Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2100 insertions, 0 deletions

diff --git a/xpcom/idl-parser/xpidl/xpidl.py b/xpcom/idl-parser/xpidl/xpidl.py
new file mode 100755
index 0000000000..925d588dd5
--- /dev/null
+++ b/xpcom/idl-parser/xpidl/xpidl.py
@@ -0,0 +1,2100 @@
+#!/usr/bin/env python
+# xpidl.py - A parser for cross-platform IDL (XPIDL) files.
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""A parser for cross-platform IDL (XPIDL) files."""
+
+import os.path
+import re
+import sys
+import textwrap
+from collections import namedtuple
+
+import six
+from ply import lex, yacc
+
+"""A type conforms to the following pattern:
+
+    def nativeType(self, calltype):
+        'returns a string representation of the native type
+        calltype must be 'in', 'out', 'inout', or 'element'
+
+Interface members const/method/attribute conform to the following pattern:
+
+    name = 'string'
+
+    def toIDL(self):
+        'returns the member signature as IDL'
+"""
+
+
+# XXX(nika): Fix the IDL files which do this so we can remove this list?
+def rustPreventForward(s):
+    """These types are foward declared as interfaces, but never actually defined
+    in IDL files. We don't want to generate references to them in rust for that
+    reason."""
+    return s in (
+        "nsIFrame",
+        "nsSubDocumentFrame",
+    )
+
+
+def attlistToIDL(attlist):
+    if len(attlist) == 0:
+        return ""
+
+    attlist = list(attlist)
+    attlist.sort(key=lambda a: a[0])
+
+    return "[%s] " % ",".join(
+        [
+            "%s%s" % (name, value is not None and "(%s)" % value or "")
+            for name, value, aloc in attlist
+        ]
+    )
+
+
+_paramsHardcode = {
+    2: ("array", "shared", "iid_is", "size_is", "retval"),
+    3: ("array", "size_is", "const"),
+}
+
+
+def paramAttlistToIDL(attlist):
+    if len(attlist) == 0:
+        return ""
+
+    # Hack alert: g_hash_table_foreach is pretty much unimitatable... hardcode
+    # quirk
+    attlist = list(attlist)
+    sorted = []
+    if len(attlist) in _paramsHardcode:
+        for p in _paramsHardcode[len(attlist)]:
+            i = 0
+            while i < len(attlist):
+                if attlist[i][0] == p:
+                    sorted.append(attlist[i])
+                    del attlist[i]
+                    continue
+
+                i += 1
+
+    sorted.extend(attlist)
+
+    return "[%s] " % ", ".join(
+        [
+            "%s%s" % (name, value is not None and " (%s)" % value or "")
+            for name, value, aloc in sorted
+        ]
+    )
+
+
+def unaliasType(t):
+    while t.kind == "typedef":
+        t = t.realtype
+    assert t is not None
+    return t
+
+
+def getBuiltinOrNativeTypeName(t):
+    t = unaliasType(t)
+    if t.kind == "builtin":
+        return t.name
+    elif t.kind == "native":
+        assert t.specialtype is not None
+        return "[%s]" % t.specialtype
+    else:
+        return None
+
+
+class BuiltinLocation(object):
+    def get(self):
+        return "<builtin type>"
+
+    def __str__(self):
+        return self.get()
+
+
+class Builtin(object):
+    kind = "builtin"
+    location = BuiltinLocation
+
+    def __init__(self, name, nativename, rustname, signed=False, maybeConst=False):
+        self.name = name
+        self.nativename = nativename
+        self.rustname = rustname
+        self.signed = signed
+        self.maybeConst = maybeConst
+
+    def isPointer(self):
+        """Check if this type is a pointer type - this will control how pointers act"""
+        return self.nativename.endswith("*")
+
+    def nativeType(self, calltype, shared=False, const=False):
+        if self.name in ["string", "wstring"] and calltype == "element":
+            raise IDLError(
+                "Use string class types for string Array elements", self.location
+            )
+
+        if const:
+            print(
+                IDLError(
+                    "[const] doesn't make sense on builtin types.",
+                    self.location,
+                    warning=True,
+                ),
+                file=sys.stderr,
+            )
+            const = "const "
+        elif calltype == "in" and self.isPointer():
+            const = "const "
+        elif shared:
+            if not self.isPointer():
+                raise IDLError(
+                    "[shared] not applicable to non-pointer types.", self.location
+                )
+            const = "const "
+        else:
+            const = ""
+        return "%s%s %s" % (const, self.nativename, "*" if "out" in calltype else "")
+
+    def rustType(self, calltype, shared=False, const=False):
+        # We want to rewrite any *mut pointers to *const pointers if constness
+        # was requested.
+        const = const or ("out" not in calltype and self.isPointer()) or shared
+        rustname = self.rustname
+        if const and self.isPointer():
+            rustname = self.rustname.replace("*mut", "*const")
+
+        return "%s%s" % ("*mut " if "out" in calltype else "", rustname)
+
+
+builtinNames = [
+    Builtin("boolean", "bool", "bool"),
+    Builtin("void", "void", "libc::c_void"),
+    Builtin("octet", "uint8_t", "u8", False, True),
+    Builtin("short", "int16_t", "i16", True, True),
+    Builtin("long", "int32_t", "i32", True, True),
+    Builtin("long long", "int64_t", "i64", True, True),
+    Builtin("unsigned short", "uint16_t", "u16", False, True),
+    Builtin("unsigned long", "uint32_t", "u32", False, True),
+    Builtin("unsigned long long", "uint64_t", "u64", False, True),
+    Builtin("float", "float", "libc::c_float", True, False),
+    Builtin("double", "double", "libc::c_double", True, False),
+    Builtin("char", "char", "libc::c_char", True, False),
+    Builtin("string", "char *", "*const libc::c_char", False, False),
+    Builtin("wchar", "char16_t", "u16", False, False),
+    Builtin("wstring", "char16_t *", "*const u16", False, False),
+    # As seen in mfbt/RefCountType.h, this type has special handling to
+    # maintain binary compatibility with MSCOM's IUnknown that cannot be
+    # expressed in XPIDL.
+    Builtin(
+        "MozExternalRefCountType", "MozExternalRefCountType", "MozExternalRefCountType"
+    ),
+]
+
+builtinMap = {}
+for b in builtinNames:
+    builtinMap[b.name] = b
+
+
+class Location(object):
+    _line = None
+
+    def __init__(self, lexer, lineno, lexpos):
+        self._lineno = lineno
+        self._lexpos = lexpos
+        self._lexdata = lexer.lexdata
+        self._file = getattr(lexer, "filename", "<unknown>")
+
+    def __eq__(self, other):
+        return self._lexpos == other._lexpos and self._file == other._file
+
+    def resolve(self):
+        if self._line:
+            return
+
+        startofline = self._lexdata.rfind("\n", 0, self._lexpos) + 1
+        endofline = self._lexdata.find("\n", self._lexpos, self._lexpos + 80)
+        self._line = self._lexdata[startofline:endofline]
+        self._colno = self._lexpos - startofline
+
+    def pointerline(self):
+        def i():
+            for i in range(0, self._colno):
+                yield " "
+            yield "^"
+
+        return "".join(i())
+
+    def get(self):
+        self.resolve()
+        return "%s line %s:%s" % (self._file, self._lineno, self._colno)
+
+    def __str__(self):
+        self.resolve()
+        return "%s line %s:%s\n%s\n%s" % (
+            self._file,
+            self._lineno,
+            self._colno,
+            self._line,
+            self.pointerline(),
+        )
+
+
+class NameMap(object):
+    """Map of name -> object. Each object must have a .name and .location property.
+    Setting the same name twice throws an error."""
+
+    def __init__(self):
+        self._d = {}
+
+    def __getitem__(self, key):
+        if key in builtinMap:
+            return builtinMap[key]
+        return self._d[key]
+
+    def __iter__(self):
+        return six.itervalues(self._d)
+
+    def __contains__(self, key):
+        return key in builtinMap or key in self._d
+
+    def set(self, object):
+        if object.name in builtinMap:
+            raise IDLError(
+                "name '%s' is a builtin and cannot be redeclared" % (object.name),
+                object.location,
+            )
+        if object.name.startswith("_"):
+            object.name = object.name[1:]
+        if object.name in self._d:
+            old = self._d[object.name]
+            if old == object:
+                return
+            if isinstance(old, Forward) and isinstance(object, Interface):
+                self._d[object.name] = object
+            elif isinstance(old, Interface) and isinstance(object, Forward):
+                pass
+            else:
+                raise IDLError(
+                    "name '%s' specified twice. Previous location: %s"
+                    % (object.name, self._d[object.name].location),
+                    object.location,
+                )
+        else:
+            self._d[object.name] = object
+
+    def get(self, id, location):
+        try:
+            return self[id]
+        except KeyError:
+            raise IDLError(f"Name '{id}' not found", location)
+
+
+class RustNoncompat(Exception):
+    """
+    This exception is raised when a particular type or function cannot be safely exposed to
+    rust code
+    """
+
+    def __init__(self, reason):
+        self.reason = reason
+
+    def __str__(self):
+        return self.reason
+
+
+class IDLError(Exception):
+    def __init__(self, message, location, warning=False, notes=None):
+        self.message = message
+        self.location = location
+        self.warning = warning
+        self.notes = notes
+
+    def __str__(self):
+        error = "%s: %s, %s" % (
+            self.warning and "warning" or "error",
+            self.message,
+            self.location,
+        )
+        if self.notes is not None:
+            error += "\nnote: %s" % self.notes
+        return error
+
+
+class Include(object):
+    kind = "include"
+
+    def __init__(self, filename, location):
+        self.filename = filename
+        self.location = location
+
+    def __str__(self):
+        return "".join(["include '%s'\n" % self.filename])
+
+    def resolve(self, parent):
+        def incfiles():
+            yield self.filename
+            for dir in parent.incdirs:
+                yield os.path.join(dir, self.filename)
+
+        for file in incfiles():
+            if not os.path.exists(file):
+                continue
+
+            if file in parent.includeCache:
+                self.IDL = parent.includeCache[file]
+            else:
+                self.IDL = parent.parser.parse(
+                    open(file, encoding="utf-8").read(), filename=file
+                )
+                self.IDL.resolve(
+                    parent.incdirs,
+                    parent.parser,
+                    parent.webidlconfig,
+                    parent.includeCache,
+                )
+                parent.includeCache[file] = self.IDL
+
+            for type in self.IDL.getNames():
+                parent.setName(type)
+            parent.deps.extend(self.IDL.deps)
+            return
+
+        raise IDLError("File '%s' not found" % self.filename, self.location)
+
+
+class IDL(object):
+    def __init__(self, productions):
+        self.hasSequence = False
+        self.productions = productions
+        self.deps = []
+
+    def setName(self, object):
+        self.namemap.set(object)
+
+    def getName(self, id, location):
+        if id.name == "Array":
+            if id.params is None or len(id.params) != 1:
+                raise IDLError("Array takes exactly 1 parameter", location)
+            self.hasSequence = True
+            return Array(self.getName(id.params[0], location), location)
+
+        if id.params is not None:
+            raise IDLError("Generic type '%s' unrecognized" % id.name, location)
+
+        try:
+            return self.namemap[id.name]
+        except KeyError:
+            raise IDLError("type '%s' not found" % id.name, location)
+
+    def hasName(self, id):
+        return id in self.namemap
+
+    def getNames(self):
+        return iter(self.namemap)
+
+    def __str__(self):
+        return "".join([str(p) for p in self.productions])
+
+    def resolve(self, incdirs, parser, webidlconfig, includeCache=None):
+        self.namemap = NameMap()
+        self.incdirs = incdirs
+        self.parser = parser
+        self.webidlconfig = webidlconfig
+        self.includeCache = {} if includeCache is None else includeCache
+        for p in self.productions:
+            p.resolve(self)
+
+    def includes(self):
+        for p in self.productions:
+            if p.kind == "include":
+                yield p
+        if self.hasSequence:
+            yield Include("nsTArray.h", BuiltinLocation)
+
+    def needsJSTypes(self):
+        for p in self.productions:
+            if p.kind == "interface" and p.needsJSTypes():
+                return True
+        return False
+
+
+class CDATA(object):
+    kind = "cdata"
+    _re = re.compile(r"\n+")
+
+    def __init__(self, data, location):
+        self.data = self._re.sub("\n", data)
+        self.location = location
+
+    def resolve(self, parent):
+        # This can be a false-positive if the word `virtual` is included in a
+        # comment, however this doesn't seem to happen very often.
+        if isinstance(parent, Interface) and re.search(r"\bvirtual\b", self.data):
+            raise IDLError(
+                "cannot declare a C++ `virtual` member in XPIDL interface",
+                self.location,
+                notes=textwrap.fill(
+                    """All virtual members must be declared directly using XPIDL.
+                    Both the Rust bindings and XPConnect rely on the per-platform
+                    vtable layouts generated by the XPIDL compiler to allow
+                    cross-language XPCOM method calls between JS and C++.
+                    Consider using a `[notxpcom, nostdcall]` method instead."""
+                ),
+            )
+
+    def __str__(self):
+        return "cdata: %s\n\t%r\n" % (self.location.get(), self.data)
+
+    def count(self):
+        return 0
+
+
+class Typedef(object):
+    kind = "typedef"
+
+    def __init__(self, type, name, location, doccomments):
+        self.type = type
+        self.name = name
+        self.location = location
+        self.doccomments = doccomments
+
+    def __eq__(self, other):
+        return self.name == other.name and self.type == other.type
+
+    def resolve(self, parent):
+        parent.setName(self)
+        self.realtype = parent.getName(self.type, self.location)
+
+        if not isinstance(self.realtype, (Builtin, CEnum, Native, Typedef)):
+            raise IDLError("Unsupported typedef target type", self.location)
+
+    def nativeType(self, calltype):
+        return "%s %s" % (self.name, "*" if "out" in calltype else "")
+
+    def rustType(self, calltype):
+        if self.name == "nsresult":
+            return "%s::nserror::nsresult" % ("*mut " if "out" in calltype else "")
+
+        return "%s%s" % ("*mut " if "out" in calltype else "", self.name)
+
+    def __str__(self):
+        return "typedef %s %s\n" % (self.type, self.name)
+
+
+class Forward(object):
+    kind = "forward"
+
+    def __init__(self, name, location, doccomments):
+        self.name = name
+        self.location = location
+        self.doccomments = doccomments
+
+    def __eq__(self, other):
+        return other.kind == "forward" and other.name == self.name
+
+    def resolve(self, parent):
+        # Hack alert: if an identifier is already present, move the doccomments
+        # forward.
+        if parent.hasName(self.name):
+            for i in range(0, len(parent.productions)):
+                if parent.productions[i] is self:
+                    break
+            for i in range(i + 1, len(parent.productions)):
+                if hasattr(parent.productions[i], "doccomments"):
+                    parent.productions[i].doccomments[0:0] = self.doccomments
+                    break
+
+        parent.setName(self)
+
+    def nativeType(self, calltype):
+        if calltype == "element":
+            return "RefPtr<%s>" % self.name
+        return "%s *%s" % (self.name, "*" if "out" in calltype else "")
+
+    def rustType(self, calltype):
+        if rustPreventForward(self.name):
+            raise RustNoncompat("forward declaration %s is unsupported" % self.name)
+        if calltype == "element":
+            return "Option<RefPtr<%s>>" % self.name
+        return "%s*const %s" % ("*mut" if "out" in calltype else "", self.name)
+
+    def __str__(self):
+        return "forward-declared %s\n" % self.name
+
+
+class Native(object):
+    kind = "native"
+
+    modifier = None
+    specialtype = None
+
+    # A tuple type here means that a custom value is used for each calltype:
+    #   (in, out/inout, array element) respectively.
+    # A `None` here means that the written type should be used as-is.
+    specialtypes = {
+        "nsid": None,
+        "utf8string": ("const nsACString&", "nsACString&", "nsCString"),
+        "cstring": ("const nsACString&", "nsACString&", "nsCString"),
+        "astring": ("const nsAString&", "nsAString&", "nsString"),
+        "jsval": ("JS::Handle<JS::Value>", "JS::MutableHandle<JS::Value>", "JS::Value"),
+        "promise": "::mozilla::dom::Promise",
+    }
+
+    def __init__(self, name, nativename, attlist, location):
+        self.name = name
+        self.nativename = nativename
+        self.location = location
+
+        for name, value, aloc in attlist:
+            if value is not None:
+                raise IDLError("Unexpected attribute value", aloc)
+            if name in ("ptr", "ref"):
+                if self.modifier is not None:
+                    raise IDLError("More than one ptr/ref modifier", aloc)
+                self.modifier = name
+            elif name in self.specialtypes.keys():
+                if self.specialtype is not None:
+                    raise IDLError("More than one special type", aloc)
+                self.specialtype = name
+                if self.specialtypes[name] is not None:
+                    self.nativename = self.specialtypes[name]
+            else:
+                raise IDLError("Unexpected attribute", aloc)
+
+    def __eq__(self, other):
+        return (
+            self.name == other.name
+            and self.nativename == other.nativename
+            and self.modifier == other.modifier
+            and self.specialtype == other.specialtype
+        )
+
+    def resolve(self, parent):
+        parent.setName(self)
+
+    def isPtr(self, calltype):
+        return self.modifier == "ptr"
+
+    def isRef(self, calltype):
+        return self.modifier == "ref"
+
+    def nativeType(self, calltype, const=False, shared=False):
+        if shared:
+            if calltype != "out":
+                raise IDLError(
+                    "[shared] only applies to out parameters.", self.location
+                )
+            const = True
+
+        if isinstance(self.nativename, tuple):
+            if calltype == "in":
+                return self.nativename[0] + " "
+            elif "out" in calltype:
+                return self.nativename[1] + " "
+            else:
+                return self.nativename[2] + " "
+
+        # 'in' nsid parameters should be made 'const'
+        if self.specialtype == "nsid" and calltype == "in":
+            const = True
+
+        if calltype == "element":
+            if self.specialtype == "nsid":
+                if self.isPtr(calltype):
+                    raise IDLError(
+                        "Array<nsIDPtr> not yet supported. "
+                        "File an XPConnect bug if you need it.",
+                        self.location,
+                    )
+
+                # ns[CI]?IDs should be held directly in Array<T>s
+                return self.nativename
+
+            if self.isRef(calltype):
+                raise IDLError(
+                    "[ref] qualified type unsupported in Array<T>", self.location
+                )
+
+            # Promises should be held in RefPtr<T> in Array<T>s
+            if self.specialtype == "promise":
+                return "RefPtr<mozilla::dom::Promise>"
+
+        if self.isRef(calltype):
+            m = "& "  # [ref] is always passed with a single indirection
+        else:
+            m = "* " if "out" in calltype else ""
+            if self.isPtr(calltype):
+                m += "* "
+        return "%s%s %s" % (const and "const " or "", self.nativename, m)
+
+    def rustType(self, calltype, const=False, shared=False):
+        # For the most part, 'native' types don't make sense in rust, as they
+        # are native C++ types. However, we can support a few types here, as
+        # they're important and can easily be translated.
+        #
+        # NOTE: This code doesn't try to perfectly match C++ constness, as
+        # constness doesn't affect ABI, and raw pointers are already unsafe.
+
+        if self.modifier not in ["ptr", "ref"]:
+            raise RustNoncompat("Rust only supports [ref] / [ptr] native types")
+
+        if shared:
+            if calltype != "out":
+                raise IDLError(
+                    "[shared] only applies to out parameters.", self.location
+                )
+            const = True
+
+        # 'in' nsid parameters should be made 'const'
+        if self.specialtype == "nsid" and calltype == "in":
+            const = True
+
+        prefix = "*const " if const or shared else "*mut "
+        if "out" in calltype and self.isPtr(calltype):
+            prefix = "*mut " + prefix
+
+        if self.specialtype:
+            # The string types are very special, and need to be handled seperately.
+            if self.specialtype in ["cstring", "utf8string"]:
+                if calltype == "in":
+                    return "*const ::nsstring::nsACString"
+                elif "out" in calltype:
+                    return "*mut ::nsstring::nsACString"
+                else:
+                    return "::nsstring::nsCString"
+            if self.specialtype == "astring":
+                if calltype == "in":
+                    return "*const ::nsstring::nsAString"
+                elif "out" in calltype:
+                    return "*mut ::nsstring::nsAString"
+                else:
+                    return "::nsstring::nsString"
+            # nsid has some special handling, but generally re-uses the generic
+            # prefix handling above.
+            if self.specialtype == "nsid":
+                if "element" in calltype:
+                    if self.isPtr(calltype):
+                        raise IDLError(
+                            "Array<nsIDPtr> not yet supported. "
+                            "File an XPConnect bug if you need it.",
+                            self.location,
+                        )
+                    return self.nativename
+                return prefix + self.nativename
+            raise RustNoncompat("special type %s unsupported" % self.specialtype)
+
+        # These 3 special types correspond to native pointer types which can
+        # generally be supported behind pointers. Other types are not supported
+        # for now.
+        if self.nativename == "void":
+            return prefix + "libc::c_void"
+        if self.nativename == "char":
+            return prefix + "libc::c_char"
+        if self.nativename == "char16_t":
+            return prefix + "u16"
+
+        raise RustNoncompat("native type %s unsupported" % self.nativename)
+
+    def __str__(self):
+        return "native %s(%s)\n" % (self.name, self.nativename)
+
+
+class WebIDL(object):
+    kind = "webidl"
+
+    def __init__(self, name, location):
+        self.name = name
+        self.location = location
+
+    def __eq__(self, other):
+        return other.kind == "webidl" and self.name == other.name
+
+    def resolve(self, parent):
+        # XXX(nika): We don't handle _every_ kind of webidl object here (as that
+        # would be hard). For example, we don't support nsIDOM*-defaulting
+        # interfaces.
+        # TODO: More explicit compile-time checks?
+
+        assert (
+            parent.webidlconfig is not None
+        ), "WebIDL declarations require passing webidlconfig to resolve."
+
+        # Resolve our native name according to the WebIDL configs.
+        config = parent.webidlconfig.get(self.name, {})
+        self.native = config.get("nativeType")
+        if self.native is None:
+            self.native = "mozilla::dom::%s" % self.name
+        self.headerFile = config.get("headerFile")
+        if self.headerFile is None:
+            self.headerFile = self.native.replace("::", "/") + ".h"
+
+        parent.setName(self)
+
+    def nativeType(self, calltype, const=False):
+        if calltype == "element":
+            return "RefPtr<%s%s>" % ("const " if const else "", self.native)
+        return "%s%s *%s" % (
+            "const " if const else "",
+            self.native,
+            "*" if "out" in calltype else "",
+        )
+
+    def rustType(self, calltype, const=False):
+        # Just expose the type as a void* - we can't do any better.
+        return "%s*const libc::c_void" % ("*mut " if "out" in calltype else "")
+
+    def __str__(self):
+        return "webidl %s\n" % self.name
+
+
+class Interface(object):
+    kind = "interface"
+
+    def __init__(self, name, attlist, base, members, location, doccomments):
+        self.name = name
+        self.attributes = InterfaceAttributes(attlist, location)
+        self.base = base
+        self.members = members
+        self.location = location
+        self.namemap = NameMap()
+        self.doccomments = doccomments
+        self.nativename = name
+
+        for m in members:
+            if not isinstance(m, CDATA):
+                self.namemap.set(m)
+
+    def __eq__(self, other):
+        return self.name == other.name and self.location == other.location
+
+    def resolve(self, parent):
+        self.idl = parent
+
+        if not self.attributes.scriptable and self.attributes.builtinclass:
+            raise IDLError(
+                "Non-scriptable interface '%s' doesn't need to be marked builtinclass"
+                % self.name,
+                self.location,
+            )
+
+        # Hack alert: if an identifier is already present, libIDL assigns
+        # doc comments incorrectly. This is quirks-mode extraordinaire!
+        if parent.hasName(self.name):
+            for member in self.members:
+                if hasattr(member, "doccomments"):
+                    member.doccomments[0:0] = self.doccomments
+                    break
+            self.doccomments = parent.getName(TypeId(self.name), None).doccomments
+
+        if self.attributes.function:
+            has_method = False
+            for member in self.members:
+                if member.kind == "method":
+                    if has_method:
+                        raise IDLError(
+                            "interface '%s' has multiple methods, but marked 'function'"
+                            % self.name,
+                            self.location,
+                        )
+                    else:
+                        has_method = True
+
+        parent.setName(self)
+        if self.base is not None:
+            realbase = parent.getName(TypeId(self.base), self.location)
+            if realbase.kind != "interface":
+                raise IDLError(
+                    "interface '%s' inherits from non-interface type '%s'"
+                    % (self.name, self.base),
+                    self.location,
+                )
+
+            if self.attributes.scriptable and not realbase.attributes.scriptable:
+                raise IDLError(
+                    "interface '%s' is scriptable but derives from "
+                    "non-scriptable '%s'" % (self.name, self.base),
+                    self.location,
+                    warning=True,
+                )
+
+            if (
+                self.attributes.scriptable
+                and realbase.attributes.builtinclass
+                and not self.attributes.builtinclass
+            ):
+                raise IDLError(
+                    "interface '%s' is not builtinclass but derives from "
+                    "builtinclass '%s'" % (self.name, self.base),
+                    self.location,
+                )
+        elif self.name != "nsISupports":
+            raise IDLError(
+                "Interface '%s' must inherit from nsISupports" % self.name,
+                self.location,
+            )
+
+        for member in self.members:
+            member.resolve(self)
+
+        # The number 250 is NOT arbitrary; this number is the maximum number of
+        # stub entries defined in xpcom/reflect/xptcall/genstubs.pl
+        # Do not increase this value without increasing the number in that
+        # location, or you WILL cause otherwise unknown problems!
+        if self.countEntries() > 250 and not self.attributes.builtinclass:
+            raise IDLError(
+                "interface '%s' has too many entries" % self.name, self.location
+            )
+
+    def nativeType(self, calltype, const=False):
+        if calltype == "element":
+            return "RefPtr<%s>" % self.name
+        return "%s%s *%s" % (
+            "const " if const else "",
+            self.name,
+            "*" if "out" in calltype else "",
+        )
+
+    def rustType(self, calltype, const=False):
+        if calltype == "element":
+            return "Option<RefPtr<%s>>" % self.name
+        return "%s*const %s" % ("*mut " if "out" in calltype else "", self.name)
+
+    def __str__(self):
+        l = ["interface %s\n" % self.name]
+        if self.base is not None:
+            l.append("\tbase %s\n" % self.base)
+        l.append(str(self.attributes))
+        if self.members is None:
+            l.append("\tincomplete type\n")
+        else:
+            for m in self.members:
+                l.append(str(m))
+        return "".join(l)
+
+    def getConst(self, name, location):
+        # The constant may be in a base class
+        iface = self
+        while name not in iface.namemap and iface.base is not None:
+            iface = self.idl.getName(TypeId(iface.base), self.location)
+        if name not in iface.namemap:
+            raise IDLError("cannot find symbol '%s'" % name, location)
+        c = iface.namemap.get(name, location)
+        if c.kind != "const":
+            raise IDLError("symbol '%s' is not a constant" % name, location)
+
+        return c.getValue()
+
+    def needsJSTypes(self):
+        for m in self.members:
+            if m.kind == "attribute" and m.type == TypeId("jsval"):
+                return True
+            if m.kind == "method" and m.needsJSTypes():
+                return True
+        return False
+
+    def countEntries(self):
+        """Returns the number of entries in the vtable for this interface."""
+        total = sum(member.count() for member in self.members)
+        if self.base is not None:
+            realbase = self.idl.getName(TypeId(self.base), self.location)
+            total += realbase.countEntries()
+        return total
+
+
+class InterfaceAttributes(object):
+    uuid = None
+    scriptable = False
+    builtinclass = False
+    function = False
+    main_process_scriptable_only = False
+
+    def setuuid(self, value):
+        self.uuid = value.lower()
+
+    def setscriptable(self):
+        self.scriptable = True
+
+    def setfunction(self):
+        self.function = True
+
+    def setbuiltinclass(self):
+        self.builtinclass = True
+
+    def setmain_process_scriptable_only(self):
+        self.main_process_scriptable_only = True
+
+    actions = {
+        "uuid": (True, setuuid),
+        "scriptable": (False, setscriptable),
+        "builtinclass": (False, setbuiltinclass),
+        "function": (False, setfunction),
+        "object": (False, lambda self: True),
+        "main_process_scriptable_only": (False, setmain_process_scriptable_only),
+    }
+
+    def __init__(self, attlist, location):
+        def badattribute(self):
+            raise IDLError("Unexpected interface attribute '%s'" % name, location)
+
+        for name, val, aloc in attlist:
+            hasval, action = self.actions.get(name, (False, badattribute))
+            if hasval:
+                if val is None:
+                    raise IDLError("Expected value for attribute '%s'" % name, aloc)
+
+                action(self, val)
+            else:
+                if val is not None:
+                    raise IDLError("Unexpected value for attribute '%s'" % name, aloc)
+
+                action(self)
+
+        if self.uuid is None:
+            raise IDLError("interface has no uuid", location)
+
+    def __str__(self):
+        l = []
+        if self.uuid:
+            l.append("\tuuid: %s\n" % self.uuid)
+        if self.scriptable:
+            l.append("\tscriptable\n")
+        if self.builtinclass:
+            l.append("\tbuiltinclass\n")
+        if self.function:
+            l.append("\tfunction\n")
+        if self.main_process_scriptable_only:
+            l.append("\tmain_process_scriptable_only\n")
+        return "".join(l)
+
+
+class ConstMember(object):
+    kind = "const"
+
+    def __init__(self, type, name, value, location, doccomments):
+        self.type = type
+        self.name = name
+        self.valueFn = value
+        self.location = location
+        self.doccomments = doccomments
+
+    def resolve(self, parent):
+        self.realtype = parent.idl.getName(self.type, self.location)
+        self.iface = parent
+        basetype = self.realtype
+        while isinstance(basetype, Typedef):
+            basetype = basetype.realtype
+        if not isinstance(basetype, Builtin) or not basetype.maybeConst:
+            raise IDLError(
+                "const may only be a short or long type, not %s" % self.type,
+                self.location,
+            )
+
+        self.basetype = basetype
+        # Value is a lambda. Resolve it.
+        self.value = self.valueFn(self.iface)
+
+        min_val = -(2 ** 31) if basetype.signed else 0
+        max_val = 2 ** 31 - 1 if basetype.signed else 2 ** 32 - 1
+        if self.value < min_val or self.value > max_val:
+            raise IDLError(
+                "xpidl constants must fit within %s"
+                % ("int32_t" if basetype.signed else "uint32_t"),
+                self.location,
+            )
+
+    def getValue(self):
+        return self.value
+
+    def __str__(self):
+        return "\tconst %s %s = %s\n" % (self.type, self.name, self.getValue())
+
+    def count(self):
+        return 0
+
+
+# Represents a single name/value pair in a CEnum
+class CEnumVariant(object):
+    # Treat CEnumVariants as consts in terms of value resolution, so we can
+    # do things like binary operation values for enum members.
+    kind = "const"
+
+    def __init__(self, name, value, location):
+        self.name = name
+        self.valueFn = value
+        self.location = location
+
+    def getValue(self):
+        return self.value
+
+
+class CEnum(object):
+    kind = "cenum"
+
+    def __init__(self, width, name, variants, location, doccomments):
+        # We have to set a name here, otherwise we won't pass namemap checks on
+        # the interface. This name will change it in resolve(), in order to
+        # namespace the enum within the interface.
+        self.name = name
+        self.basename = name
+        self.width = width
+        self.location = location
+        self.namemap = NameMap()
+        self.doccomments = doccomments
+        self.variants = variants
+        if self.width not in (8, 16, 32):
+            raise IDLError("Width must be one of {8, 16, 32}", self.location)
+
+    def resolve(self, iface):
+        self.iface = iface
+        # Renaming enum to faux-namespace the enum type to the interface in JS
+        # so we don't collide in the global namespace. Hacky/ugly but it does
+        # the job well enough, and the name will still be interface::variant in
+        # C++.
+        self.name = "%s_%s" % (self.iface.name, self.basename)
+        self.iface.idl.setName(self)
+
+        # Compute the value for each enum variant that doesn't set its own
+        # value
+        next_value = 0
+        for variant in self.variants:
+            # CEnum variants resolve to interface level consts in javascript,
+            # meaning their names could collide with other interface members.
+            # Iterate through all CEnum variants to make sure there are no
+            # collisions.
+            self.iface.namemap.set(variant)
+            # Value may be a lambda. If it is, resolve it.
+            if variant.valueFn:
+                next_value = variant.value = variant.valueFn(self.iface)
+            else:
+                variant.value = next_value
+            next_value += 1
+
+    def count(self):
+        return 0
+
+    def nativeType(self, calltype):
+        if "out" in calltype:
+            return "%s::%s *" % (self.iface.name, self.basename)
+        return "%s::%s " % (self.iface.name, self.basename)
+
+    def rustType(self, calltype):
+        return "%s u%d" % ("*mut" if "out" in calltype else "", self.width)
+
+    def __str__(self):
+        body = ", ".join("%s = %s" % v for v in self.variants)
+        return "\tcenum %s : %d { %s };\n" % (self.name, self.width, body)
+
+
+# Infallible doesn't work for all return types.
+#
+# It also must be implemented on a builtinclass (otherwise it'd be unsound as
+# it could be implemented by JS).
+def ensureInfallibleIsSound(methodOrAttribute):
+    if not methodOrAttribute.infallible:
+        return
+    if methodOrAttribute.realtype.kind not in [
+        "builtin",
+        "interface",
+        "forward",
+        "webidl",
+        "cenum",
+    ]:
+        raise IDLError(
+            "[infallible] only works on interfaces, domobjects, and builtin types "
+            "(numbers, booleans, cenum, and raw char types)",
+            methodOrAttribute.location,
+        )
+    ifaceAttributes = methodOrAttribute.iface.attributes
+    if ifaceAttributes.scriptable and not ifaceAttributes.builtinclass:
+        raise IDLError(
+            "[infallible] attributes and methods are only allowed on "
+            "non-[scriptable] or [builtinclass] interfaces",
+            methodOrAttribute.location,
+        )
+
+    if methodOrAttribute.notxpcom:
+        raise IDLError(
+            "[infallible] does not make sense for a [notxpcom] " "method or attribute",
+            methodOrAttribute.location,
+        )
+
+
+# An interface cannot be implemented by JS if it has a notxpcom or nostdcall
+# method or attribute, so it must be marked as builtinclass.
+def ensureBuiltinClassIfNeeded(methodOrAttribute):
+    iface = methodOrAttribute.iface
+    if not iface.attributes.scriptable or iface.attributes.builtinclass:
+        return
+    if iface.name == "nsISupports":
+        return
+    if methodOrAttribute.notxpcom:
+        raise IDLError(
+            (
+                "scriptable interface '%s' must be marked [builtinclass] because it "
+                "contains a [notxpcom] %s '%s'"
+            )
+            % (iface.name, methodOrAttribute.kind, methodOrAttribute.name),
+            methodOrAttribute.location,
+        )
+    if methodOrAttribute.nostdcall:
+        raise IDLError(
+            (
+                "scriptable interface '%s' must be marked [builtinclass] because it "
+                "contains a [nostdcall] %s '%s'"
+            )
+            % (iface.name, methodOrAttribute.kind, methodOrAttribute.name),
+            methodOrAttribute.location,
+        )
+
+
+class Attribute(object):
+    kind = "attribute"
+    noscript = False
+    notxpcom = False
+    readonly = False
+    symbol = False
+    implicit_jscontext = False
+    nostdcall = False
+    must_use = False
+    binaryname = None
+    infallible = False
+    # explicit_setter_can_run_script is true if the attribute is explicitly
+    # annotated as having a setter that can cause script to run.
+    explicit_setter_can_run_script = False
+    # explicit_getter_can_run_script is true if the attribute is explicitly
+    # annotated as having a getter that can cause script to run.
+    explicit_getter_can_run_script = False
+
+    def __init__(self, type, name, attlist, readonly, location, doccomments):
+        self.type = type
+        self.name = name
+        self.attlist = attlist
+        self.readonly = readonly
+        self.location = location
+        self.doccomments = doccomments
+
+        for name, value, aloc in attlist:
+            if name == "binaryname":
+                if value is None:
+                    raise IDLError("binaryname attribute requires a value", aloc)
+
+                self.binaryname = value
+                continue
+
+            if value is not None:
+                raise IDLError("Unexpected attribute value", aloc)
+
+            if name == "noscript":
+                self.noscript = True
+            elif name == "notxpcom":
+                self.notxpcom = True
+            elif name == "symbol":
+                self.symbol = True
+            elif name == "implicit_jscontext":
+                self.implicit_jscontext = True
+            elif name == "nostdcall":
+                self.nostdcall = True
+            elif name == "must_use":
+                self.must_use = True
+            elif name == "infallible":
+                self.infallible = True
+            elif name == "can_run_script":
+                if (
+                    self.explicit_setter_can_run_script
+                    or self.explicit_getter_can_run_script
+                ):
+                    raise IDLError(
+                        "Redundant getter_can_run_script or "
+                        "setter_can_run_script annotation on "
+                        "attribute",
+                        aloc,
+                    )
+                self.explicit_setter_can_run_script = True
+                self.explicit_getter_can_run_script = True
+            elif name == "setter_can_run_script":
+                if self.explicit_setter_can_run_script:
+                    raise IDLError(
+                        "Redundant setter_can_run_script annotation " "on attribute",
+                        aloc,
+                    )
+                self.explicit_setter_can_run_script = True
+            elif name == "getter_can_run_script":
+                if self.explicit_getter_can_run_script:
+                    raise IDLError(
+                        "Redundant getter_can_run_script annotation " "on attribute",
+                        aloc,
+                    )
+                self.explicit_getter_can_run_script = True
+            else:
+                raise IDLError("Unexpected attribute '%s'" % name, aloc)
+
+    def resolve(self, iface):
+        self.iface = iface
+        self.realtype = iface.idl.getName(self.type, self.location)
+
+        ensureInfallibleIsSound(self)
+        ensureBuiltinClassIfNeeded(self)
+
+    def toIDL(self):
+        attribs = attlistToIDL(self.attlist)
+        readonly = self.readonly and "readonly " or ""
+        return "%s%sattribute %s %s;" % (attribs, readonly, self.type, self.name)
+
+    def isScriptable(self):
+        if not self.iface.attributes.scriptable:
+            return False
+        return not (self.noscript or self.notxpcom or self.nostdcall)
+
+    def __str__(self):
+        return "\t%sattribute %s %s\n" % (
+            self.readonly and "readonly " or "",
+            self.type,
+            self.name,
+        )
+
+    def count(self):
+        return self.readonly and 1 or 2
+
+
+class Method(object):
+    kind = "method"
+    noscript = False
+    notxpcom = False
+    symbol = False
+    binaryname = None
+    implicit_jscontext = False
+    nostdcall = False
+    must_use = False
+    optional_argc = False
+    # explicit_can_run_script is true if the method is explicitly annotated
+    # as being able to cause script to run.
+    explicit_can_run_script = False
+    infallible = False
+
+    def __init__(self, type, name, attlist, paramlist, location, doccomments, raises):
+        self.type = type
+        self.name = name
+        self.attlist = attlist
+        self.params = paramlist
+        self.location = location
+        self.doccomments = doccomments
+        self.raises = raises
+
+        for name, value, aloc in attlist:
+            if name == "binaryname":
+                if value is None:
+                    raise IDLError("binaryname attribute requires a value", aloc)
+
+                self.binaryname = value
+                continue
+
+            if value is not None:
+                raise IDLError("Unexpected attribute value", aloc)
+
+            if name == "noscript":
+                self.noscript = True
+            elif name == "notxpcom":
+                self.notxpcom = True
+            elif name == "symbol":
+                self.symbol = True
+            elif name == "implicit_jscontext":
+                self.implicit_jscontext = True
+            elif name == "optional_argc":
+                self.optional_argc = True
+            elif name == "nostdcall":
+                self.nostdcall = True
+            elif name == "must_use":
+                self.must_use = True
+            elif name == "can_run_script":
+                self.explicit_can_run_script = True
+            elif name == "infallible":
+                self.infallible = True
+            else:
+                raise IDLError("Unexpected attribute '%s'" % name, aloc)
+
+        self.namemap = NameMap()
+        for p in paramlist:
+            self.namemap.set(p)
+
+    def resolve(self, iface):
+        self.iface = iface
+        self.realtype = self.iface.idl.getName(self.type, self.location)
+
+        ensureInfallibleIsSound(self)
+        ensureBuiltinClassIfNeeded(self)
+
+        for p in self.params:
+            p.resolve(self)
+        for p in self.params:
+            if p.retval and p != self.params[-1]:
+                raise IDLError(
+                    "'retval' parameter '%s' is not the last parameter" % p.name,
+                    self.location,
+                )
+            if p.size_is:
+                size_param = self.namemap.get(p.size_is, p.location)
+                if (
+                    p.paramtype.count("in") == 1
+                    and size_param.paramtype.count("in") == 0
+                ):
+                    raise IDLError(
+                        "size_is parameter of an input must also be an input",
+                        p.location,
+                    )
+                if getBuiltinOrNativeTypeName(size_param.realtype) != "unsigned long":
+                    raise IDLError(
+                        "size_is parameter must have type 'unsigned long'",
+                        p.location,
+                    )
+            if p.iid_is:
+                iid_param = self.namemap.get(p.iid_is, p.location)
+                if (
+                    p.paramtype.count("in") == 1
+                    and iid_param.paramtype.count("in") == 0
+                ):
+                    raise IDLError(
+                        "iid_is parameter of an input must also be an input",
+                        p.location,
+                    )
+                if getBuiltinOrNativeTypeName(iid_param.realtype) != "[nsid]":
+                    raise IDLError(
+                        "iid_is parameter must be an nsIID",
+                        self.location,
+                    )
+
+    def isScriptable(self):
+        if not self.iface.attributes.scriptable:
+            return False
+        return not (self.noscript or self.notxpcom or self.nostdcall)
+
+    def __str__(self):
+        return "\t%s %s(%s)\n" % (
+            self.type,
+            self.name,
+            ", ".join([p.name for p in self.params]),
+        )
+
+    def toIDL(self):
+        if len(self.raises):
+            raises = " raises (%s)" % ",".join(self.raises)
+        else:
+            raises = ""
+
+        return "%s%s %s (%s)%s;" % (
+            attlistToIDL(self.attlist),
+            self.type,
+            self.name,
+            ", ".join([p.toIDL() for p in self.params]),
+            raises,
+        )
+
+    def needsJSTypes(self):
+        if self.implicit_jscontext:
+            return True
+        if self.type == TypeId("jsval"):
+            return True
+        for p in self.params:
+            t = p.realtype
+            if isinstance(t, Native) and t.specialtype == "jsval":
+                return True
+        return False
+
+    def count(self):
+        return 1
+
+
+class Param(object):
+    size_is = None
+    iid_is = None
+    const = False
+    array = False
+    retval = False
+    shared = False
+    optional = False
+    default_value = None
+
+    def __init__(self, paramtype, type, name, attlist, location, realtype=None):
+        self.paramtype = paramtype
+        self.type = type
+        self.name = name
+        self.attlist = attlist
+        self.location = location
+        self.realtype = realtype
+
+        for name, value, aloc in attlist:
+            # Put the value-taking attributes first!
+            if name == "size_is":
+                if value is None:
+                    raise IDLError("'size_is' must specify a parameter", aloc)
+                self.size_is = value
+            elif name == "iid_is":
+                if value is None:
+                    raise IDLError("'iid_is' must specify a parameter", aloc)
+                self.iid_is = value
+            elif name == "default":
+                if value is None:
+                    raise IDLError("'default' must specify a default value", aloc)
+                self.default_value = value
+            else:
+                if value is not None:
+                    raise IDLError("Unexpected value for attribute '%s'" % name, aloc)
+
+                if name == "const":
+                    self.const = True
+                elif name == "array":
+                    self.array = True
+                elif name == "retval":
+                    self.retval = True
+                elif name == "shared":
+                    self.shared = True
+                elif name == "optional":
+                    self.optional = True
+                else:
+                    raise IDLError("Unexpected attribute '%s'" % name, aloc)
+
+    def resolve(self, method):
+        self.realtype = method.iface.idl.getName(self.type, self.location)
+        if self.array:
+            self.realtype = LegacyArray(self.realtype)
+
+    def nativeType(self):
+        kwargs = {}
+        if self.shared:
+            kwargs["shared"] = True
+        if self.const:
+            kwargs["const"] = True
+
+        try:
+            return self.realtype.nativeType(self.paramtype, **kwargs)
+        except IDLError as e:
+            raise IDLError(str(e), self.location)
+        except TypeError:
+            raise IDLError("Unexpected parameter attribute", self.location)
+
+    def rustType(self):
+        kwargs = {}
+        if self.shared:
+            kwargs["shared"] = True
+        if self.const:
+            kwargs["const"] = True
+
+        try:
+            return self.realtype.rustType(self.paramtype, **kwargs)
+        except IDLError as e:
+            raise IDLError(str(e), self.location)
+        except TypeError:
+            raise IDLError("Unexpected parameter attribute", self.location)
+
+    def toIDL(self):
+        return "%s%s %s %s" % (
+            paramAttlistToIDL(self.attlist),
+            self.paramtype,
+            self.type,
+            self.name,
+        )
+
+
+class LegacyArray(object):
+    def __init__(self, basetype):
+        self.type = basetype
+        self.location = self.type.location
+
+    def nativeType(self, calltype, const=False):
+        if "element" in calltype:
+            raise IDLError("nested [array] unsupported", self.location)
+
+        # For legacy reasons, we have to add a 'const ' to builtin pointer array
+        # types. (`[array] in string` and `[array] in wstring` parameters)
+        if (
+            calltype == "in"
+            and isinstance(self.type, Builtin)
+            and self.type.isPointer()
+        ):
+            const = True
+
+        return "%s%s*%s" % (
+            "const " if const else "",
+            self.type.nativeType("legacyelement"),
+            "*" if "out" in calltype else "",
+        )
+
+    def rustType(self, calltype, const=False):
+        return "%s%s%s" % (
+            "*mut " if "out" in calltype else "",
+            "*const " if const else "*mut ",
+            self.type.rustType("legacyelement"),
+        )
+
+
+class Array(object):
+    kind = "array"
+
+    def __init__(self, type, location):
+        self.type = type
+        self.location = location
+
+    @property
+    def name(self):
+        return "Array<%s>" % self.type.name
+
+    def resolve(self, idl):
+        idl.getName(self.type, self.location)
+
+    def nativeType(self, calltype):
+        if calltype == "legacyelement":
+            raise IDLError("[array] Array<T> is unsupported", self.location)
+
+        base = "nsTArray<%s>" % self.type.nativeType("element")
+        if "out" in calltype:
+            return "%s& " % base
+        elif "in" == calltype:
+            return "const %s& " % base
+        else:
+            return base
+
+    def rustType(self, calltype):
+        if calltype == "legacyelement":
+            raise IDLError("[array] Array<T> is unsupported", self.location)
+
+        base = "thin_vec::ThinVec<%s>" % self.type.rustType("element")
+        if "out" in calltype:
+            return "*mut %s" % base
+        elif "in" == calltype:
+            return "*const %s" % base
+        else:
+            return base
+
+
+TypeId = namedtuple("TypeId", "name params")
+
+
+# Make str(TypeId) produce a nicer value
+TypeId.__str__ = (
+    lambda self: "%s<%s>" % (self.name, ", ".join(str(p) for p in self.params))
+    if self.params is not None
+    else self.name
+)
+
+
+# Allow skipping 'params' in TypeId(..)
+TypeId.__new__.__defaults__ = (None,)
+
+
+class IDLParser(object):
+    keywords = {
+        "cenum": "CENUM",
+        "const": "CONST",
+        "interface": "INTERFACE",
+        "in": "IN",
+        "inout": "INOUT",
+        "out": "OUT",
+        "attribute": "ATTRIBUTE",
+        "raises": "RAISES",
+        "readonly": "READONLY",
+        "native": "NATIVE",
+        "typedef": "TYPEDEF",
+        "webidl": "WEBIDL",
+    }
+
+    tokens = [
+        "IDENTIFIER",
+        "CDATA",
+        "INCLUDE",
+        "IID",
+        "NUMBER",
+        "HEXNUM",
+        "LSHIFT",
+        "RSHIFT",
+        "NATIVEID",
+    ]
+
+    tokens.extend(keywords.values())
+
+    states = (("nativeid", "exclusive"),)
+
+    hexchar = r"[a-fA-F0-9]"
+
+    t_NUMBER = r"-?\d+"
+    t_HEXNUM = r"0x%s+" % hexchar
+    t_LSHIFT = r"<<"
+    t_RSHIFT = r">>"
+
+    literals = '"(){}[]<>,;:=|+-*'
+
+    t_ignore = " \t"
+
+    def t_multilinecomment(self, t):
+        r"/\*(\n|.)*?\*/"
+        t.lexer.lineno += t.value.count("\n")
+        if t.value.startswith("/**"):
+            self._doccomments.append(t.value)
+
+    def t_singlelinecomment(self, t):
+        r"//[^\n]*"
+
+    def t_IID(self, t):
+        return t
+
+    t_IID.__doc__ = r"%(c)s{8}-%(c)s{4}-%(c)s{4}-%(c)s{4}-%(c)s{12}" % {"c": hexchar}
+
+    def t_IDENTIFIER(self, t):
+        r"(unsigned\ long\ long|unsigned\ short|unsigned\ long|long\ long)(?!_?[A-Za-z][A-Za-z_0-9])|_?[A-Za-z][A-Za-z_0-9]*"  # NOQA: E501
+        t.type = self.keywords.get(t.value, "IDENTIFIER")
+        return t
+
+    def t_LCDATA(self, t):
+        r"%\{[ ]*C\+\+[ ]*\n(?P<cdata>(\n|.)*?\n?)%\}[ ]*(C\+\+)?"
+        t.type = "CDATA"
+        t.value = t.lexer.lexmatch.group("cdata")
+        t.lexer.lineno += t.value.count("\n")
+        return t
+
+    def t_INCLUDE(self, t):
+        r'\#include[ \t]+"[^"\n]+"'
+        inc, value, end = t.value.split('"')
+        t.value = value
+        return t
+
+    def t_directive(self, t):
+        r"\#(?P<directive>[a-zA-Z]+)[^\n]+"
+        raise IDLError(
+            "Unrecognized directive %s" % t.lexer.lexmatch.group("directive"),
+            Location(
+                lexer=self.lexer, lineno=self.lexer.lineno, lexpos=self.lexer.lexpos
+            ),
+        )
+
+    def t_newline(self, t):
+        r"\n+"
+        t.lexer.lineno += len(t.value)
+
+    def t_nativeid_NATIVEID(self, t):
+        # Matches non-parenthesis characters, or a single open and closing
+        # parenthesis with at least one non-parenthesis character before,
+        # between and after them (for compatibility with std::function).
+        r"[^()\n]+(?:\([^()\n]+\)[^()\n]+)?(?=\))"
+        t.lexer.begin("INITIAL")
+        return t
+
+    t_nativeid_ignore = ""
+
+    def t_ANY_error(self, t):
+        raise IDLError(
+            "unrecognized input",
+            Location(
+                lexer=self.lexer, lineno=self.lexer.lineno, lexpos=self.lexer.lexpos
+            ),
+        )
+
+    precedence = (
+        ("left", "|"),
+        ("left", "LSHIFT", "RSHIFT"),
+        ("left", "+", "-"),
+        ("left", "*"),
+        ("left", "UMINUS"),
+    )
+
+    def p_idlfile(self, p):
+        """idlfile : productions"""
+        p[0] = IDL(p[1])
+
+    def p_productions_start(self, p):
+        """productions :"""
+        p[0] = []
+
+    def p_productions_cdata(self, p):
+        """productions : CDATA productions"""
+        p[0] = list(p[2])
+        p[0].insert(0, CDATA(p[1], self.getLocation(p, 1)))
+
+    def p_productions_include(self, p):
+        """productions : INCLUDE productions"""
+        p[0] = list(p[2])
+        p[0].insert(0, Include(p[1], self.getLocation(p, 1)))
+
+    def p_productions_interface(self, p):
+        """productions : interface productions
+        | typedef productions
+        | native productions
+        | webidl productions"""
+        p[0] = list(p[2])
+        p[0].insert(0, p[1])
+
+    def p_typedef(self, p):
+        """typedef : TYPEDEF type IDENTIFIER ';'"""
+        p[0] = Typedef(
+            type=p[2],
+            name=p[3],
+            location=self.getLocation(p, 1),
+            doccomments=p.slice[1].doccomments,
+        )
+
+    def p_native(self, p):
+        """native : attributes NATIVE IDENTIFIER afternativeid '(' NATIVEID ')' ';'"""
+        p[0] = Native(
+            name=p[3],
+            nativename=p[6],
+            attlist=p[1]["attlist"],
+            location=self.getLocation(p, 2),
+        )
+
+    def p_afternativeid(self, p):
+        """afternativeid :"""
+        # this is a place marker: we switch the lexer into literal identifier
+        # mode here, to slurp up everything until the closeparen
+        self.lexer.begin("nativeid")
+
+    def p_webidl(self, p):
+        """webidl : WEBIDL IDENTIFIER ';'"""
+        p[0] = WebIDL(name=p[2], location=self.getLocation(p, 2))
+
+    def p_anyident(self, p):
+        """anyident : IDENTIFIER
+        | CONST"""
+        p[0] = {"value": p[1], "location": self.getLocation(p, 1)}
+
+    def p_attributes(self, p):
+        """attributes : '[' attlist ']'
+        |"""
+        if len(p) == 1:
+            p[0] = {"attlist": []}
+        else:
+            p[0] = {"attlist": p[2], "doccomments": p.slice[1].doccomments}
+
+    def p_attlist_start(self, p):
+        """attlist : attribute"""
+        p[0] = [p[1]]
+
+    def p_attlist_continue(self, p):
+        """attlist : attribute ',' attlist"""
+        p[0] = list(p[3])
+        p[0].insert(0, p[1])
+
+    def p_attribute(self, p):
+        """attribute : anyident attributeval"""
+        p[0] = (p[1]["value"], p[2], p[1]["location"])
+
+    def p_attributeval(self, p):
+        """attributeval : '(' IDENTIFIER ')'
+        | '(' IID ')'
+        |"""
+        if len(p) > 1:
+            p[0] = p[2]
+
+    def p_interface(self, p):
+        """interface : attributes INTERFACE IDENTIFIER ifacebase ifacebody ';'"""
+        atts, INTERFACE, name, base, body, SEMI = p[1:]
+        attlist = atts["attlist"]
+        doccomments = []
+        if "doccomments" in atts:
+            doccomments.extend(atts["doccomments"])
+        doccomments.extend(p.slice[2].doccomments)
+
+        def loc():
+            return self.getLocation(p, 2)
+
+        if body is None:
+            # forward-declared interface... must not have attributes!
+            if len(attlist) != 0:
+                raise IDLError(
+                    "Forward-declared interface must not have attributes", loc()
+                )
+
+            if base is not None:
+                raise IDLError("Forward-declared interface must not have a base", loc())
+            p[0] = Forward(name=name, location=loc(), doccomments=doccomments)
+        else:
+            p[0] = Interface(
+                name=name,
+                attlist=attlist,
+                base=base,
+                members=body,
+                location=loc(),
+                doccomments=doccomments,
+            )
+
+    def p_ifacebody(self, p):
+        """ifacebody : '{' members '}'
+        |"""
+        if len(p) > 1:
+            p[0] = p[2]
+
+    def p_ifacebase(self, p):
+        """ifacebase : ':' IDENTIFIER
+        |"""
+        if len(p) == 3:
+            p[0] = p[2]
+
+    def p_members_start(self, p):
+        """members :"""
+        p[0] = []
+
+    def p_members_continue(self, p):
+        """members : member members"""
+        p[0] = list(p[2])
+        p[0].insert(0, p[1])
+
+    def p_member_cdata(self, p):
+        """member : CDATA"""
+        p[0] = CDATA(p[1], self.getLocation(p, 1))
+
+    def p_member_const(self, p):
+        """member : CONST type IDENTIFIER '=' number ';'"""
+        p[0] = ConstMember(
+            type=p[2],
+            name=p[3],
+            value=p[5],
+            location=self.getLocation(p, 1),
+            doccomments=p.slice[1].doccomments,
+        )
+
+    # All "number" products return a function(interface)
+
+    def p_number_decimal(self, p):
+        """number : NUMBER"""
+        n = int(p[1])
+        p[0] = lambda i: n
+
+    def p_number_hex(self, p):
+        """number : HEXNUM"""
+        n = int(p[1], 16)
+        p[0] = lambda i: n
+
+    def p_number_identifier(self, p):
+        """number : IDENTIFIER"""
+        id = p[1]
+        loc = self.getLocation(p, 1)
+        p[0] = lambda i: i.getConst(id, loc)
+
+    def p_number_paren(self, p):
+        """number : '(' number ')'"""
+        p[0] = p[2]
+
+    def p_number_neg(self, p):
+        """number : '-' number %prec UMINUS"""
+        n = p[2]
+        p[0] = lambda i: -n(i)
+
+    def p_number_add(self, p):
+        """number : number '+' number
+        | number '-' number
+        | number '*' number"""
+        n1 = p[1]
+        n2 = p[3]
+        if p[2] == "+":
+            p[0] = lambda i: n1(i) + n2(i)
+        elif p[2] == "-":
+            p[0] = lambda i: n1(i) - n2(i)
+        else:
+            p[0] = lambda i: n1(i) * n2(i)
+
+    def p_number_shift(self, p):
+        """number : number LSHIFT number
+        | number RSHIFT number"""
+        n1 = p[1]
+        n2 = p[3]
+        if p[2] == "<<":
+            p[0] = lambda i: n1(i) << n2(i)
+        else:
+            p[0] = lambda i: n1(i) >> n2(i)
+
+    def p_number_bitor(self, p):
+        """number : number '|' number"""
+        n1 = p[1]
+        n2 = p[3]
+        p[0] = lambda i: n1(i) | n2(i)
+
+    def p_member_cenum(self, p):
+        """member : CENUM IDENTIFIER ':' NUMBER '{' variants '}' ';'"""
+        p[0] = CEnum(
+            name=p[2],
+            width=int(p[4]),
+            variants=p[6],
+            location=self.getLocation(p, 1),
+            doccomments=p.slice[1].doccomments,
+        )
+
+    def p_variants_start(self, p):
+        """variants :"""
+        p[0] = []
+
+    def p_variants_single(self, p):
+        """variants : variant"""
+        p[0] = [p[1]]
+
+    def p_variants_continue(self, p):
+        """variants : variant ',' variants"""
+        p[0] = [p[1]] + p[3]
+
+    def p_variant_implicit(self, p):
+        """variant : IDENTIFIER"""
+        p[0] = CEnumVariant(p[1], None, self.getLocation(p, 1))
+
+    def p_variant_explicit(self, p):
+        """variant : IDENTIFIER '=' number"""
+        p[0] = CEnumVariant(p[1], p[3], self.getLocation(p, 1))
+
+    def p_member_att(self, p):
+        """member : attributes optreadonly ATTRIBUTE type IDENTIFIER ';'"""
+        if "doccomments" in p[1]:
+            doccomments = p[1]["doccomments"]
+        elif p[2] is not None:
+            doccomments = p[2]
+        else:
+            doccomments = p.slice[3].doccomments
+
+        p[0] = Attribute(
+            type=p[4],
+            name=p[5],
+            attlist=p[1]["attlist"],
+            readonly=p[2] is not None,
+            location=self.getLocation(p, 3),
+            doccomments=doccomments,
+        )
+
+    def p_member_method(self, p):
+        """member : attributes type IDENTIFIER '(' paramlist ')' raises ';'"""
+        if "doccomments" in p[1]:
+            doccomments = p[1]["doccomments"]
+        else:
+            doccomments = p.slice[2].doccomments
+
+        p[0] = Method(
+            type=p[2],
+            name=p[3],
+            attlist=p[1]["attlist"],
+            paramlist=p[5],
+            location=self.getLocation(p, 3),
+            doccomments=doccomments,
+            raises=p[7],
+        )
+
+    def p_paramlist(self, p):
+        """paramlist : param moreparams
+        |"""
+        if len(p) == 1:
+            p[0] = []
+        else:
+            p[0] = list(p[2])
+            p[0].insert(0, p[1])
+
+    def p_moreparams_start(self, p):
+        """moreparams :"""
+        p[0] = []
+
+    def p_moreparams_continue(self, p):
+        """moreparams : ',' param moreparams"""
+        p[0] = list(p[3])
+        p[0].insert(0, p[2])
+
+    def p_param(self, p):
+        """param : attributes paramtype type IDENTIFIER"""
+        p[0] = Param(
+            paramtype=p[2],
+            type=p[3],
+            name=p[4],
+            attlist=p[1]["attlist"],
+            location=self.getLocation(p, 4),
+        )
+
+    def p_paramtype(self, p):
+        """paramtype : IN
+        | INOUT
+        | OUT"""
+        p[0] = p[1]
+
+    def p_optreadonly(self, p):
+        """optreadonly : READONLY
+        |"""
+        if len(p) > 1:
+            p[0] = p.slice[1].doccomments
+        else:
+            p[0] = None
+
+    def p_raises(self, p):
+        """raises : RAISES '(' idlist ')'
+        |"""
+        if len(p) == 1:
+            p[0] = []
+        else:
+            p[0] = p[3]
+
+    def p_idlist(self, p):
+        """idlist : IDENTIFIER"""
+        p[0] = [p[1]]
+
+    def p_idlist_continue(self, p):
+        """idlist : IDENTIFIER ',' idlist"""
+        p[0] = list(p[3])
+        p[0].insert(0, p[1])
+
+    def p_type_id(self, p):
+        """type : IDENTIFIER"""
+        p[0] = TypeId(name=p[1])
+        p.slice[0].doccomments = p.slice[1].doccomments
+
+    def p_type_generic(self, p):
+        """type : IDENTIFIER '<' typelist '>'"""
+        p[0] = TypeId(name=p[1], params=p[3])
+        p.slice[0].doccomments = p.slice[1].doccomments
+
+    def p_typelist(self, p):
+        """typelist : type"""
+        p[0] = [p[1]]
+
+    def p_typelist_continue(self, p):
+        """typelist : type ',' typelist"""
+        p[0] = list(p[3])
+        p[0].insert(0, p[1])
+
+    def p_error(self, t):
+        if not t:
+            raise IDLError(
+                "Syntax Error at end of file. Possibly due to missing semicolon(;), braces(}) "
+                "or both",
+                None,
+            )
+        else:
+            location = Location(self.lexer, t.lineno, t.lexpos)
+            raise IDLError("invalid syntax", location)
+
+    def __init__(self):
+        self._doccomments = []
+        self.lexer = lex.lex(object=self, debug=False)
+        self.parser = yacc.yacc(module=self, write_tables=False, debug=False)
+
+    def clearComments(self):
+        self._doccomments = []
+
+    def token(self):
+        t = self.lexer.token()
+        if t is not None and t.type != "CDATA":
+            t.doccomments = self._doccomments
+            self._doccomments = []
+        return t
+
+    def parse(self, data, filename=None):
+        if filename is not None:
+            self.lexer.filename = filename
+        self.lexer.lineno = 1
+        self.lexer.input(data)
+        idl = self.parser.parse(lexer=self)
+        if filename is not None:
+            idl.deps.append(filename)
+        return idl
+
+    def getLocation(self, p, i):
+        return Location(self.lexer, p.lineno(i), p.lexpos(i))
+
+
+if __name__ == "__main__":
+    p = IDLParser()
+    for f in sys.argv[1:]:
+        print("Parsing %s" % f)
+        p.parse(open(f, encoding="utf-8").read(), filename=f)