return (self.bytes & 0x0004)!=0
-	def we_have_a_scale(self) -> bool: 				return (self.byte & 0x0008)!=0
+	def we_have_a_scale(self) -> bool: 				return (self.bytes & 0x0008)!=0
-	def more_components(self) -> bool: 				return (self.byte & 0x0020)!=0
+	def more_components(self) -> bool: 				return (self.bytes & 0x0020)!=0
-	def we_have_an_x_and_y_scale(self) -> bool: 	return (self.byte & 0x0040)!=0
+	def we_have_an_x_and_y_scale(self) -> bool: 	return (self.bytes & 0x0040)!=0
-	def we_have_a_two_by_two(self) -> bool: 		return (self.byte & 0x0080)!=0
+	def we_have_a_two_by_two(self) -> bool: 		return (self.bytes & 0x0080)!=0
-	def we_have_instructions(self) -> bool: 		return (self.byte & 0x0100)!=0
+	def we_have_instructions(self) -> bool: 		return (self.bytes & 0x0100)!=0
-	def use_my_metrics(self) -> bool: 				return (self.byte & 0x0200)!=0
+	def use_my_metrics(self) -> bool: 				return (self.bytes & 0x0200)!=0
-	def overlap_compound(self) -> bool: 			return (self.byte & 0x0400)!=0
+	def overlap_compound(self) -> bool: 			return (self.bytes & 0x0400)!=0
-	def scaled_component_offset(self) -> bool: 		return (self.byte & 0x0800)!=0
+	def scaled_component_offset(self) -> bool: 		return (self.bytes & 0x0800)!=0
-	def unscaled_component_offset(self) -> bool: 	return (self.byte & 0x1000)!=0
+	def unscaled_component_offset(self) -> bool: 	return (self.bytes & 0x1000)!=0
 
 	def __repr__(self) -> str:
-		return '0x'+hex(self.byte)[2:].rjust(4, '0')
+		return repr_hex(self.bytes, 4)
+	
+	def __post_init__(self):
+		assert self.bytes & 0xE010 == 0, "Reserved"
 
 def parse_compound_glyph_flag(f: BinaryIO) -> CompoundGlyphFlag:
 	flags = read_u16(f)
-	assert flags & 0xE010 == 0, "reserved"
+
 	return CompoundGlyphFlag(flags)
 
 @dataclass
@@ -4977,7 +4970,6 @@ def parse_simple_glyph_flags(f: BinaryIO, total_points: int) -> Tuple[List[Simpl
 	Returns the logical list (i.e., expanding repeating flags), as well as the total xCoordinates and yCoordinates lengths
 	"""
 	# Mostly just ported from https://github.com/RazrFalcon/ttf-parser/blob/2192d3e496201ab2ff39d5437f88d62e70083f0e/src/tables/glyf.rs#L521
-
 	x_len = 0
 	y_len = 0
 
@@ -5033,8 +5025,9 @@ def parse_glyph(f: BinaryIO, length: int) -> Glyph:
 				case False, False: yDelta = read_i16(yCoordinates)
 
 			coordinates.append((coordinates[-1][0]+xDelta, coordinates[-1][1]+yDelta))
-
+		# TODO: Do I need to read the padding bytes?
 		assert length-4<f.tell()-start_tell<=length # there might be padding bytes
+		assert is_at_end(xCoordinates) and is_at_end(yCoordinates), (len_to_end(xCoordinates), len_to_end(yCoordinates))
 		return SimpleGlyph(numberOfContours, xMin, yMin, xMax, yMax, endPtsOfContours, instructionLength, instructions, flags, coordinates[1:])
 	else:
 		components = [parse_component(f)]
@@ -5091,12 +5084,14 @@ class GaspRange:
 	rangeMaxPPEM: int
 	rangeGaspBehavior: int
 
+	def __post_init__(self):
+		assert self.rangeGaspBehavior & 0xFFF0 == 0, "Reserved"
+
 def parse_gasp_range(f: BinaryIO, version: int) -> GaspRange:
 	rangeMaxPPEM = read_u16(f)
 	rangeGaspBehavior = read_u16(f)
 
 	if version == 0: assert rangeGaspBehavior & 0x000C == 0, "Only supported in version 1"
-	assert rangeGaspBehavior & 0xFFF0 == 0, "Reserved"
 
 	return GaspRange(rangeMaxPPEM, rangeGaspBehavior)
 
@@ -5120,7 +5115,7 @@ class TrueTypeOutlines:
 	control_value_table: Optional[CvtTable]
 	font_program: Optional[FpgmTable]	
 	glyph_data: GlyfTable
-	index_to_location: LocaTable
+	index_to_location: LocaTable # Parsing only
 	CV_program: Optional[PrepTable]
 	grid_fitting_and_scan_conversion: Optional[GaspTable]
 
@@ -5152,9 +5147,11 @@ class TupleIndex:
 
 	def tuple_index(self) -> int: return self.bytes & 0x0fff
 
+	def __post_init__(self):
+		assert self.bytes & 0x1000 == 0, "Reserved"
+
 def parse_tuple_index(f: BinaryIO) -> TupleIndex:
 	tupleIndex = read_u16(f)
-	assert tupleIndex & 0x1000 == 0, "Reserved"
 
 	return TupleIndex(tupleIndex)
 
@@ -5269,7 +5266,7 @@ def parse_cvar_per_tuple_variation_data(f: BinaryIO, tupleVariationHeader: Tuple
 	assert f.tell()-start_tell == tupleVariationHeader.variationDataSize, (f.tell()-start_tell, tupleVariationHeader)
 	return CvarPerTupleVariationData(private_point_numbers, CVT_value_deltas)
 
-def parse_tuple_variation_count(f: BinaryIO) -> Tuple[bool, int]:
+def parse_tuple_variation_count(f: BinaryIO) -> Tuple[bool, int]: # TODO: Maybe do this like the other flags?
 	SHARED_POINT_NUMBERS = 0x8000
 	COUNT_MASK = 0x0fff
 
@@ -5498,6 +5495,9 @@ class VariationAxisRecord:
 	flags: int
 	axisNameID: int
 
+	def __post_init__(self):
+		assert self.flags & 0xfffe == 0, "Reserved"
+
 def parse_variation_axis_record(f: BinaryIO, axisSize: int) -> VariationAxisRecord:
 	start_tell = f.tell()
 
@@ -5506,7 +5506,6 @@ def parse_variation_axis_record(f: BinaryIO, axisSize: int) -> VariationAxisReco
 	defaultValue = read_fixed(f)
 	maxValue = read_fixed(f)
 	flags = read_u16(f)
-	assert flags & 0xfffe == 0, "Reserved"
 	axisNameID = read_u16(f)
 
 	assert f.tell() - start_tell == axisSize, (f.tell() - start_tell, axisSize)
@@ -5608,6 +5607,9 @@ class GvarTable(Table, ABD):
 	flags: int
 	glyphVariationData: List[Optional[GlyphVariationDataTable]]
 
+	def __post_init__(self):
+		assert self.flags & 0xfffe == 0, "Reserved?" # Maybe not?
+
 @dataclass
 class GvarTable_Ver_1_0(GvarTable): pass
 
@@ -5623,8 +5625,7 @@ def parse_gvar_table(f: BinaryIO, glyph_data: GlyfTable) -> GvarTable:
 	sharedTupleCount = read_u16(f)
 	sharedTuplesOffset = read_u32(f)
 	glyphCount = read_u16(f)
-	flags = read_u16(f)
+	flags = read_u16(f) # TODO: Maybe make a method parse_gvar_flags
-	assert flags & 0xfffe == 0, f"Reserved?" # Maybe not?
 	long = (flags & 0x0001) != 0
 	glyphVariationDataArrayOffset = read_u32(f)
 	glyphVariationDataOffsets = [read_u16(f)*2 for _ in range(glyphCount+1)] if not long else [read_u32(f) for _ in range(glyphCount+1)] # TODO: Some of these point to the same GlyphVariationDataTables. Maybe don't reparse each one if it's the same?
@@ -5652,12 +5653,14 @@ class DeltaSetIndexMapTable(Table):
 	mapCount: int
 	mapData: List[Tuple[int, int]] # (outerIndex, innerIndex)
 
+	def __post_init__(self):
+		assert self.entryFormat & 0xffc0 == 0, "Reserved"
+
 def parse_delta_set_index_map_table(f: BinaryIO) -> DeltaSetIndexMapTable:
 	INNER_INDEX_BIT_COUNT_MASK = 0x000f
 	MAP_ENTRY_SIZE_MASK = 0x0030
 
-	entryFormat = read_u16(f)
+	entryFormat = read_u16(f) # TODO: Maybe make all flags like this? If something is reserved, it could just be future things
-	assert entryFormat & 0xffc0 == 0, "Reserved"
 	map_entry_size = ((entryFormat & MAP_ENTRY_SIZE_MASK) >> 4) + 1
 
 	mapCount = read_u16(f)
@@ -5917,78 +5920,80 @@ def possibly_parse_at_table_directory_entry_with_length(f: BinaryIO, table: Opti
 def parse_open_font_file(f: BinaryIO) -> OpenFontFile:
 	font_directory = parse_font_directory(f)
 
-	font_header = parse_at_table_directory_entry(f, font_directory.by_table.head, parse_head_table)
+	font_header = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Head), parse_head_table)
-	horizontal_header = parse_at_table_directory_entry(f, font_directory.by_table.hhea, parse_hhea_table)
+	horizontal_header = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Hhea), parse_hhea_table)
-	maximum_profile = parse_at_table_directory_entry(f, font_directory.by_table.maxp, parse_maxp_table)
+	maximum_profile = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Maxp), parse_maxp_table)
-	horizontal_metrics = parse_at_table_directory_entry(f, font_directory.by_table.hmtx, lambda f: parse_hmtx_table(f, horizontal_header.numberOfHMetrics, maximum_profile.numGlyphs))
+	horizontal_metrics = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Hmtx), lambda f: parse_hmtx_table(f, horizontal_header.numberOfHMetrics, maximum_profile.numGlyphs))
-	naming_table = parse_at_table_directory_entry_with_length(f, font_directory.by_table.name, parse_name_table)
+	naming_table = parse_at_table_directory_entry_with_length(f, font_directory.get_entry(TableTag.Name), parse_name_table)
-	OS2_and_Windows_specific_metrics = parse_at_table_directory_entry(f, font_directory.by_table.os2, parse_OS2_table)
+	OS2_and_Windows_specific_metrics = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.OS2), parse_OS2_table)
-	character_to_glyph_mapping = parse_at_table_directory_entry(f, font_directory.by_table.cmap, parse_cmap_table)
+	character_to_glyph_mapping = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Cmap), parse_cmap_table)
-	PostScript_information = parse_at_table_directory_entry_with_length(f, font_directory.by_table.post, parse_post_table)
+	PostScript_information = parse_at_table_directory_entry_with_length(f, font_directory.get_entry(TableTag.Post), parse_post_table)
 
 	# optional
-	digital_signature = possibly_parse_at_table_directory_entry(f, font_directory.by_table.DSIG, parse_DSIG_table)
+	digital_signature = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.DSIG), parse_DSIG_table)
-	horizontal_device_metrics = possibly_parse_at_table_directory_entry(f, font_directory.by_table.hdmx, lambda f: parse_hdmx_table(f, maximum_profile.numGlyphs))
+	horizontal_device_metrics = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Hdmx), lambda f: parse_hdmx_table(f, maximum_profile.numGlyphs))
-	kerning = possibly_parse_at_table_directory_entry(f, font_directory.by_table.Kern, parse_Kern_table)
+	kerning = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Kern), parse_Kern_table)
-	linear_threshold_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.LTSH, parse_LTSH_table)
+	linear_threshold_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.LTSH), parse_LTSH_table)
-	PCL5_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.PCLT, parse_PCLT_table)
+	PCL5_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.PCLT), parse_PCLT_table)
-	vertical_device_metrics = possibly_parse_at_table_directory_entry(f, font_directory.by_table.VDMX, parse_VDMX_table)
+	vertical_device_metrics = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.VDMX), parse_VDMX_table)
-	vertical_metrics_header = possibly_parse_at_table_directory_entry(f, font_directory.by_table.vhea, parse_vhea_table)
+	vertical_metrics_header = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Vhea), parse_vhea_table)
-	if font_directory.by_table.vmtx:
+	if font_directory.get_entry(TableTag.Vmtx):
 		assert vertical_metrics_header, f"Must have vertical_metrics_header to parse vertical_metrics"
-		vertical_metrics = parse_at_table_directory_entry(f, font_directory.by_table.vmtx, lambda f: parse_vmtx_table(f, vertical_metrics_header.numOfLongVerMetris, maximum_profile.numGlyphs))
+		vertical_metrics = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Vmtx), lambda f: parse_vmtx_table(f, vertical_metrics_header.numOfLongVerMetris, maximum_profile.numGlyphs))
 	else:
 		vertical_metrics = None
-	colour_table = possibly_parse_at_table_directory_entry(f, font_directory.by_table.COLR, parse_COLR_table)
+	colour_table = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.COLR), parse_COLR_table)
-	colour_palette_table = possibly_parse_at_table_directory_entry(f, font_directory.by_table.CPAL, parse_CPAL_table)
+	colour_palette_table = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.CPAL), parse_CPAL_table)
 
 	# TTF / CFF
 	match font_directory.offset_table.sfntVersion:
 		case 0x00010000: # TTF
-			index_to_location = parse_at_table_directory_entry(f, font_directory.by_table.loca, lambda f: parse_loca_table(f, font_header.indexToLocFormat, maximum_profile.numGlyphs))
+			index_to_location = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Loca), lambda f: parse_loca_table(f, font_header.indexToLocFormat, maximum_profile.numGlyphs))
-			glyph_data = parse_at_table_directory_entry(f, font_directory.by_table.glyf, lambda f: parse_glyf_table(f, index_to_location.offsets))
+			glyph_data = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Glyf), lambda f: parse_glyf_table(f, index_to_location.offsets))
 
-			control_value_table = possibly_parse_at_table_directory_entry_with_length(f, font_directory.by_table.cvt, parse_cvt_table)
+			control_value_table = possibly_parse_at_table_directory_entry_with_length(f, font_directory.get_entry(TableTag.Cvt), parse_cvt_table)
-			font_program = possibly_parse_at_table_directory_entry_with_length(f, font_directory.by_table.fpgm, parse_fpgm_table)
+			font_program = possibly_parse_at_table_directory_entry_with_length(f, font_directory.get_entry(TableTag.Fpgm), parse_fpgm_table)
-			CV_program = possibly_parse_at_table_directory_entry_with_length(f, font_directory.by_table.prep, parse_prep_table)
+			CV_program = possibly_parse_at_table_directory_entry_with_length(f, font_directory.get_entry(TableTag.Prep), parse_prep_table)
-			grid_fitting_and_scan_conversion = possibly_parse_at_table_directory_entry(f, font_directory.by_table.gasp, parse_gasp_table)
+			grid_fitting_and_scan_conversion = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Gasp), parse_gasp_table)
 			
 			outlines = TrueTypeOutlines(control_value_table, font_program, glyph_data, index_to_location, CV_program, grid_fitting_and_scan_conversion)
 		case _:
 			assert False, f"Unimplemented: sfntVersion: {hex(font_directory.offset_table.sfntVersion)}"
 
 	# SVG
-	scalar_vector_graphics = possibly_parse_at_table_directory_entry(f, font_directory.by_table.svg, parse_svg_table)
+	scalar_vector_graphics = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Svg), parse_svg_table)
 
 	# Advanced
-	baseline_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.BASE, parse_BASE_table)
+	baseline_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.BASE), parse_BASE_table)
-	glyph_definition_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.GDEF, parse_GDEF_table)
+	glyph_definition_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.GDEF), parse_GDEF_table)
-	glyph_positioning_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.GPOS, parse_GPOS_table)
+	glyph_positioning_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.GPOS), parse_GPOS_table)
-	glyph_substitution_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.GSUB, parse_GSUB_table)
+	glyph_substitution_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.GSUB), parse_GSUB_table)
-	justification_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.JSTF, parse_JSTF_table)
+	justification_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.JSTF), parse_JSTF_table)
-	math_layout_data = possibly_parse_at_table_directory_entry(f, font_directory.by_table.MATH, parse_MATH_table)
+	math_layout_data = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.MATH), parse_MATH_table)
 
 	advanced_features = AdvancedFeatures(baseline_data, glyph_definition_data, glyph_positioning_data, glyph_substitution_data, justification_data, math_layout_data)
 
 	font_variations: Optional[FontVariations] = None
-	if font_directory.by_table.fvar:
+	if font_directory.has_entry(TableTag.Fvar):
-		font_variations_ = parse_at_table_directory_entry(f, font_directory.by_table.fvar, parse_fvar_table)
+		font_variations_ = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Fvar), parse_fvar_table)
-		style_attributes = parse_at_table_directory_entry(f, font_directory.by_table.STAT, parse_STAT_table)
+		style_attributes = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.STAT), parse_STAT_table)
 
-		axis_variations = possibly_parse_at_table_directory_entry(f, font_directory.by_table.avar, parse_avar_table)
+		axis_variations = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Avar), parse_avar_table)
-		if font_directory.by_table.cvar:
+		if font_directory.has_entry(TableTag.Cvar):
-			assert control_value_table, f"Must have control_value_table in order to have CVT_variations!"
+			assert isinstance(outlines, TrueTypeOutlines)
-			CVT_variations = parse_at_table_directory_entry(f, font_directory.by_table.cvar, lambda f: parse_cvar_table(f, font_variations_.axisCount, control_value_table))
+			cvt = outlines.control_value_table
+			assert cvt, f"Must have control_value_table in order to have CVT_variations!"
+			CVT_variations = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Cvar), lambda f: parse_cvar_table(f, font_variations_.axisCount, cvt))
 		else:
 			CVT_variations = None
-		if font_directory.by_table.gvar:
+		if font_directory.has_entry(TableTag.Gvar):
 			assert isinstance(outlines, TrueTypeOutlines)
-			glyph_variations = parse_at_table_directory_entry(f, font_directory.by_table.gvar, lambda f: parse_gvar_table(f, outlines.glyph_data))
+			glyph_variations = parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.Gvar), lambda f: parse_gvar_table(f, outlines.glyph_data))
 		else:
 			glyph_variations = None
-		horizontal_metrics_variations = possibly_parse_at_table_directory_entry(f, font_directory.by_table.HVAR, parse_HVAR_table)
+		horizontal_metrics_variations = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.HVAR), parse_HVAR_table)
-		metrics_variations = possibly_parse_at_table_directory_entry(f, font_directory.by_table.MVAR, parse_MVAR_table)
+		metrics_variations = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.MVAR), parse_MVAR_table)
-		vertical_metrics_variations = possibly_parse_at_table_directory_entry(f, font_directory.by_table.VVAR, parse_VVAR_table)
+		vertical_metrics_variations = possibly_parse_at_table_directory_entry(f, font_directory.get_entry(TableTag.VVAR), parse_VVAR_table)
 
 		font_variations = FontVariations(axis_variations, CVT_variations, font_variations_, glyph_variations, horizontal_metrics_variations, metrics_variations, style_attributes, vertical_metrics_variations)
 	

OpenFontFormat/abcde.py

@@ -1,4 +1,6 @@
-class ABD:
+from abc import ABC
+
+class ABD(ABC):
 	"""
 	#### Abstract Base Dataclass
 
@@ -9,11 +11,14 @@ class ABD:
 			msg = f"Cannot instantiate an Abstract Base Dataclass: {self.__class__.__name__}"
 			raise TypeError(msg)
 
+# TODO: Make a subclass of EnumMeta to do this
 class ABE:
 	"""
 	#### Abstract Base Enum
 	
-	This is for classes that will have an Enum subclass them
+	This is for classes that will have an Enum subclass them.
+
+	Do not implement a __init__ method for the class directly inheriting from ABE
 	"""
 	def __init__(self, *args, **kwargs):
 		if ABE in self.__class__.__bases__ or ABE == self:

OpenFontFormat/io_utils.py

@@ -1,9 +1,23 @@
-from typing import BinaryIO
+from io import SEEK_END
+from typing import BinaryIO, Callable, Literal, TypeVar
 
-ENDIANNESS = 'big'
+def len_to_end(f: BinaryIO) -> int:
+	curr_tell = f.tell()
+	f.seek(0, SEEK_END)
+	end_tell = f.tell()
+	f.seek(curr_tell)
+	return end_tell - curr_tell
 
-def read_int(f: BinaryIO, number: int, signed:bool=False) -> int: return int.from_bytes(f.read(number), ENDIANNESS, signed=signed)
+def is_at_end(f: BinaryIO) -> bool:
-def write_int(f: BinaryIO, value: int, number: int, signed:bool=False) -> int: return f.write(value.to_bytes(number, ENDIANNESS, signed=signed))
+	return len_to_end(f) == 0
+
+ENDIANNESS: Literal['little', 'big'] = 'big'
+
+def read_int_from_bytes(s: bytes, *, signed:bool=False) -> int: return int.from_bytes(s, ENDIANNESS, signed=signed)
+def bytes_from_int(value: int, number: int, *, signed:bool=False) -> bytes: return value.to_bytes(number, ENDIANNESS, signed=signed)
+
+def read_int(f: BinaryIO, number: int, *, signed:bool=False) -> int: return read_int_from_bytes(f.read(number), signed=signed)
+def write_int(f: BinaryIO, value: int, number: int, signed:bool=False) -> int: return f.write(bytes_from_int(value, number, signed=signed))
 
 def read_u64(f: BinaryIO) -> int: return read_int(f, 8)
 def read_u32(f: BinaryIO) -> int: return read_int(f, 4)
@@ -11,7 +25,7 @@ def read_u24(f: BinaryIO) -> int: return read_int(f, 3)
 def read_u16(f: BinaryIO) -> int: return read_int(f, 2)
 def read_u8(f: BinaryIO) -> int: return read_int(f, 1)
 
-def write_u16(f: BinaryIO, value: int) -> int: return f.write(value)
+def write_u16(f: BinaryIO, value: int) -> int: return write_int(f, value, 2)
 
 def read_i32(f: BinaryIO) -> int: return read_int(f, 4, signed=True)
 def read_i16(f: BinaryIO) -> int: return read_int(f, 2, signed=True)
@@ -23,9 +37,12 @@ def read_ascii(f: BinaryIO, number: int) -> str: return f.read(number).decode(en
 def read_fixed_point(f: BinaryIO, preradix_bits: int, postradix_bits:int, *, signed:bool=True) -> float:
 	assert (preradix_bits+postradix_bits)%8 == 0
 	raw = read_int(f, (preradix_bits+postradix_bits)//8, signed=signed)
-	return raw/(1<<(postradix_bits))
+	return raw/(1<<postradix_bits)
 
 def read_pascal_string(f: BinaryIO) -> str:
-	string_size = read_int(f, 1)
+	string_size = read_u8(f)
 	pascal_string = read_ascii(f, string_size)
 	return pascal_string
+
+T = TypeVar('T')
+Parser = Callable[[BinaryIO], T]

OpenFontFormat/test.py

@@ -1,9 +1,9 @@
 #!/usr/bin/env python3
 import os
 import sys
-assert len(sys.argv) == 2, "usage: python3 test.py <test>"
+assert len(sys.argv) >= 2, "usage: python3 test.py <test> [OPTIONS]"
 
-from OpenFont import FontSpecificNameID, NameID, NameTable_Format_0, OpenFontFile, PredefinedNameID, TrueTypeOutlines, open_font_file, write_font_file
+from OpenFont import FontSpecificNameID, NameID, NameTable_Format_0, OpenFontFile, PredefinedNameID, TrueTypeOutlines, open_font_file
 
 def search_names(font: OpenFontFile, nameID: NameID) -> str:
 	assert isinstance(font.naming_table, NameTable_Format_0)
@@ -15,7 +15,7 @@ def search_names(font: OpenFontFile, nameID: NameID) -> str:
 	assert False, f"Name not found: {nameID}"
 
 
-_, test = sys.argv
+_, test, *options = sys.argv
 
 match test:
 	case "names":
@@ -30,11 +30,6 @@ match test:
 				axis_names = [search_names(font, FontSpecificNameID(axis.axisNameID)) for axis in font.font_variations.font_variations.axes]
 				num_instances = font.font_variations.font_variations.instanceCount
 				print(f"\tAxes: [{', '.join(axis_names)}] ({num_instances} instances)")
-	case "rewrite":
-		def test_font(font: OpenFontFile):
-			PATH = "out.ttf"
-			write_font_file(font, PATH)
-			open_font_file(PATH)
 	case _:
 		assert False, f"Invalid test: '{test}'"
 
@@ -44,13 +39,17 @@ if not os.path.exists(COMPLETED_PATH):
 with open(COMPLETED_PATH, "r") as f: completed = f.read().split('\n')
 
 def do_font(file: str):
+	file = file.strip()
 	if file in completed: return
 	try:
 		font = open_font_file(file)
 		test_font(font)
 	except AssertionError as err:
+		if '--raise' in options:
 			err.add_note(f"Failed: {file}")
 			raise err
+		print(f"{file}{':' if '--no-colon' not in options else ''} {err}")
+		return
 	with open(COMPLETED_PATH, 'a') as f: f.write(file+'\n')
 	completed.append(file)
 	
@@ -58,5 +57,3 @@ assert not sys.stdin.isatty(), f"Do not run this program directly, instead pipe
 for line in sys.stdin:
 	file = line.rstrip('\n')
 	do_font(file)
-
-print("Done!")