Source code for fontTools.voltLib.parser

import fontTools.voltLib.ast as ast
from fontTools.voltLib.lexer import Lexer
from fontTools.voltLib.error import VoltLibError
from io import open

PARSE_FUNCS = {
    "DEF_GLYPH": "parse_def_glyph_",
    "DEF_GROUP": "parse_def_group_",
    "DEF_SCRIPT": "parse_def_script_",
    "DEF_LOOKUP": "parse_def_lookup_",
    "DEF_ANCHOR": "parse_def_anchor_",
    "GRID_PPEM": "parse_ppem_",
    "PRESENTATION_PPEM": "parse_ppem_",
    "PPOSITIONING_PPEM": "parse_ppem_",
    "COMPILER_USEEXTENSIONLOOKUPS": "parse_noarg_option_",
    "COMPILER_USEPAIRPOSFORMAT2": "parse_noarg_option_",
    "CMAP_FORMAT": "parse_cmap_format",
    "DO_NOT_TOUCH_CMAP": "parse_noarg_option_",
}


[docs] class Parser(object): def __init__(self, path): self.doc_ = ast.VoltFile() self.glyphs_ = OrderedSymbolTable() self.groups_ = SymbolTable() self.anchors_ = {} # dictionary of SymbolTable() keyed by glyph self.scripts_ = SymbolTable() self.langs_ = SymbolTable() self.lookups_ = SymbolTable() self.next_token_type_, self.next_token_ = (None, None) self.next_token_location_ = None self.make_lexer_(path) self.advance_lexer_()
[docs] def make_lexer_(self, file_or_path): if hasattr(file_or_path, "read"): filename = getattr(file_or_path, "name", None) data = file_or_path.read() else: filename = file_or_path with open(file_or_path, "r") as f: data = f.read() self.lexer_ = Lexer(data, filename)
[docs] def parse(self): statements = self.doc_.statements while self.next_token_type_ is not None: self.advance_lexer_() if self.cur_token_ in PARSE_FUNCS.keys(): func = getattr(self, PARSE_FUNCS[self.cur_token_]) statements.append(func()) elif self.is_cur_keyword_("END"): break else: raise VoltLibError( "Expected " + ", ".join(sorted(PARSE_FUNCS.keys())), self.cur_token_location_, ) return self.doc_
[docs] def parse_def_glyph_(self): assert self.is_cur_keyword_("DEF_GLYPH") location = self.cur_token_location_ name = self.expect_string_() self.expect_keyword_("ID") gid = self.expect_number_() if gid < 0: raise VoltLibError("Invalid glyph ID", self.cur_token_location_) gunicode = None if self.next_token_ == "UNICODE": self.expect_keyword_("UNICODE") gunicode = [self.expect_number_()] if gunicode[0] < 0: raise VoltLibError("Invalid glyph UNICODE", self.cur_token_location_) elif self.next_token_ == "UNICODEVALUES": self.expect_keyword_("UNICODEVALUES") gunicode = self.parse_unicode_values_() gtype = None if self.next_token_ == "TYPE": self.expect_keyword_("TYPE") gtype = self.expect_name_() assert gtype in ("BASE", "LIGATURE", "MARK", "COMPONENT") components = None if self.next_token_ == "COMPONENTS": self.expect_keyword_("COMPONENTS") components = self.expect_number_() self.expect_keyword_("END_GLYPH") if self.glyphs_.resolve(name) is not None: raise VoltLibError( 'Glyph "%s" (gid %i) already defined' % (name, gid), location ) def_glyph = ast.GlyphDefinition( name, gid, gunicode, gtype, components, location=location ) self.glyphs_.define(name, def_glyph) return def_glyph
[docs] def parse_def_group_(self): assert self.is_cur_keyword_("DEF_GROUP") location = self.cur_token_location_ name = self.expect_string_() enum = None if self.next_token_ == "ENUM": enum = self.parse_enum_() self.expect_keyword_("END_GROUP") if self.groups_.resolve(name) is not None: raise VoltLibError( 'Glyph group "%s" already defined, ' "group names are case insensitive" % name, location, ) def_group = ast.GroupDefinition(name, enum, location=location) self.groups_.define(name, def_group) return def_group
[docs] def parse_def_script_(self): assert self.is_cur_keyword_("DEF_SCRIPT") location = self.cur_token_location_ name = None if self.next_token_ == "NAME": self.expect_keyword_("NAME") name = self.expect_string_() self.expect_keyword_("TAG") tag = self.expect_string_() if self.scripts_.resolve(tag) is not None: raise VoltLibError( 'Script "%s" already defined, ' "script tags are case insensitive" % tag, location, ) self.langs_.enter_scope() langs = [] while self.next_token_ != "END_SCRIPT": self.advance_lexer_() lang = self.parse_langsys_() self.expect_keyword_("END_LANGSYS") if self.langs_.resolve(lang.tag) is not None: raise VoltLibError( 'Language "%s" already defined in script "%s", ' "language tags are case insensitive" % (lang.tag, tag), location, ) self.langs_.define(lang.tag, lang) langs.append(lang) self.expect_keyword_("END_SCRIPT") self.langs_.exit_scope() def_script = ast.ScriptDefinition(name, tag, langs, location=location) self.scripts_.define(tag, def_script) return def_script
[docs] def parse_langsys_(self): assert self.is_cur_keyword_("DEF_LANGSYS") location = self.cur_token_location_ name = None if self.next_token_ == "NAME": self.expect_keyword_("NAME") name = self.expect_string_() self.expect_keyword_("TAG") tag = self.expect_string_() features = [] while self.next_token_ != "END_LANGSYS": self.advance_lexer_() feature = self.parse_feature_() self.expect_keyword_("END_FEATURE") features.append(feature) def_langsys = ast.LangSysDefinition(name, tag, features, location=location) return def_langsys
[docs] def parse_feature_(self): assert self.is_cur_keyword_("DEF_FEATURE") location = self.cur_token_location_ self.expect_keyword_("NAME") name = self.expect_string_() self.expect_keyword_("TAG") tag = self.expect_string_() lookups = [] while self.next_token_ != "END_FEATURE": # self.advance_lexer_() self.expect_keyword_("LOOKUP") lookup = self.expect_string_() lookups.append(lookup) feature = ast.FeatureDefinition(name, tag, lookups, location=location) return feature
[docs] def parse_def_lookup_(self): assert self.is_cur_keyword_("DEF_LOOKUP") location = self.cur_token_location_ name = self.expect_string_() if not name[0].isalpha(): raise VoltLibError( 'Lookup name "%s" must start with a letter' % name, location ) if self.lookups_.resolve(name) is not None: raise VoltLibError( 'Lookup "%s" already defined, ' "lookup names are case insensitive" % name, location, ) process_base = True if self.next_token_ == "PROCESS_BASE": self.advance_lexer_() elif self.next_token_ == "SKIP_BASE": self.advance_lexer_() process_base = False process_marks = True mark_glyph_set = None if self.next_token_ == "PROCESS_MARKS": self.advance_lexer_() if self.next_token_ == "MARK_GLYPH_SET": self.advance_lexer_() mark_glyph_set = self.expect_string_() elif self.next_token_ == "ALL": self.advance_lexer_() elif self.next_token_ == "NONE": self.advance_lexer_() process_marks = False elif self.next_token_type_ == Lexer.STRING: process_marks = self.expect_string_() else: raise VoltLibError( "Expected ALL, NONE, MARK_GLYPH_SET or an ID. " "Got %s" % (self.next_token_type_), location, ) elif self.next_token_ == "SKIP_MARKS": self.advance_lexer_() process_marks = False direction = None if self.next_token_ == "DIRECTION": self.expect_keyword_("DIRECTION") direction = self.expect_name_() assert direction in ("LTR", "RTL") reversal = None if self.next_token_ == "REVERSAL": self.expect_keyword_("REVERSAL") reversal = True comments = None if self.next_token_ == "COMMENTS": self.expect_keyword_("COMMENTS") comments = self.expect_string_().replace(r"\n", "\n") context = [] while self.next_token_ in ("EXCEPT_CONTEXT", "IN_CONTEXT"): context = self.parse_context_() as_pos_or_sub = self.expect_name_() sub = None pos = None if as_pos_or_sub == "AS_SUBSTITUTION": sub = self.parse_substitution_(reversal) elif as_pos_or_sub == "AS_POSITION": pos = self.parse_position_() else: raise VoltLibError( "Expected AS_SUBSTITUTION or AS_POSITION. " "Got %s" % (as_pos_or_sub), location, ) def_lookup = ast.LookupDefinition( name, process_base, process_marks, mark_glyph_set, direction, reversal, comments, context, sub, pos, location=location, ) self.lookups_.define(name, def_lookup) return def_lookup
[docs] def parse_context_(self): location = self.cur_token_location_ contexts = [] while self.next_token_ in ("EXCEPT_CONTEXT", "IN_CONTEXT"): side = None coverage = None ex_or_in = self.expect_name_() # side_contexts = [] # XXX if self.next_token_ != "END_CONTEXT": left = [] right = [] while self.next_token_ in ("LEFT", "RIGHT"): side = self.expect_name_() coverage = self.parse_coverage_() if side == "LEFT": left.append(coverage) else: right.append(coverage) self.expect_keyword_("END_CONTEXT") context = ast.ContextDefinition( ex_or_in, left, right, location=location ) contexts.append(context) else: self.expect_keyword_("END_CONTEXT") return contexts
[docs] def parse_substitution_(self, reversal): assert self.is_cur_keyword_("AS_SUBSTITUTION") location = self.cur_token_location_ src = [] dest = [] if self.next_token_ != "SUB": raise VoltLibError("Expected SUB", location) while self.next_token_ == "SUB": self.expect_keyword_("SUB") src.append(self.parse_coverage_()) self.expect_keyword_("WITH") dest.append(self.parse_coverage_()) self.expect_keyword_("END_SUB") self.expect_keyword_("END_SUBSTITUTION") max_src = max([len(cov) for cov in src]) max_dest = max([len(cov) for cov in dest]) # many to many or mixed is invalid if (max_src > 1 and max_dest > 1) or ( reversal and (max_src > 1 or max_dest > 1) ): raise VoltLibError("Invalid substitution type", location) mapping = dict(zip(tuple(src), tuple(dest))) if max_src == 1 and max_dest == 1: if reversal: sub = ast.SubstitutionReverseChainingSingleDefinition( mapping, location=location ) else: sub = ast.SubstitutionSingleDefinition(mapping, location=location) elif max_src == 1 and max_dest > 1: sub = ast.SubstitutionMultipleDefinition(mapping, location=location) elif max_src > 1 and max_dest == 1: sub = ast.SubstitutionLigatureDefinition(mapping, location=location) return sub
[docs] def parse_position_(self): assert self.is_cur_keyword_("AS_POSITION") location = self.cur_token_location_ pos_type = self.expect_name_() if pos_type not in ("ATTACH", "ATTACH_CURSIVE", "ADJUST_PAIR", "ADJUST_SINGLE"): raise VoltLibError( "Expected ATTACH, ATTACH_CURSIVE, ADJUST_PAIR, ADJUST_SINGLE", location ) if pos_type == "ATTACH": position = self.parse_attach_() elif pos_type == "ATTACH_CURSIVE": position = self.parse_attach_cursive_() elif pos_type == "ADJUST_PAIR": position = self.parse_adjust_pair_() elif pos_type == "ADJUST_SINGLE": position = self.parse_adjust_single_() self.expect_keyword_("END_POSITION") return position
[docs] def parse_attach_(self): assert self.is_cur_keyword_("ATTACH") location = self.cur_token_location_ coverage = self.parse_coverage_() coverage_to = [] self.expect_keyword_("TO") while self.next_token_ != "END_ATTACH": cov = self.parse_coverage_() self.expect_keyword_("AT") self.expect_keyword_("ANCHOR") anchor_name = self.expect_string_() coverage_to.append((cov, anchor_name)) self.expect_keyword_("END_ATTACH") position = ast.PositionAttachDefinition( coverage, coverage_to, location=location ) return position
[docs] def parse_attach_cursive_(self): assert self.is_cur_keyword_("ATTACH_CURSIVE") location = self.cur_token_location_ coverages_exit = [] coverages_enter = [] while self.next_token_ != "ENTER": self.expect_keyword_("EXIT") coverages_exit.append(self.parse_coverage_()) while self.next_token_ != "END_ATTACH": self.expect_keyword_("ENTER") coverages_enter.append(self.parse_coverage_()) self.expect_keyword_("END_ATTACH") position = ast.PositionAttachCursiveDefinition( coverages_exit, coverages_enter, location=location ) return position
[docs] def parse_adjust_pair_(self): assert self.is_cur_keyword_("ADJUST_PAIR") location = self.cur_token_location_ coverages_1 = [] coverages_2 = [] adjust_pair = {} while self.next_token_ == "FIRST": self.advance_lexer_() coverage_1 = self.parse_coverage_() coverages_1.append(coverage_1) while self.next_token_ == "SECOND": self.advance_lexer_() coverage_2 = self.parse_coverage_() coverages_2.append(coverage_2) while self.next_token_ != "END_ADJUST": id_1 = self.expect_number_() id_2 = self.expect_number_() self.expect_keyword_("BY") pos_1 = self.parse_pos_() pos_2 = self.parse_pos_() adjust_pair[(id_1, id_2)] = (pos_1, pos_2) self.expect_keyword_("END_ADJUST") position = ast.PositionAdjustPairDefinition( coverages_1, coverages_2, adjust_pair, location=location ) return position
[docs] def parse_adjust_single_(self): assert self.is_cur_keyword_("ADJUST_SINGLE") location = self.cur_token_location_ adjust_single = [] while self.next_token_ != "END_ADJUST": coverages = self.parse_coverage_() self.expect_keyword_("BY") pos = self.parse_pos_() adjust_single.append((coverages, pos)) self.expect_keyword_("END_ADJUST") position = ast.PositionAdjustSingleDefinition(adjust_single, location=location) return position
[docs] def parse_def_anchor_(self): assert self.is_cur_keyword_("DEF_ANCHOR") location = self.cur_token_location_ name = self.expect_string_() self.expect_keyword_("ON") gid = self.expect_number_() self.expect_keyword_("GLYPH") glyph_name = self.expect_name_() self.expect_keyword_("COMPONENT") component = self.expect_number_() # check for duplicate anchor names on this glyph if glyph_name in self.anchors_: anchor = self.anchors_[glyph_name].resolve(name) if anchor is not None and anchor.component == component: raise VoltLibError( 'Anchor "%s" already defined, ' "anchor names are case insensitive" % name, location, ) if self.next_token_ == "LOCKED": locked = True self.advance_lexer_() else: locked = False self.expect_keyword_("AT") pos = self.parse_pos_() self.expect_keyword_("END_ANCHOR") anchor = ast.AnchorDefinition( name, gid, glyph_name, component, locked, pos, location=location ) if glyph_name not in self.anchors_: self.anchors_[glyph_name] = SymbolTable() self.anchors_[glyph_name].define(name, anchor) return anchor
[docs] def parse_adjust_by_(self): self.advance_lexer_() assert self.is_cur_keyword_("ADJUST_BY") adjustment = self.expect_number_() self.expect_keyword_("AT") size = self.expect_number_() return adjustment, size
[docs] def parse_pos_(self): # VOLT syntax doesn't seem to take device Y advance self.advance_lexer_() location = self.cur_token_location_ assert self.is_cur_keyword_("POS"), location adv = None dx = None dy = None adv_adjust_by = {} dx_adjust_by = {} dy_adjust_by = {} if self.next_token_ == "ADV": self.advance_lexer_() adv = self.expect_number_() while self.next_token_ == "ADJUST_BY": adjustment, size = self.parse_adjust_by_() adv_adjust_by[size] = adjustment if self.next_token_ == "DX": self.advance_lexer_() dx = self.expect_number_() while self.next_token_ == "ADJUST_BY": adjustment, size = self.parse_adjust_by_() dx_adjust_by[size] = adjustment if self.next_token_ == "DY": self.advance_lexer_() dy = self.expect_number_() while self.next_token_ == "ADJUST_BY": adjustment, size = self.parse_adjust_by_() dy_adjust_by[size] = adjustment self.expect_keyword_("END_POS") return ast.Pos(adv, dx, dy, adv_adjust_by, dx_adjust_by, dy_adjust_by)
[docs] def parse_unicode_values_(self): location = self.cur_token_location_ try: unicode_values = self.expect_string_().split(",") unicode_values = [int(uni[2:], 16) for uni in unicode_values if uni != ""] except ValueError as err: raise VoltLibError(str(err), location) return unicode_values if unicode_values != [] else None
[docs] def parse_enum_(self): self.expect_keyword_("ENUM") location = self.cur_token_location_ enum = ast.Enum(self.parse_coverage_(), location=location) self.expect_keyword_("END_ENUM") return enum
[docs] def parse_coverage_(self): coverage = [] location = self.cur_token_location_ while self.next_token_ in ("GLYPH", "GROUP", "RANGE", "ENUM"): if self.next_token_ == "ENUM": enum = self.parse_enum_() coverage.append(enum) elif self.next_token_ == "GLYPH": self.expect_keyword_("GLYPH") name = self.expect_string_() coverage.append(ast.GlyphName(name, location=location)) elif self.next_token_ == "GROUP": self.expect_keyword_("GROUP") name = self.expect_string_() coverage.append(ast.GroupName(name, self, location=location)) elif self.next_token_ == "RANGE": self.expect_keyword_("RANGE") start = self.expect_string_() self.expect_keyword_("TO") end = self.expect_string_() coverage.append(ast.Range(start, end, self, location=location)) return tuple(coverage)
[docs] def resolve_group(self, group_name): return self.groups_.resolve(group_name)
[docs] def glyph_range(self, start, end): return self.glyphs_.range(start, end)
[docs] def parse_ppem_(self): location = self.cur_token_location_ ppem_name = self.cur_token_ value = self.expect_number_() setting = ast.SettingDefinition(ppem_name, value, location=location) return setting
[docs] def parse_noarg_option_(self): location = self.cur_token_location_ name = self.cur_token_ value = True setting = ast.SettingDefinition(name, value, location=location) return setting
[docs] def parse_cmap_format(self): location = self.cur_token_location_ name = self.cur_token_ value = (self.expect_number_(), self.expect_number_(), self.expect_number_()) setting = ast.SettingDefinition(name, value, location=location) return setting
[docs] def is_cur_keyword_(self, k): return (self.cur_token_type_ is Lexer.NAME) and (self.cur_token_ == k)
[docs] def expect_string_(self): self.advance_lexer_() if self.cur_token_type_ is not Lexer.STRING: raise VoltLibError("Expected a string", self.cur_token_location_) return self.cur_token_
[docs] 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 VoltLibError('Expected "%s"' % keyword, self.cur_token_location_)
[docs] def expect_name_(self): self.advance_lexer_() if self.cur_token_type_ is Lexer.NAME: return self.cur_token_ raise VoltLibError("Expected a name", self.cur_token_location_)
[docs] def expect_number_(self): self.advance_lexer_() if self.cur_token_type_ is not Lexer.NUMBER: raise VoltLibError("Expected a number", self.cur_token_location_) return self.cur_token_
[docs] def advance_lexer_(self): self.cur_token_type_, self.cur_token_, self.cur_token_location_ = ( self.next_token_type_, self.next_token_, self.next_token_location_, ) try: if self.is_cur_keyword_("END"): raise StopIteration ( self.next_token_type_, self.next_token_, self.next_token_location_, ) = self.lexer_.next() except StopIteration: self.next_token_type_, self.next_token_ = (None, None)
[docs] class SymbolTable(object): def __init__(self): self.scopes_ = [{}]
[docs] def enter_scope(self): self.scopes_.append({})
[docs] def exit_scope(self): self.scopes_.pop()
[docs] def define(self, name, item): self.scopes_[-1][name] = item
[docs] def resolve(self, name, case_insensitive=True): for scope in reversed(self.scopes_): item = scope.get(name) if item: return item if case_insensitive: for key in scope: if key.lower() == name.lower(): return scope[key] return None
[docs] class OrderedSymbolTable(SymbolTable): def __init__(self): self.scopes_ = [{}]
[docs] def enter_scope(self): self.scopes_.append({})
[docs] def resolve(self, name, case_insensitive=False): SymbolTable.resolve(self, name, case_insensitive=case_insensitive)
[docs] def range(self, start, end): for scope in reversed(self.scopes_): if start in scope and end in scope: start_idx = list(scope.keys()).index(start) end_idx = list(scope.keys()).index(end) return list(scope.keys())[start_idx : end_idx + 1] return None