Source code for fontTools.feaLib.parser

from fontTools.feaLib.error import FeatureLibError
from fontTools.feaLib.lexer import Lexer, IncludingLexer, NonIncludingLexer
from fontTools.misc.encodingTools import getEncoding
from fontTools.misc.py23 import *
import fontTools.feaLib.ast as ast
import logging
import os
import re


log = logging.getLogger(__name__)


[docs]class Parser(object): """Initializes a Parser object. Example: .. code:: python from fontTools.feaLib.parser import Parser parser = Parser(file, font.getReverseGlyphMap()) parsetree = parser.parse() Note: the ``glyphNames`` iterable serves a double role to help distinguish glyph names from ranges in the presence of hyphens and to ensure that glyph names referenced in a feature file are actually part of a font's glyph set. If the iterable is left empty, no glyph name in glyph set checking takes place, and all glyph tokens containing hyphens are treated as literal glyph names, not as ranges. (Adding a space around the hyphen can, in any case, help to disambiguate ranges from glyph names containing hyphens.) By default, the parser will follow ``include()`` statements in the feature file. To turn this off, pass ``followIncludes=False``. Pass a directory string as ``includeDir`` to explicitly declare a directory to search included feature files in. """ extensions = {} ast = ast SS_FEATURE_TAGS = {"ss%02d" % i for i in range(1, 20 + 1)} CV_FEATURE_TAGS = {"cv%02d" % i for i in range(1, 99 + 1)} def __init__( self, featurefile, glyphNames=(), followIncludes=True, includeDir=None, **kwargs ): if "glyphMap" in kwargs: from fontTools.misc.loggingTools import deprecateArgument deprecateArgument("glyphMap", "use 'glyphNames' (iterable) instead") if glyphNames: raise TypeError( "'glyphNames' and (deprecated) 'glyphMap' are " "mutually exclusive" ) glyphNames = kwargs.pop("glyphMap") if kwargs: raise TypeError( "unsupported keyword argument%s: %s" % ("" if len(kwargs) == 1 else "s", ", ".join(repr(k) for k in kwargs)) ) self.glyphNames_ = set(glyphNames) self.doc_ = self.ast.FeatureFile() self.anchors_ = SymbolTable() self.glyphclasses_ = SymbolTable() self.lookups_ = SymbolTable() self.valuerecords_ = SymbolTable() self.symbol_tables_ = {self.anchors_, self.valuerecords_} self.next_token_type_, self.next_token_ = (None, None) self.cur_comments_ = [] self.next_token_location_ = None lexerClass = IncludingLexer if followIncludes else NonIncludingLexer self.lexer_ = lexerClass(featurefile, includeDir=includeDir) self.advance_lexer_(comments=True)
[docs] def parse(self): """Parse the file, and return a :class:`fontTools.feaLib.ast.FeatureFile` object representing the root of the abstract syntax tree containing the parsed contents of the file.""" statements = self.doc_.statements while self.next_token_type_ is not None or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_("include"): statements.append(self.parse_include_()) elif self.cur_token_type_ is Lexer.GLYPHCLASS: statements.append(self.parse_glyphclass_definition_()) elif self.is_cur_keyword_(("anon", "anonymous")): statements.append(self.parse_anonymous_()) elif self.is_cur_keyword_("anchorDef"): statements.append(self.parse_anchordef_()) elif self.is_cur_keyword_("languagesystem"): statements.append(self.parse_languagesystem_()) elif self.is_cur_keyword_("lookup"): statements.append(self.parse_lookup_(vertical=False)) elif self.is_cur_keyword_("markClass"): statements.append(self.parse_markClass_()) elif self.is_cur_keyword_("feature"): statements.append(self.parse_feature_block_()) elif self.is_cur_keyword_("table"): statements.append(self.parse_table_()) elif self.is_cur_keyword_("valueRecordDef"): statements.append(self.parse_valuerecord_definition_(vertical=False)) elif ( self.cur_token_type_ is Lexer.NAME and self.cur_token_ in self.extensions ): statements.append(self.extensions[self.cur_token_](self)) elif self.cur_token_type_ is Lexer.SYMBOL and self.cur_token_ == ";": continue else: raise FeatureLibError( "Expected feature, languagesystem, lookup, markClass, " 'table, or glyph class definition, got {} "{}"'.format( self.cur_token_type_, self.cur_token_ ), self.cur_token_location_, ) return self.doc_
def parse_anchor_(self): # Parses an anchor in any of the four formats given in the feature # file specification (2.e.vii). self.expect_symbol_("<") self.expect_keyword_("anchor") location = self.cur_token_location_ if self.next_token_ == "NULL": # Format D self.expect_keyword_("NULL") self.expect_symbol_(">") return None if self.next_token_type_ == Lexer.NAME: # Format E name = self.expect_name_() anchordef = self.anchors_.resolve(name) if anchordef is None: raise FeatureLibError( 'Unknown anchor "%s"' % name, self.cur_token_location_ ) self.expect_symbol_(">") return self.ast.Anchor( anchordef.x, anchordef.y, name=name, contourpoint=anchordef.contourpoint, xDeviceTable=None, yDeviceTable=None, location=location, ) x, y = self.expect_number_(), self.expect_number_() contourpoint = None if self.next_token_ == "contourpoint": # Format B self.expect_keyword_("contourpoint") contourpoint = self.expect_number_() if self.next_token_ == "<": # Format C xDeviceTable = self.parse_device_() yDeviceTable = self.parse_device_() else: xDeviceTable, yDeviceTable = None, None self.expect_symbol_(">") return self.ast.Anchor( x, y, name=None, contourpoint=contourpoint, xDeviceTable=xDeviceTable, yDeviceTable=yDeviceTable, location=location, ) def parse_anchor_marks_(self): # Parses a sequence of ``[<anchor> mark @MARKCLASS]*.`` anchorMarks = [] # [(self.ast.Anchor, markClassName)*] while self.next_token_ == "<": anchor = self.parse_anchor_() if anchor is None and self.next_token_ != "mark": continue # <anchor NULL> without mark, eg. in GPOS type 5 self.expect_keyword_("mark") markClass = self.expect_markClass_reference_() anchorMarks.append((anchor, markClass)) return anchorMarks def parse_anchordef_(self): # Parses a named anchor definition (`section 2.e.viii <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#2.e.vii>`_). assert self.is_cur_keyword_("anchorDef") location = self.cur_token_location_ x, y = self.expect_number_(), self.expect_number_() contourpoint = None if self.next_token_ == "contourpoint": self.expect_keyword_("contourpoint") contourpoint = self.expect_number_() name = self.expect_name_() self.expect_symbol_(";") anchordef = self.ast.AnchorDefinition( name, x, y, contourpoint=contourpoint, location=location ) self.anchors_.define(name, anchordef) return anchordef def parse_anonymous_(self): # Parses an anonymous data block (`section 10 <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#10>`_). assert self.is_cur_keyword_(("anon", "anonymous")) tag = self.expect_tag_() _, content, location = self.lexer_.scan_anonymous_block(tag) self.advance_lexer_() self.expect_symbol_("}") end_tag = self.expect_tag_() assert tag == end_tag, "bad splitting in Lexer.scan_anonymous_block()" self.expect_symbol_(";") return self.ast.AnonymousBlock(tag, content, location=location) def parse_attach_(self): # Parses a GDEF Attach statement (`section 9.b <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#9.b>`_) assert self.is_cur_keyword_("Attach") location = self.cur_token_location_ glyphs = self.parse_glyphclass_(accept_glyphname=True) contourPoints = {self.expect_number_()} while self.next_token_ != ";": contourPoints.add(self.expect_number_()) self.expect_symbol_(";") return self.ast.AttachStatement(glyphs, contourPoints, location=location) def parse_enumerate_(self, vertical): # Parse an enumerated pair positioning rule (`section 6.b.ii <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#6.b.ii>`_). assert self.cur_token_ in {"enumerate", "enum"} self.advance_lexer_() return self.parse_position_(enumerated=True, vertical=vertical) def parse_GlyphClassDef_(self): # Parses 'GlyphClassDef @BASE, @LIGATURES, @MARKS, @COMPONENTS;' assert self.is_cur_keyword_("GlyphClassDef") location = self.cur_token_location_ if self.next_token_ != ",": baseGlyphs = self.parse_glyphclass_(accept_glyphname=False) else: baseGlyphs = None self.expect_symbol_(",") if self.next_token_ != ",": ligatureGlyphs = self.parse_glyphclass_(accept_glyphname=False) else: ligatureGlyphs = None self.expect_symbol_(",") if self.next_token_ != ",": markGlyphs = self.parse_glyphclass_(accept_glyphname=False) else: markGlyphs = None self.expect_symbol_(",") if self.next_token_ != ";": componentGlyphs = self.parse_glyphclass_(accept_glyphname=False) else: componentGlyphs = None self.expect_symbol_(";") return self.ast.GlyphClassDefStatement( baseGlyphs, markGlyphs, ligatureGlyphs, componentGlyphs, location=location ) def parse_glyphclass_definition_(self): # Parses glyph class definitions such as '@UPPERCASE = [A-Z];' location, name = self.cur_token_location_, self.cur_token_ self.expect_symbol_("=") glyphs = self.parse_glyphclass_(accept_glyphname=False) self.expect_symbol_(";") glyphclass = self.ast.GlyphClassDefinition(name, glyphs, location=location) self.glyphclasses_.define(name, glyphclass) return glyphclass def split_glyph_range_(self, name, location): # Since v1.20, the OpenType Feature File specification allows # for dashes in glyph names. A sequence like "a-b-c-d" could # therefore mean a single glyph whose name happens to be # "a-b-c-d", or it could mean a range from glyph "a" to glyph # "b-c-d", or a range from glyph "a-b" to glyph "c-d", or a # range from glyph "a-b-c" to glyph "d".Technically, this # example could be resolved because the (pretty complex) # definition of glyph ranges renders most of these splits # invalid. But the specification does not say that a compiler # should try to apply such fancy heuristics. To encourage # unambiguous feature files, we therefore try all possible # splits and reject the feature file if there are multiple # splits possible. It is intentional that we don't just emit a # warning; warnings tend to get ignored. To fix the problem, # font designers can trivially add spaces around the intended # split point, and we emit a compiler error that suggests # how exactly the source should be rewritten to make things # unambiguous. parts = name.split("-") solutions = [] for i in range(len(parts)): start, limit = "-".join(parts[0:i]), "-".join(parts[i:]) if start in self.glyphNames_ and limit in self.glyphNames_: solutions.append((start, limit)) if len(solutions) == 1: start, limit = solutions[0] return start, limit elif len(solutions) == 0: raise FeatureLibError( '"%s" is not a glyph in the font, and it can not be split ' "into a range of known glyphs" % name, location, ) else: ranges = " or ".join(['"%s - %s"' % (s, l) for s, l in solutions]) raise FeatureLibError( 'Ambiguous glyph range "%s"; ' "please use %s to clarify what you mean" % (name, ranges), location, ) def parse_glyphclass_(self, accept_glyphname, accept_null=False): # Parses a glyph class, either named or anonymous, or (if # ``bool(accept_glyphname)``) a glyph name. If ``bool(accept_null)`` then # also accept the special NULL glyph. if accept_glyphname and self.next_token_type_ in (Lexer.NAME, Lexer.CID): if accept_null and self.next_token_ == "NULL": # If you want a glyph called NULL, you should escape it. self.advance_lexer_() return self.ast.NullGlyph(location=self.cur_token_location_) glyph = self.expect_glyph_() self.check_glyph_name_in_glyph_set(glyph) return self.ast.GlyphName(glyph, location=self.cur_token_location_) if self.next_token_type_ is Lexer.GLYPHCLASS: self.advance_lexer_() gc = self.glyphclasses_.resolve(self.cur_token_) if gc is None: raise FeatureLibError( "Unknown glyph class @%s" % self.cur_token_, self.cur_token_location_, ) if isinstance(gc, self.ast.MarkClass): return self.ast.MarkClassName(gc, location=self.cur_token_location_) else: return self.ast.GlyphClassName(gc, location=self.cur_token_location_) self.expect_symbol_("[") location = self.cur_token_location_ glyphs = self.ast.GlyphClass(location=location) while self.next_token_ != "]": if self.next_token_type_ is Lexer.NAME: glyph = self.expect_glyph_() location = self.cur_token_location_ if "-" in glyph and self.glyphNames_ and glyph not in self.glyphNames_: start, limit = self.split_glyph_range_(glyph, location) self.check_glyph_name_in_glyph_set(start, limit) glyphs.add_range( start, limit, self.make_glyph_range_(location, start, limit) ) elif self.next_token_ == "-": start = glyph self.expect_symbol_("-") limit = self.expect_glyph_() self.check_glyph_name_in_glyph_set(start, limit) glyphs.add_range( start, limit, self.make_glyph_range_(location, start, limit) ) else: if "-" in glyph and not self.glyphNames_: log.warning( str( FeatureLibError( f"Ambiguous glyph name that looks like a range: {glyph!r}", location, ) ) ) self.check_glyph_name_in_glyph_set(glyph) glyphs.append(glyph) elif self.next_token_type_ is Lexer.CID: glyph = self.expect_glyph_() if self.next_token_ == "-": range_location = self.cur_token_location_ range_start = self.cur_token_ self.expect_symbol_("-") range_end = self.expect_cid_() self.check_glyph_name_in_glyph_set( f"cid{range_start:05d}", f"cid{range_end:05d}", ) glyphs.add_cid_range( range_start, range_end, self.make_cid_range_(range_location, range_start, range_end), ) else: glyph_name = f"cid{self.cur_token_:05d}" self.check_glyph_name_in_glyph_set(glyph_name) glyphs.append(glyph_name) elif self.next_token_type_ is Lexer.GLYPHCLASS: self.advance_lexer_() gc = self.glyphclasses_.resolve(self.cur_token_) if gc is None: raise FeatureLibError( "Unknown glyph class @%s" % self.cur_token_, self.cur_token_location_, ) if isinstance(gc, self.ast.MarkClass): gc = self.ast.MarkClassName(gc, location=self.cur_token_location_) else: gc = self.ast.GlyphClassName(gc, location=self.cur_token_location_) glyphs.add_class(gc) else: raise FeatureLibError( "Expected glyph name, glyph range, " f"or glyph class reference, found {self.next_token_!r}", self.next_token_location_, ) self.expect_symbol_("]") return glyphs def parse_glyph_pattern_(self, vertical): # Parses a glyph pattern, including lookups and context, e.g.:: # # a b # a b c' d e # a b c' lookup ChangeC d e prefix, glyphs, lookups, values, suffix = ([], [], [], [], []) hasMarks = False while self.next_token_ not in {"by", "from", ";", ","}: gc = self.parse_glyphclass_(accept_glyphname=True) marked = False if self.next_token_ == "'": self.expect_symbol_("'") hasMarks = marked = True if marked: if suffix: # makeotf also reports this as an error, while FontForge # silently inserts ' in all the intervening glyphs. # https://github.com/fonttools/fonttools/pull/1096 raise FeatureLibError( "Unsupported contextual target sequence: at most " "one run of marked (') glyph/class names allowed", self.cur_token_location_, ) glyphs.append(gc) elif glyphs: suffix.append(gc) else: prefix.append(gc) if self.is_next_value_(): values.append(self.parse_valuerecord_(vertical)) else: values.append(None) lookuplist = None while self.next_token_ == "lookup": if lookuplist is None: lookuplist = [] self.expect_keyword_("lookup") if not marked: raise FeatureLibError( "Lookups can only follow marked glyphs", self.cur_token_location_, ) lookup_name = self.expect_name_() lookup = self.lookups_.resolve(lookup_name) if lookup is None: raise FeatureLibError( 'Unknown lookup "%s"' % lookup_name, self.cur_token_location_ ) lookuplist.append(lookup) if marked: lookups.append(lookuplist) if not glyphs and not suffix: # eg., "sub f f i by" assert lookups == [] return ([], prefix, [None] * len(prefix), values, [], hasMarks) else: assert not any(values[: len(prefix)]), values format1 = values[len(prefix) :][: len(glyphs)] format2 = values[(len(prefix) + len(glyphs)) :][: len(suffix)] values = ( format2 if format2 and isinstance(format2[0], self.ast.ValueRecord) else format1 ) return (prefix, glyphs, lookups, values, suffix, hasMarks) def parse_chain_context_(self): location = self.cur_token_location_ prefix, glyphs, lookups, values, suffix, hasMarks = self.parse_glyph_pattern_( vertical=False ) chainContext = [(prefix, glyphs, suffix)] hasLookups = any(lookups) while self.next_token_ == ",": self.expect_symbol_(",") ( prefix, glyphs, lookups, values, suffix, hasMarks, ) = self.parse_glyph_pattern_(vertical=False) chainContext.append((prefix, glyphs, suffix)) hasLookups = hasLookups or any(lookups) self.expect_symbol_(";") return chainContext, hasLookups def parse_ignore_(self): # Parses an ignore sub/pos rule. assert self.is_cur_keyword_("ignore") location = self.cur_token_location_ self.advance_lexer_() if self.cur_token_ in ["substitute", "sub"]: chainContext, hasLookups = self.parse_chain_context_() if hasLookups: raise FeatureLibError( 'No lookups can be specified for "ignore sub"', location ) return self.ast.IgnoreSubstStatement(chainContext, location=location) if self.cur_token_ in ["position", "pos"]: chainContext, hasLookups = self.parse_chain_context_() if hasLookups: raise FeatureLibError( 'No lookups can be specified for "ignore pos"', location ) return self.ast.IgnorePosStatement(chainContext, location=location) raise FeatureLibError( 'Expected "substitute" or "position"', self.cur_token_location_ ) def parse_include_(self): assert self.cur_token_ == "include" location = self.cur_token_location_ filename = self.expect_filename_() # self.expect_symbol_(";") return ast.IncludeStatement(filename, location=location) def parse_language_(self): assert self.is_cur_keyword_("language") location = self.cur_token_location_ language = self.expect_language_tag_() include_default, required = (True, False) if self.next_token_ in {"exclude_dflt", "include_dflt"}: include_default = self.expect_name_() == "include_dflt" if self.next_token_ == "required": self.expect_keyword_("required") required = True self.expect_symbol_(";") return self.ast.LanguageStatement( language, include_default, required, location=location ) def parse_ligatureCaretByIndex_(self): assert self.is_cur_keyword_("LigatureCaretByIndex") location = self.cur_token_location_ glyphs = self.parse_glyphclass_(accept_glyphname=True) carets = [self.expect_number_()] while self.next_token_ != ";": carets.append(self.expect_number_()) self.expect_symbol_(";") return self.ast.LigatureCaretByIndexStatement(glyphs, carets, location=location) def parse_ligatureCaretByPos_(self): assert self.is_cur_keyword_("LigatureCaretByPos") location = self.cur_token_location_ glyphs = self.parse_glyphclass_(accept_glyphname=True) carets = [self.expect_number_()] while self.next_token_ != ";": carets.append(self.expect_number_()) self.expect_symbol_(";") return self.ast.LigatureCaretByPosStatement(glyphs, carets, location=location) def parse_lookup_(self, vertical): # Parses a ``lookup`` - either a lookup block, or a lookup reference # inside a feature. assert self.is_cur_keyword_("lookup") location, name = self.cur_token_location_, self.expect_name_() if self.next_token_ == ";": lookup = self.lookups_.resolve(name) if lookup is None: raise FeatureLibError( 'Unknown lookup "%s"' % name, self.cur_token_location_ ) self.expect_symbol_(";") return self.ast.LookupReferenceStatement(lookup, location=location) use_extension = False if self.next_token_ == "useExtension": self.expect_keyword_("useExtension") use_extension = True block = self.ast.LookupBlock(name, use_extension, location=location) self.parse_block_(block, vertical) self.lookups_.define(name, block) return block def parse_lookupflag_(self): # Parses a ``lookupflag`` statement, either specified by number or # in words. assert self.is_cur_keyword_("lookupflag") location = self.cur_token_location_ # format B: "lookupflag 6;" if self.next_token_type_ == Lexer.NUMBER: value = self.expect_number_() self.expect_symbol_(";") return self.ast.LookupFlagStatement(value, location=location) # format A: "lookupflag RightToLeft MarkAttachmentType @M;" value_seen = False value, markAttachment, markFilteringSet = 0, None, None flags = { "RightToLeft": 1, "IgnoreBaseGlyphs": 2, "IgnoreLigatures": 4, "IgnoreMarks": 8, } seen = set() while self.next_token_ != ";": if self.next_token_ in seen: raise FeatureLibError( "%s can be specified only once" % self.next_token_, self.next_token_location_, ) seen.add(self.next_token_) if self.next_token_ == "MarkAttachmentType": self.expect_keyword_("MarkAttachmentType") markAttachment = self.parse_glyphclass_(accept_glyphname=False) elif self.next_token_ == "UseMarkFilteringSet": self.expect_keyword_("UseMarkFilteringSet") markFilteringSet = self.parse_glyphclass_(accept_glyphname=False) elif self.next_token_ in flags: value_seen = True value = value | flags[self.expect_name_()] else: raise FeatureLibError( '"%s" is not a recognized lookupflag' % self.next_token_, self.next_token_location_, ) self.expect_symbol_(";") if not any([value_seen, markAttachment, markFilteringSet]): raise FeatureLibError( "lookupflag must have a value", self.next_token_location_ ) return self.ast.LookupFlagStatement( value, markAttachment=markAttachment, markFilteringSet=markFilteringSet, location=location, ) def parse_markClass_(self): assert self.is_cur_keyword_("markClass") location = self.cur_token_location_ glyphs = self.parse_glyphclass_(accept_glyphname=True) anchor = self.parse_anchor_() name = self.expect_class_name_() self.expect_symbol_(";") markClass = self.doc_.markClasses.get(name) if markClass is None: markClass = self.ast.MarkClass(name) self.doc_.markClasses[name] = markClass self.glyphclasses_.define(name, markClass) mcdef = self.ast.MarkClassDefinition( markClass, anchor, glyphs, location=location ) markClass.addDefinition(mcdef) return mcdef def parse_position_(self, enumerated, vertical): assert self.cur_token_ in {"position", "pos"} if self.next_token_ == "cursive": # GPOS type 3 return self.parse_position_cursive_(enumerated, vertical) elif self.next_token_ == "base": # GPOS type 4 return self.parse_position_base_(enumerated, vertical) elif self.next_token_ == "ligature": # GPOS type 5 return self.parse_position_ligature_(enumerated, vertical) elif self.next_token_ == "mark": # GPOS type 6 return self.parse_position_mark_(enumerated, vertical) location = self.cur_token_location_ prefix, glyphs, lookups, values, suffix, hasMarks = self.parse_glyph_pattern_( vertical ) self.expect_symbol_(";") if any(lookups): # GPOS type 8: Chaining contextual positioning; explicit lookups if any(values): raise FeatureLibError( 'If "lookup" is present, no values must be specified', location ) return self.ast.ChainContextPosStatement( prefix, glyphs, suffix, lookups, location=location ) # Pair positioning, format A: "pos V 10 A -10;" # Pair positioning, format B: "pos V A -20;" if not prefix and not suffix and len(glyphs) == 2 and not hasMarks: if values[0] is None: # Format B: "pos V A -20;" values.reverse() return self.ast.PairPosStatement( glyphs[0], values[0], glyphs[1], values[1], enumerated=enumerated, location=location, ) if enumerated: raise FeatureLibError( '"enumerate" is only allowed with pair positionings', location ) return self.ast.SinglePosStatement( list(zip(glyphs, values)), prefix, suffix, forceChain=hasMarks, location=location, ) def parse_position_cursive_(self, enumerated, vertical): location = self.cur_token_location_ self.expect_keyword_("cursive") if enumerated: raise FeatureLibError( '"enumerate" is not allowed with ' "cursive attachment positioning", location, ) glyphclass = self.parse_glyphclass_(accept_glyphname=True) entryAnchor = self.parse_anchor_() exitAnchor = self.parse_anchor_() self.expect_symbol_(";") return self.ast.CursivePosStatement( glyphclass, entryAnchor, exitAnchor, location=location ) def parse_position_base_(self, enumerated, vertical): location = self.cur_token_location_ self.expect_keyword_("base") if enumerated: raise FeatureLibError( '"enumerate" is not allowed with ' "mark-to-base attachment positioning", location, ) base = self.parse_glyphclass_(accept_glyphname=True) marks = self.parse_anchor_marks_() self.expect_symbol_(";") return self.ast.MarkBasePosStatement(base, marks, location=location) def parse_position_ligature_(self, enumerated, vertical): location = self.cur_token_location_ self.expect_keyword_("ligature") if enumerated: raise FeatureLibError( '"enumerate" is not allowed with ' "mark-to-ligature attachment positioning", location, ) ligatures = self.parse_glyphclass_(accept_glyphname=True) marks = [self.parse_anchor_marks_()] while self.next_token_ == "ligComponent": self.expect_keyword_("ligComponent") marks.append(self.parse_anchor_marks_()) self.expect_symbol_(";") return self.ast.MarkLigPosStatement(ligatures, marks, location=location) def parse_position_mark_(self, enumerated, vertical): location = self.cur_token_location_ self.expect_keyword_("mark") if enumerated: raise FeatureLibError( '"enumerate" is not allowed with ' "mark-to-mark attachment positioning", location, ) baseMarks = self.parse_glyphclass_(accept_glyphname=True) marks = self.parse_anchor_marks_() self.expect_symbol_(";") return self.ast.MarkMarkPosStatement(baseMarks, marks, location=location) def parse_script_(self): assert self.is_cur_keyword_("script") location, script = self.cur_token_location_, self.expect_script_tag_() self.expect_symbol_(";") return self.ast.ScriptStatement(script, location=location) def parse_substitute_(self): assert self.cur_token_ in {"substitute", "sub", "reversesub", "rsub"} location = self.cur_token_location_ reverse = self.cur_token_ in {"reversesub", "rsub"} ( old_prefix, old, lookups, values, old_suffix, hasMarks, ) = self.parse_glyph_pattern_(vertical=False) if any(values): raise FeatureLibError( "Substitution statements cannot contain values", location ) new = [] if self.next_token_ == "by": keyword = self.expect_keyword_("by") while self.next_token_ != ";": gc = self.parse_glyphclass_(accept_glyphname=True, accept_null=True) new.append(gc) elif self.next_token_ == "from": keyword = self.expect_keyword_("from") new = [self.parse_glyphclass_(accept_glyphname=False)] else: keyword = None self.expect_symbol_(";") if len(new) == 0 and not any(lookups): raise FeatureLibError( 'Expected "by", "from" or explicit lookup references', self.cur_token_location_, ) # GSUB lookup type 3: Alternate substitution. # Format: "substitute a from [a.1 a.2 a.3];" if keyword == "from": if reverse: raise FeatureLibError( 'Reverse chaining substitutions do not support "from"', location ) if len(old) != 1 or len(old[0].glyphSet()) != 1: raise FeatureLibError('Expected a single glyph before "from"', location) if len(new) != 1: raise FeatureLibError( 'Expected a single glyphclass after "from"', location ) return self.ast.AlternateSubstStatement( old_prefix, old[0], old_suffix, new[0], location=location ) num_lookups = len([l for l in lookups if l is not None]) is_deletion = False if len(new) == 1 and len(new[0].glyphSet()) == 0: new = [] # Deletion is_deletion = True # GSUB lookup type 1: Single substitution. # Format A: "substitute a by a.sc;" # Format B: "substitute [one.fitted one.oldstyle] by one;" # Format C: "substitute [a-d] by [A.sc-D.sc];" if not reverse and len(old) == 1 and len(new) == 1 and num_lookups == 0: glyphs = list(old[0].glyphSet()) replacements = list(new[0].glyphSet()) if len(replacements) == 1: replacements = replacements * len(glyphs) if len(glyphs) != len(replacements): raise FeatureLibError( 'Expected a glyph class with %d elements after "by", ' "but found a glyph class with %d elements" % (len(glyphs), len(replacements)), location, ) return self.ast.SingleSubstStatement( old, new, old_prefix, old_suffix, forceChain=hasMarks, location=location ) # GSUB lookup type 2: Multiple substitution. # Format: "substitute f_f_i by f f i;" if ( not reverse and len(old) == 1 and len(old[0].glyphSet()) == 1 and ( (len(new) > 1 and max([len(n.glyphSet()) for n in new]) == 1) or len(new) == 0 ) and num_lookups == 0 ): return self.ast.MultipleSubstStatement( old_prefix, tuple(old[0].glyphSet())[0], old_suffix, tuple([list(n.glyphSet())[0] for n in new]), forceChain=hasMarks, location=location, ) # GSUB lookup type 4: Ligature substitution. # Format: "substitute f f i by f_f_i;" if ( not reverse and len(old) > 1 and len(new) == 1 and len(new[0].glyphSet()) == 1 and num_lookups == 0 ): return self.ast.LigatureSubstStatement( old_prefix, old, old_suffix, list(new[0].glyphSet())[0], forceChain=hasMarks, location=location, ) # GSUB lookup type 8: Reverse chaining substitution. if reverse: if len(old) != 1: raise FeatureLibError( "In reverse chaining single substitutions, " "only a single glyph or glyph class can be replaced", location, ) if len(new) != 1: raise FeatureLibError( "In reverse chaining single substitutions, " 'the replacement (after "by") must be a single glyph ' "or glyph class", location, ) if num_lookups != 0: raise FeatureLibError( "Reverse chaining substitutions cannot call named lookups", location ) glyphs = sorted(list(old[0].glyphSet())) replacements = sorted(list(new[0].glyphSet())) if len(replacements) == 1: replacements = replacements * len(glyphs) if len(glyphs) != len(replacements): raise FeatureLibError( 'Expected a glyph class with %d elements after "by", ' "but found a glyph class with %d elements" % (len(glyphs), len(replacements)), location, ) return self.ast.ReverseChainSingleSubstStatement( old_prefix, old_suffix, old, new, location=location ) if len(old) > 1 and len(new) > 1: raise FeatureLibError( "Direct substitution of multiple glyphs by multiple glyphs " "is not supported", location, ) # If there are remaining glyphs to parse, this is an invalid GSUB statement if len(new) != 0 or is_deletion: raise FeatureLibError("Invalid substitution statement", location) # GSUB lookup type 6: Chaining contextual substitution. rule = self.ast.ChainContextSubstStatement( old_prefix, old, old_suffix, lookups, location=location ) return rule def parse_subtable_(self): assert self.is_cur_keyword_("subtable") location = self.cur_token_location_ self.expect_symbol_(";") return self.ast.SubtableStatement(location=location) def parse_size_parameters_(self): # Parses a ``parameters`` statement used in ``size`` features. See # `section 8.b <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#8.b>`_. assert self.is_cur_keyword_("parameters") location = self.cur_token_location_ DesignSize = self.expect_decipoint_() SubfamilyID = self.expect_number_() RangeStart = 0 RangeEnd = 0 if self.next_token_type_ in (Lexer.NUMBER, Lexer.FLOAT) or SubfamilyID != 0: RangeStart = self.expect_decipoint_() RangeEnd = self.expect_decipoint_() self.expect_symbol_(";") return self.ast.SizeParameters( DesignSize, SubfamilyID, RangeStart, RangeEnd, location=location ) def parse_size_menuname_(self): assert self.is_cur_keyword_("sizemenuname") location = self.cur_token_location_ platformID, platEncID, langID, string = self.parse_name_() return self.ast.FeatureNameStatement( "size", platformID, platEncID, langID, string, location=location ) def parse_table_(self): assert self.is_cur_keyword_("table") location, name = self.cur_token_location_, self.expect_tag_() table = self.ast.TableBlock(name, location=location) self.expect_symbol_("{") handler = { "GDEF": self.parse_table_GDEF_, "head": self.parse_table_head_, "hhea": self.parse_table_hhea_, "vhea": self.parse_table_vhea_, "name": self.parse_table_name_, "BASE": self.parse_table_BASE_, "OS/2": self.parse_table_OS_2_, }.get(name) if handler: handler(table) else: raise FeatureLibError( '"table %s" is not supported' % name.strip(), location ) self.expect_symbol_("}") end_tag = self.expect_tag_() if end_tag != name: raise FeatureLibError( 'Expected "%s"' % name.strip(), self.cur_token_location_ ) self.expect_symbol_(";") return table def parse_table_GDEF_(self, table): statements = table.statements while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_("Attach"): statements.append(self.parse_attach_()) elif self.is_cur_keyword_("GlyphClassDef"): statements.append(self.parse_GlyphClassDef_()) elif self.is_cur_keyword_("LigatureCaretByIndex"): statements.append(self.parse_ligatureCaretByIndex_()) elif self.is_cur_keyword_("LigatureCaretByPos"): statements.append(self.parse_ligatureCaretByPos_()) elif self.cur_token_ == ";": continue else: raise FeatureLibError( "Expected Attach, LigatureCaretByIndex, " "or LigatureCaretByPos", self.cur_token_location_, ) def parse_table_head_(self, table): statements = table.statements while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_("FontRevision"): statements.append(self.parse_FontRevision_()) elif self.cur_token_ == ";": continue else: raise FeatureLibError("Expected FontRevision", self.cur_token_location_) def parse_table_hhea_(self, table): statements = table.statements fields = ("CaretOffset", "Ascender", "Descender", "LineGap") while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.cur_token_type_ is Lexer.NAME and self.cur_token_ in fields: key = self.cur_token_.lower() value = self.expect_number_() statements.append( self.ast.HheaField(key, value, location=self.cur_token_location_) ) if self.next_token_ != ";": raise FeatureLibError( "Incomplete statement", self.next_token_location_ ) elif self.cur_token_ == ";": continue else: raise FeatureLibError( "Expected CaretOffset, Ascender, " "Descender or LineGap", self.cur_token_location_, ) def parse_table_vhea_(self, table): statements = table.statements fields = ("VertTypoAscender", "VertTypoDescender", "VertTypoLineGap") while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.cur_token_type_ is Lexer.NAME and self.cur_token_ in fields: key = self.cur_token_.lower() value = self.expect_number_() statements.append( self.ast.VheaField(key, value, location=self.cur_token_location_) ) if self.next_token_ != ";": raise FeatureLibError( "Incomplete statement", self.next_token_location_ ) elif self.cur_token_ == ";": continue else: raise FeatureLibError( "Expected VertTypoAscender, " "VertTypoDescender or VertTypoLineGap", self.cur_token_location_, ) def parse_table_name_(self, table): statements = table.statements while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_("nameid"): statement = self.parse_nameid_() if statement: statements.append(statement) elif self.cur_token_ == ";": continue else: raise FeatureLibError("Expected nameid", self.cur_token_location_) def parse_name_(self): """Parses a name record. See `section 9.e <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#9.e>`_.""" platEncID = None langID = None if self.next_token_type_ in Lexer.NUMBERS: platformID = self.expect_any_number_() location = self.cur_token_location_ if platformID not in (1, 3): raise FeatureLibError("Expected platform id 1 or 3", location) if self.next_token_type_ in Lexer.NUMBERS: platEncID = self.expect_any_number_() langID = self.expect_any_number_() else: platformID = 3 location = self.cur_token_location_ if platformID == 1: # Macintosh platEncID = platEncID or 0 # Roman langID = langID or 0 # English else: # 3, Windows platEncID = platEncID or 1 # Unicode langID = langID or 0x0409 # English string = self.expect_string_() self.expect_symbol_(";") encoding = getEncoding(platformID, platEncID, langID) if encoding is None: raise FeatureLibError("Unsupported encoding", location) unescaped = self.unescape_string_(string, encoding) return platformID, platEncID, langID, unescaped def parse_nameid_(self): assert self.cur_token_ == "nameid", self.cur_token_ location, nameID = self.cur_token_location_, self.expect_any_number_() if nameID > 32767: raise FeatureLibError( "Name id value cannot be greater than 32767", self.cur_token_location_ ) if 1 <= nameID <= 6: log.warning( "Name id %d cannot be set from the feature file. " "Ignoring record" % nameID ) self.parse_name_() # skip to the next record return None platformID, platEncID, langID, string = self.parse_name_() return self.ast.NameRecord( nameID, platformID, platEncID, langID, string, location=location ) def unescape_string_(self, string, encoding): if encoding == "utf_16_be": s = re.sub(r"\\[0-9a-fA-F]{4}", self.unescape_unichr_, string) else: unescape = lambda m: self.unescape_byte_(m, encoding) s = re.sub(r"\\[0-9a-fA-F]{2}", unescape, string) # We now have a Unicode string, but it might contain surrogate pairs. # We convert surrogates to actual Unicode by round-tripping through # Python's UTF-16 codec in a special mode. utf16 = tobytes(s, "utf_16_be", "surrogatepass") return tounicode(utf16, "utf_16_be") @staticmethod def unescape_unichr_(match): n = match.group(0)[1:] return unichr(int(n, 16)) @staticmethod def unescape_byte_(match, encoding): n = match.group(0)[1:] return bytechr(int(n, 16)).decode(encoding) def parse_table_BASE_(self, table): statements = table.statements while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_("HorizAxis.BaseTagList"): horiz_bases = self.parse_base_tag_list_() elif self.is_cur_keyword_("HorizAxis.BaseScriptList"): horiz_scripts = self.parse_base_script_list_(len(horiz_bases)) statements.append( self.ast.BaseAxis( horiz_bases, horiz_scripts, False, location=self.cur_token_location_, ) ) elif self.is_cur_keyword_("VertAxis.BaseTagList"): vert_bases = self.parse_base_tag_list_() elif self.is_cur_keyword_("VertAxis.BaseScriptList"): vert_scripts = self.parse_base_script_list_(len(vert_bases)) statements.append( self.ast.BaseAxis( vert_bases, vert_scripts, True, location=self.cur_token_location_, ) ) elif self.cur_token_ == ";": continue def parse_table_OS_2_(self, table): statements = table.statements numbers = ( "FSType", "TypoAscender", "TypoDescender", "TypoLineGap", "winAscent", "winDescent", "XHeight", "CapHeight", "WeightClass", "WidthClass", "LowerOpSize", "UpperOpSize", ) ranges = ("UnicodeRange", "CodePageRange") while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.cur_token_type_ is Lexer.NAME: key = self.cur_token_.lower() value = None if self.cur_token_ in numbers: value = self.expect_number_() elif self.is_cur_keyword_("Panose"): value = [] for i in range(10): value.append(self.expect_number_()) elif self.cur_token_ in ranges: value = [] while self.next_token_ != ";": value.append(self.expect_number_()) elif self.is_cur_keyword_("Vendor"): value = self.expect_string_() statements.append( self.ast.OS2Field(key, value, location=self.cur_token_location_) ) elif self.cur_token_ == ";": continue def parse_base_tag_list_(self): # Parses BASE table entries. (See `section 9.a <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#9.a>`_) assert self.cur_token_ in ( "HorizAxis.BaseTagList", "VertAxis.BaseTagList", ), self.cur_token_ bases = [] while self.next_token_ != ";": bases.append(self.expect_script_tag_()) self.expect_symbol_(";") return bases def parse_base_script_list_(self, count): assert self.cur_token_ in ( "HorizAxis.BaseScriptList", "VertAxis.BaseScriptList", ), self.cur_token_ scripts = [(self.parse_base_script_record_(count))] while self.next_token_ == ",": self.expect_symbol_(",") scripts.append(self.parse_base_script_record_(count)) self.expect_symbol_(";") return scripts def parse_base_script_record_(self, count): script_tag = self.expect_script_tag_() base_tag = self.expect_script_tag_() coords = [self.expect_number_() for i in range(count)] return script_tag, base_tag, coords def parse_device_(self): result = None self.expect_symbol_("<") self.expect_keyword_("device") if self.next_token_ == "NULL": self.expect_keyword_("NULL") else: result = [(self.expect_number_(), self.expect_number_())] while self.next_token_ == ",": self.expect_symbol_(",") result.append((self.expect_number_(), self.expect_number_())) result = tuple(result) # make it hashable self.expect_symbol_(">") return result def is_next_value_(self): return self.next_token_type_ is Lexer.NUMBER or self.next_token_ == "<" def parse_valuerecord_(self, vertical): if self.next_token_type_ is Lexer.NUMBER: number, location = self.expect_number_(), self.cur_token_location_ if vertical: val = self.ast.ValueRecord( yAdvance=number, vertical=vertical, location=location ) else: val = self.ast.ValueRecord( xAdvance=number, vertical=vertical, location=location ) return val self.expect_symbol_("<") location = self.cur_token_location_ if self.next_token_type_ is Lexer.NAME: name = self.expect_name_() if name == "NULL": self.expect_symbol_(">") return self.ast.ValueRecord() vrd = self.valuerecords_.resolve(name) if vrd is None: raise FeatureLibError( 'Unknown valueRecordDef "%s"' % name, self.cur_token_location_ ) value = vrd.value xPlacement, yPlacement = (value.xPlacement, value.yPlacement) xAdvance, yAdvance = (value.xAdvance, value.yAdvance) else: xPlacement, yPlacement, xAdvance, yAdvance = ( self.expect_number_(), self.expect_number_(), self.expect_number_(), self.expect_number_(), ) if self.next_token_ == "<": xPlaDevice, yPlaDevice, xAdvDevice, yAdvDevice = ( self.parse_device_(), self.parse_device_(), self.parse_device_(), self.parse_device_(), ) allDeltas = sorted( [ delta for size, delta in (xPlaDevice if xPlaDevice else ()) + (yPlaDevice if yPlaDevice else ()) + (xAdvDevice if xAdvDevice else ()) + (yAdvDevice if yAdvDevice else ()) ] ) if allDeltas[0] < -128 or allDeltas[-1] > 127: raise FeatureLibError( "Device value out of valid range (-128..127)", self.cur_token_location_, ) else: xPlaDevice, yPlaDevice, xAdvDevice, yAdvDevice = (None, None, None, None) self.expect_symbol_(">") return self.ast.ValueRecord( xPlacement, yPlacement, xAdvance, yAdvance, xPlaDevice, yPlaDevice, xAdvDevice, yAdvDevice, vertical=vertical, location=location, ) def parse_valuerecord_definition_(self, vertical): # Parses a named value record definition. (See section `2.e.v <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#2.e.v>`_) assert self.is_cur_keyword_("valueRecordDef") location = self.cur_token_location_ value = self.parse_valuerecord_(vertical) name = self.expect_name_() self.expect_symbol_(";") vrd = self.ast.ValueRecordDefinition(name, value, location=location) self.valuerecords_.define(name, vrd) return vrd def parse_languagesystem_(self): assert self.cur_token_ == "languagesystem" location = self.cur_token_location_ script = self.expect_script_tag_() language = self.expect_language_tag_() self.expect_symbol_(";") return self.ast.LanguageSystemStatement(script, language, location=location) def parse_feature_block_(self): assert self.cur_token_ == "feature" location = self.cur_token_location_ tag = self.expect_tag_() vertical = tag in {"vkrn", "vpal", "vhal", "valt"} stylisticset = None cv_feature = None size_feature = False if tag in self.SS_FEATURE_TAGS: stylisticset = tag elif tag in self.CV_FEATURE_TAGS: cv_feature = tag elif tag == "size": size_feature = True use_extension = False if self.next_token_ == "useExtension": self.expect_keyword_("useExtension") use_extension = True block = self.ast.FeatureBlock( tag, use_extension=use_extension, location=location ) self.parse_block_(block, vertical, stylisticset, size_feature, cv_feature) return block def parse_feature_reference_(self): assert self.cur_token_ == "feature", self.cur_token_ location = self.cur_token_location_ featureName = self.expect_tag_() self.expect_symbol_(";") return self.ast.FeatureReferenceStatement(featureName, location=location) def parse_featureNames_(self, tag): """Parses a ``featureNames`` statement found in stylistic set features. See section `8.c <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#8.c>`_.""" assert self.cur_token_ == "featureNames", self.cur_token_ block = self.ast.NestedBlock( tag, self.cur_token_, location=self.cur_token_location_ ) self.expect_symbol_("{") for symtab in self.symbol_tables_: symtab.enter_scope() while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: block.statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_("name"): location = self.cur_token_location_ platformID, platEncID, langID, string = self.parse_name_() block.statements.append( self.ast.FeatureNameStatement( tag, platformID, platEncID, langID, string, location=location ) ) elif self.cur_token_ == ";": continue else: raise FeatureLibError('Expected "name"', self.cur_token_location_) self.expect_symbol_("}") for symtab in self.symbol_tables_: symtab.exit_scope() self.expect_symbol_(";") return block def parse_cvParameters_(self, tag): # Parses a ``cvParameters`` block found in Character Variant features. # See section `8.d <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#8.d>`_. assert self.cur_token_ == "cvParameters", self.cur_token_ block = self.ast.NestedBlock( tag, self.cur_token_, location=self.cur_token_location_ ) self.expect_symbol_("{") for symtab in self.symbol_tables_: symtab.enter_scope() statements = block.statements while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_( { "FeatUILabelNameID", "FeatUITooltipTextNameID", "SampleTextNameID", "ParamUILabelNameID", } ): statements.append(self.parse_cvNameIDs_(tag, self.cur_token_)) elif self.is_cur_keyword_("Character"): statements.append(self.parse_cvCharacter_(tag)) elif self.cur_token_ == ";": continue else: raise FeatureLibError( "Expected statement: got {} {}".format( self.cur_token_type_, self.cur_token_ ), self.cur_token_location_, ) self.expect_symbol_("}") for symtab in self.symbol_tables_: symtab.exit_scope() self.expect_symbol_(";") return block def parse_cvNameIDs_(self, tag, block_name): assert self.cur_token_ == block_name, self.cur_token_ block = self.ast.NestedBlock(tag, block_name, location=self.cur_token_location_) self.expect_symbol_("{") for symtab in self.symbol_tables_: symtab.enter_scope() while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: block.statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.is_cur_keyword_("name"): location = self.cur_token_location_ platformID, platEncID, langID, string = self.parse_name_() block.statements.append( self.ast.CVParametersNameStatement( tag, platformID, platEncID, langID, string, block_name, location=location, ) ) elif self.cur_token_ == ";": continue else: raise FeatureLibError('Expected "name"', self.cur_token_location_) self.expect_symbol_("}") for symtab in self.symbol_tables_: symtab.exit_scope() self.expect_symbol_(";") return block def parse_cvCharacter_(self, tag): assert self.cur_token_ == "Character", self.cur_token_ location, character = self.cur_token_location_, self.expect_any_number_() self.expect_symbol_(";") if not (0xFFFFFF >= character >= 0): raise FeatureLibError( "Character value must be between " "{:#x} and {:#x}".format(0, 0xFFFFFF), location, ) return self.ast.CharacterStatement(character, tag, location=location) def parse_FontRevision_(self): # Parses a ``FontRevision`` statement found in the head table. See # `section 9.c <https://adobe-type-tools.github.io/afdko/OpenTypeFeatureFileSpecification.html#9.c>`_. assert self.cur_token_ == "FontRevision", self.cur_token_ location, version = self.cur_token_location_, self.expect_float_() self.expect_symbol_(";") if version <= 0: raise FeatureLibError("Font revision numbers must be positive", location) return self.ast.FontRevisionStatement(version, location=location) def parse_block_( self, block, vertical, stylisticset=None, size_feature=False, cv_feature=None ): self.expect_symbol_("{") for symtab in self.symbol_tables_: symtab.enter_scope() statements = block.statements while self.next_token_ != "}" or self.cur_comments_: self.advance_lexer_(comments=True) if self.cur_token_type_ is Lexer.COMMENT: statements.append( self.ast.Comment(self.cur_token_, location=self.cur_token_location_) ) elif self.cur_token_type_ is Lexer.GLYPHCLASS: statements.append(self.parse_glyphclass_definition_()) elif self.is_cur_keyword_("anchorDef"): statements.append(self.parse_anchordef_()) elif self.is_cur_keyword_({"enum", "enumerate"}): statements.append(self.parse_enumerate_(vertical=vertical)) elif self.is_cur_keyword_("feature"): statements.append(self.parse_feature_reference_()) elif self.is_cur_keyword_("ignore"): statements.append(self.parse_ignore_()) elif self.is_cur_keyword_("language"): statements.append(self.parse_language_()) elif self.is_cur_keyword_("lookup"): statements.append(self.parse_lookup_(vertical)) elif self.is_cur_keyword_("lookupflag"): statements.append(self.parse_lookupflag_()) elif self.is_cur_keyword_("markClass"): statements.append(self.parse_markClass_()) elif self.is_cur_keyword_({"pos", "position"}): statements.append( self.parse_position_(enumerated=False, vertical=vertical) ) elif self.is_cur_keyword_("script"): statements.append(self.parse_script_()) elif self.is_cur_keyword_({"sub", "substitute", "rsub", "reversesub"}): statements.append(self.parse_substitute_()) elif self.is_cur_keyword_("subtable"): statements.append(self.parse_subtable_()) elif self.is_cur_keyword_("valueRecordDef"): statements.append(self.parse_valuerecord_definition_(vertical)) elif stylisticset and self.is_cur_keyword_("featureNames"): statements.append(self.parse_featureNames_(stylisticset)) elif cv_feature and self.is_cur_keyword_("cvParameters"): statements.append(self.parse_cvParameters_(cv_feature)) elif size_feature and self.is_cur_keyword_("parameters"): statements.append(self.parse_size_parameters_()) elif size_feature and self.is_cur_keyword_("sizemenuname"): statements.append(self.parse_size_menuname_()) elif ( self.cur_token_type_ is Lexer.NAME and self.cur_token_ in self.extensions ): statements.append(self.extensions[self.cur_token_](self)) elif self.cur_token_ == ";": continue else: raise FeatureLibError( "Expected glyph class definition or statement: got {} {}".format( self.cur_token_type_, self.cur_token_ ), self.cur_token_location_, ) self.expect_symbol_("}") for symtab in self.symbol_tables_: symtab.exit_scope() name = self.expect_name_() if name != block.name.strip(): raise FeatureLibError( 'Expected "%s"' % block.name.strip(), self.cur_token_location_ ) self.expect_symbol_(";") # A multiple substitution may have a single destination, in which case # it will look just like a single substitution. So if there are both # multiple and single substitutions, upgrade all the single ones to # multiple substitutions. # Check if we have a mix of non-contextual singles and multiples. has_single = False has_multiple = False for s in statements: if isinstance(s, self.ast.SingleSubstStatement): has_single = not any([s.prefix, s.suffix, s.forceChain]) elif isinstance(s, self.ast.MultipleSubstStatement): has_multiple = not any([s.prefix, s.suffix, s.forceChain]) # Upgrade all single substitutions to multiple substitutions. if has_single and has_multiple: statements = [] for s in block.statements: if isinstance(s, self.ast.SingleSubstStatement): glyphs = s.glyphs[0].glyphSet() replacements = s.replacements[0].glyphSet() if len(replacements) == 1: replacements *= len(glyphs) for i, glyph in enumerate(glyphs): statements.append( self.ast.MultipleSubstStatement( s.prefix, glyph, s.suffix, [replacements[i]], s.forceChain, location=s.location, ) ) else: statements.append(s) block.statements = statements def is_cur_keyword_(self, k): if self.cur_token_type_ is Lexer.NAME: if isinstance(k, type("")): # basestring is gone in Python3 return self.cur_token_ == k else: return self.cur_token_ in k return False def expect_class_name_(self): self.advance_lexer_() if self.cur_token_type_ is not Lexer.GLYPHCLASS: raise FeatureLibError("Expected @NAME", self.cur_token_location_) return self.cur_token_ def expect_cid_(self): self.advance_lexer_() if self.cur_token_type_ is Lexer.CID: return self.cur_token_ raise FeatureLibError("Expected a CID", self.cur_token_location_) def expect_filename_(self): self.advance_lexer_() if self.cur_token_type_ is not Lexer.FILENAME: raise FeatureLibError("Expected file name", self.cur_token_location_) return self.cur_token_ def expect_glyph_(self): self.advance_lexer_() if self.cur_token_type_ is Lexer.NAME: self.cur_token_ = self.cur_token_.lstrip("\\") if len(self.cur_token_) > 63: raise FeatureLibError( "Glyph names must not be longer than 63 characters", self.cur_token_location_, ) return self.cur_token_ elif self.cur_token_type_ is Lexer.CID: return "cid%05d" % self.cur_token_ raise FeatureLibError("Expected a glyph name or CID", self.cur_token_location_) def check_glyph_name_in_glyph_set(self, *names): """Raises if glyph name (just `start`) or glyph names of a range (`start` and `end`) are not in the glyph set. If no glyph set is present, does nothing. """ if self.glyphNames_: missing = [name for name in names if name not in self.glyphNames_] if missing: raise FeatureLibError( "The following glyph names are referenced but are missing from the " f"glyph set: {', '.join(missing)}", self.cur_token_location_, ) def expect_markClass_reference_(self): name = self.expect_class_name_() mc = self.glyphclasses_.resolve(name) if mc is None: raise FeatureLibError( "Unknown markClass @%s" % name, self.cur_token_location_ ) if not isinstance(mc, self.ast.MarkClass): raise FeatureLibError( "@%s is not a markClass" % name, self.cur_token_location_ ) return mc def expect_tag_(self): self.advance_lexer_() if self.cur_token_type_ is not Lexer.NAME: raise FeatureLibError("Expected a tag", self.cur_token_location_) if len(self.cur_token_) > 4: raise FeatureLibError( "Tags can not be longer than 4 characters", self.cur_token_location_ ) return (self.cur_token_ + " ")[:4] def expect_script_tag_(self): tag = self.expect_tag_() if tag == "dflt": raise FeatureLibError( '"dflt" is not a valid script tag; use "DFLT" instead', self.cur_token_location_, ) return tag def expect_language_tag_(self): tag = self.expect_tag_() if tag == "DFLT": raise FeatureLibError( '"DFLT" is not a valid language tag; use "dflt" instead', self.cur_token_location_, ) return tag def expect_symbol_(self, symbol): self.advance_lexer_() if self.cur_token_type_ is Lexer.SYMBOL and self.cur_token_ == symbol: return symbol raise FeatureLibError("Expected '%s'" % symbol, self.cur_token_location_) def expect_keyword_(self, keyword): self.advance_lexer_() if self.cur_token_type_ is Lexer.NAME and self.cur_token_ == keyword: return self.cur_token_ raise FeatureLibError('Expected "%s"' % keyword, self.cur_token_location_) def expect_name_(self): self.advance_lexer_() if self.cur_token_type_ is Lexer.NAME: return self.cur_token_ raise FeatureLibError("Expected a name", self.cur_token_location_) def expect_number_(self): self.advance_lexer_() if self.cur_token_type_ is Lexer.NUMBER: return self.cur_token_ raise FeatureLibError("Expected a number", self.cur_token_location_) def expect_any_number_(self): self.advance_lexer_() if self.cur_token_type_ in Lexer.NUMBERS: return self.cur_token_ raise FeatureLibError( "Expected a decimal, hexadecimal or octal number", self.cur_token_location_ ) def expect_float_(self): self.advance_lexer_() if self.cur_token_type_ is Lexer.FLOAT: return self.cur_token_ raise FeatureLibError( "Expected a floating-point number", self.cur_token_location_ ) def expect_decipoint_(self): if self.next_token_type_ == Lexer.FLOAT: return self.expect_float_() elif self.next_token_type_ is Lexer.NUMBER: return self.expect_number_() / 10 else: raise FeatureLibError( "Expected an integer or floating-point number", self.cur_token_location_ ) def expect_string_(self): self.advance_lexer_() if self.cur_token_type_ is Lexer.STRING: return self.cur_token_ raise FeatureLibError("Expected a string", self.cur_token_location_) def advance_lexer_(self, comments=False): if comments and self.cur_comments_: self.cur_token_type_ = Lexer.COMMENT self.cur_token_, self.cur_token_location_ = self.cur_comments_.pop(0) return else: self.cur_token_type_, self.cur_token_, self.cur_token_location_ = ( self.next_token_type_, self.next_token_, self.next_token_location_, ) while True: try: ( self.next_token_type_, self.next_token_, self.next_token_location_, ) = next(self.lexer_) except StopIteration: self.next_token_type_, self.next_token_ = (None, None) if self.next_token_type_ != Lexer.COMMENT: break self.cur_comments_.append((self.next_token_, self.next_token_location_)) @staticmethod def reverse_string_(s): """'abc' --> 'cba'""" return "".join(reversed(list(s))) def make_cid_range_(self, location, start, limit): """(location, 999, 1001) --> ["cid00999", "cid01000", "cid01001"]""" result = list() if start > limit: raise FeatureLibError( "Bad range: start should be less than limit", location ) for cid in range(start, limit + 1): result.append("cid%05d" % cid) return result def make_glyph_range_(self, location, start, limit): """(location, "a.sc", "d.sc") --> ["a.sc", "b.sc", "c.sc", "d.sc"]""" result = list() if len(start) != len(limit): raise FeatureLibError( 'Bad range: "%s" and "%s" should have the same length' % (start, limit), location, ) rev = self.reverse_string_ prefix = os.path.commonprefix([start, limit]) suffix = rev(os.path.commonprefix([rev(start), rev(limit)])) if len(suffix) > 0: start_range = start[len(prefix) : -len(suffix)] limit_range = limit[len(prefix) : -len(suffix)] else: start_range = start[len(prefix) :] limit_range = limit[len(prefix) :] if start_range >= limit_range: raise FeatureLibError( "Start of range must be smaller than its end", location ) uppercase = re.compile(r"^[A-Z]$") if uppercase.match(start_range) and uppercase.match(limit_range): for c in range(ord(start_range), ord(limit_range) + 1): result.append("%s%c%s" % (prefix, c, suffix)) return result lowercase = re.compile(r"^[a-z]$") if lowercase.match(start_range) and lowercase.match(limit_range): for c in range(ord(start_range), ord(limit_range) + 1): result.append("%s%c%s" % (prefix, c, suffix)) return result digits = re.compile(r"^[0-9]{1,3}$") if digits.match(start_range) and digits.match(limit_range): for i in range(int(start_range, 10), int(limit_range, 10) + 1): number = ("000" + str(i))[-len(start_range) :] result.append("%s%s%s" % (prefix, number, suffix)) return result raise FeatureLibError('Bad range: "%s-%s"' % (start, limit), location)
class SymbolTable(object): def __init__(self): self.scopes_ = [{}] def enter_scope(self): self.scopes_.append({}) def exit_scope(self): self.scopes_.pop() def define(self, name, item): self.scopes_[-1][name] = item def resolve(self, name): for scope in reversed(self.scopes_): item = scope.get(name) if item: return item return None