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//! Break a string into a set of directory-object Items.
//!
//! This module defines Item, which represents a basic entry in a
//! directory document, and NetDocReader, which is used to break a
//! string into Items.
use crate::parse::keyword::Keyword;
use crate::types::misc::FromBytes;
use crate::util::PauseAt;
use crate::{Error, ParseErrorKind as EK, Pos, Result};
use std::cell::{Ref, RefCell};
use std::str::FromStr;
use tor_error::internal;
/// Return true iff a given character is "space" according to the rules
/// of dir-spec.txt
pub(crate) fn is_sp(c: char) -> bool {
c == ' ' || c == '\t'
}
/// Check that all the characters in `s` are valid base64.
///
/// This is not a perfect check for base64ness -- it is mainly meant
/// to help us recover after unterminated base64.
fn b64check(s: &str) -> Result<()> {
for b in s.bytes() {
match b {
b'=' => (),
b'a'..=b'z' => (),
b'A'..=b'Z' => (),
b'0'..=b'9' => (),
b'/' | b'+' => (),
_ => {
return Err(EK::BadObjectBase64.at_pos(Pos::at(s)));
};
Ok(())
/// A tagged object that is part of a directory Item.
/// This represents a single blob within a pair of "-----BEGIN
/// FOO-----" and "-----END FOO-----". The data is not guaranteed to
/// be actual base64 when this object is created: doing so would
/// require either that we parse the base64 twice, or that we allocate
/// a buffer to hold the data before it's needed.
#[derive(Clone, Copy, Debug)]
pub(crate) struct Object<'a> {
/// Reference to the "tag" string (the 'foo') in the BEGIN line.
tag: &'a str,
/// Reference to the allegedly base64-encoded data. This may or
/// may not actually be base64 at this point.
data: &'a str,
/// Reference to the END line for this object. This doesn't
/// need to be parsed, but it's used to find where this object
/// ends.
endline: &'a str,
/// A single part of a directory object.
/// Each Item -- called an "entry" in dir-spec.txt -- has a keyword, a
/// (possibly empty) set of arguments, and an optional object.
/// This is a zero-copy implementation that points to slices within a
/// containing string.
#[derive(Clone, Debug)]
pub(crate) struct Item<'a, K: Keyword> {
/// The keyword that determines the type of this item.
kwd: K,
/// A reference to the actual string that defines the keyword for
/// this item.
kwd_str: &'a str,
/// Reference to the arguments that appear in the same line after the
/// keyword. Does not include the terminating newline or the
/// space that separates the keyword for its arguments.
args: &'a str,
/// The arguments, split by whitespace. This vector is constructed
/// as needed, using interior mutability.
split_args: RefCell<Option<Vec<&'a str>>>,
/// If present, a base-64-encoded object that appeared at the end
/// of this item.
object: Option<Object<'a>>,
/// A cursor into a string that returns Items one by one.
/// (This type isn't used directly, but is returned wrapped in a Peekable.)
#[derive(Debug)]
struct NetDocReaderBase<'a, K: Keyword> {
/// The string we're parsing.
s: &'a str,
/// Our position within the string.
off: usize,
/// Tells Rust it's okay that we are parameterizing on K.
_k: std::marker::PhantomData<K>,
impl<'a, K: Keyword> NetDocReaderBase<'a, K> {
/// Create a new NetDocReader to split a string into tokens.
fn new(s: &'a str) -> Self {
NetDocReaderBase {
s,
off: 0,
_k: std::marker::PhantomData,
/// Return the current Pos within the string.
fn pos(&self, pos: usize) -> Pos {
Pos::from_offset(self.s, pos)
/// Skip forward by n bytes.
/// (Note that standard caveats with byte-oriented processing of
/// UTF-8 strings apply.)
fn advance(&mut self, n: usize) -> Result<()> {
if n > self.remaining() {
return Err(
Error::from(internal!("tried to advance past end of document"))
.at_pos(Pos::from_offset(self.s, self.off)),
);
self.off += n;
/// Return the remaining number of bytes in this reader.
fn remaining(&self) -> usize {
self.s.len() - self.off
/// Return true if the next characters in this reader are `s`
fn starts_with(&self, s: &str) -> bool {
self.s[self.off..].starts_with(s)
/// Try to extract a NL-terminated line from this reader. Always
/// remove data if the reader is nonempty.
fn line(&mut self) -> Result<&'a str> {
let remainder = &self.s[self.off..];
if let Some(nl_pos) = remainder.find('\n') {
self.advance(nl_pos + 1)?;
let line = &remainder[..nl_pos];
// TODO: we should probably detect \r and do something about it.
// Just ignoring it isn't the right answer, though.
Ok(line)
} else {
self.advance(remainder.len())?; // drain everything.
Err(EK::TruncatedLine.at_pos(self.pos(self.s.len())))
/// Try to extract a line that begins with a keyword from this reader.
/// Returns a (kwd, args) tuple on success.
fn kwdline(&mut self) -> Result<(&'a str, &'a str)> {
let pos = self.off;
let line = self.line()?;
let (line, anno_ok) = if let Some(rem) = line.strip_prefix("opt ") {
(rem, false)
(line, true)
let mut parts_iter = line.splitn(2, |c| c == ' ' || c == '\t');
let kwd = match parts_iter.next() {
Some(k) => k,
// This case seems like it can't happen: split always returns
// something, apparently.
None => return Err(EK::MissingKeyword.at_pos(self.pos(pos))),
if !keyword_ok(kwd, anno_ok) {
return Err(EK::BadKeyword.at_pos(self.pos(pos)));
// TODO(nickm): dir-spec does not yet allow unicode in the arguments, but we're
// assuming that proposal 285 is accepted.
let args = match parts_iter.next() {
Some(a) => a,
// take a zero-length slice, so it will be within the string.
None => &kwd[kwd.len()..],
Ok((kwd, args))
/// Try to extract an Object beginning wrapped within BEGIN/END tags.
/// Returns Ok(Some(Object(...))) on success if an object is
/// found, Ok(None) if no object is found, and Err only if a
/// corrupt object is found.
fn object(&mut self) -> Result<Option<Object<'a>>> {
/// indicates the start of an object
const BEGIN_STR: &str = "-----BEGIN ";
/// indicates the end of an object
const END_STR: &str = "-----END ";
/// indicates the end of a begin or end tag.
const TAG_END: &str = "-----";
if !self.starts_with(BEGIN_STR) {
return Ok(None);
if !line.ends_with(TAG_END) {
return Err(EK::BadObjectBeginTag.at_pos(self.pos(pos)));
let tag = &line[BEGIN_STR.len()..(line.len() - TAG_END.len())];
if !tag_keyword_ok(tag) {
let datapos = self.off;
let (endlinepos, endline) = loop {
let p = self.off;
if line.starts_with(END_STR) {
break (p, line);
// Exit if this line isn't plausible base64. Otherwise,
// an unterminated base64 block could potentially
// "consume" all the rest of the string, which would stop
// us from recovering.
b64check(line).map_err(|e| e.within(self.s))?;
let data = &self.s[datapos..endlinepos];
if !endline.ends_with(TAG_END) {
return Err(EK::BadObjectEndTag.at_pos(self.pos(endlinepos)));
let endtag = &endline[END_STR.len()..(endline.len() - TAG_END.len())];
if endtag != tag {
return Err(EK::BadObjectMismatchedTag.at_pos(self.pos(endlinepos)));
Ok(Some(Object { tag, data, endline }))
/// Read the next Item from this NetDocReaderBase.
/// If successful, returns Ok(Some(Item)), or Ok(None) if exhausted.
/// Returns Err on failure.
/// Always consumes at least one line if possible; always ends on a
/// line boundary if one exists.
fn item(&mut self) -> Result<Option<Item<'a, K>>> {
if self.remaining() == 0 {
let (kwd_str, args) = self.kwdline()?;
let object = self.object()?;
let split_args = RefCell::new(None);
let kwd = K::from_str(kwd_str);
Ok(Some(Item {
kwd,
kwd_str,
args,
split_args,
object,
}))
/// Return true iff 's' is a valid keyword or annotation.
/// (Only allow annotations if `anno_ok` is true.`
fn keyword_ok(mut s: &str, anno_ok: bool) -> bool {
/// Helper: return true if this character can appear in keywords.
fn kwd_char_ok(c: char) -> bool {
matches!(c,'A'..='Z' | 'a'..='z' |'0'..='9' | '-')
if s.is_empty() {
return false;
if anno_ok && s.starts_with('@') {
s = &s[1..];
if s.starts_with('-') {
s.chars().all(kwd_char_ok)
/// Return true iff 's' is a valid keyword for a BEGIN/END tag.
fn tag_keyword_ok(s: &str) -> bool {
s.split(' ').all(|w| keyword_ok(w, false))
/// When used as an Iterator, returns a sequence of Result<Item>.
impl<'a, K: Keyword> Iterator for NetDocReaderBase<'a, K> {
type Item = Result<Item<'a, K>>;
fn next(&mut self) -> Option<Self::Item> {
self.item().transpose()
/// Helper: as base64::decode(), but allows newlines in the middle of the
/// encoded object.
fn base64_decode_multiline(s: &str) -> std::result::Result<Vec<u8>, base64::DecodeError> {
// base64 module hates whitespace.
let mut v = Vec::new();
let mut s = s.to_string();
s.retain(|ch| ch != '\n');
base64::decode_config_buf(s, base64::STANDARD, &mut v)?;
Ok(v)
impl<'a, K: Keyword> Item<'a, K> {
/// Return the parsed keyword part of this item.
pub(crate) fn kwd(&self) -> K {
self.kwd
/// Return the keyword part of this item, as a string.
pub(crate) fn kwd_str(&self) -> &'a str {
self.kwd_str
/// Return true if the keyword for this item is in 'ks'.
pub(crate) fn has_kwd_in(&self, ks: &[K]) -> bool {
ks.contains(&self.kwd)
/// Return the arguments of this item, as a single string.
pub(crate) fn args_as_str(&self) -> &'a str {
self.args
/// Return the arguments of this item as a vector.
fn args_as_vec(&self) -> Ref<'_, Vec<&'a str>> {
// We're using an interior mutability pattern here to lazily
// construct the vector.
if self.split_args.borrow().is_none() {
self.split_args.replace(Some(self.args().collect()));
Ref::map(self.split_args.borrow(), |opt| match opt {
Some(v) => v,
None => panic!(),
})
/// Return an iterator over the arguments of this item.
pub(crate) fn args(&self) -> impl Iterator<Item = &'a str> {
self.args.split(is_sp).filter(|s| !s.is_empty())
/// Return the nth argument of this item, if there is one.
pub(crate) fn arg(&self, idx: usize) -> Option<&'a str> {
self.args_as_vec().get(idx).copied()
/// Return the nth argument of this item, or an error if it isn't there.
pub(crate) fn required_arg(&self, idx: usize) -> Result<&'a str> {
self.arg(idx)
.ok_or_else(|| EK::MissingArgument.at_pos(Pos::at(self.args)))
/// Try to parse the nth argument (if it exists) into some type
/// that supports FromStr.
/// Returns Ok(None) if the argument doesn't exist.
pub(crate) fn parse_optional_arg<V: FromStr>(&self, idx: usize) -> Result<Option<V>>
where
Error: From<V::Err>,
{
match self.arg(idx) {
None => Ok(None),
Some(s) => match s.parse() {
Ok(r) => Ok(Some(r)),
Err(e) => {
let e: Error = e.into();
Err(e.or_at_pos(Pos::at(s)))
},
/// Return an error if the argument doesn't exist.
pub(crate) fn parse_arg<V: FromStr>(&self, idx: usize) -> Result<V>
match self.parse_optional_arg(idx) {
Ok(Some(v)) => Ok(v),
Ok(None) => Err(EK::MissingArgument.at_pos(self.arg_pos(idx))),
Err(e) => Err(e),
/// Return the number of arguments for this Item
pub(crate) fn n_args(&self) -> usize {
self.args().count()
/// Return true iff this Item has an associated object.
pub(crate) fn has_obj(&self) -> bool {
self.object.is_some()
/// Return the tag of this item's associated object, if it has one.
pub(crate) fn obj_tag(&self) -> Option<&'a str> {
self.object.map(|o| o.tag)
/// Try to decode the base64 contents of this Item's associated object.
/// On success, return the object's tag and decoded contents.
pub(crate) fn obj_raw(&self) -> Result<Option<(&'a str, Vec<u8>)>> {
match self.object {
Some(obj) => {
let decoded = base64_decode_multiline(obj.data)
.map_err(|_| EK::BadObjectBase64.at_pos(Pos::at(obj.data)))?;
Ok(Some((obj.tag, decoded)))
/// Try to decode the base64 contents of this Item's associated object,
/// and make sure that its tag matches 'want_tag'.
pub(crate) fn obj(&self, want_tag: &str) -> Result<Vec<u8>> {
match self.obj_raw()? {
None => Err(EK::MissingObject
.with_msg(self.kwd.to_str())
.at_pos(self.end_pos())),
Some((tag, decoded)) => {
if tag != want_tag {
Err(EK::WrongObject.at_pos(Pos::at(tag)))
Ok(decoded)
/// Try to decode the base64 contents of this item's associated object
/// as a given type that implements FromBytes.
pub(crate) fn parse_obj<V: FromBytes>(&self, want_tag: &str) -> Result<V> {
let bytes = self.obj(want_tag)?;
// Unwrap may be safe because above `.obj()` should return an Error if
// wanted tag was not present
#[allow(clippy::unwrap_used)]
let p = Pos::at(self.object.unwrap().data);
V::from_vec(bytes, p).map_err(|e| e.at_pos(p))
/// Return the position of this item.
/// This position won't be useful unless it is later contextualized
/// with the containing string.
pub(crate) fn pos(&self) -> Pos {
Pos::at(self.kwd_str)
/// Return the position of this Item in a string.
/// Returns None if this item doesn't actually belong to the string.
pub(crate) fn offset_in(&self, s: &str) -> Option<usize> {
crate::util::str::str_offset(s, self.kwd_str)
/// Return the position of the n'th argument of this item.
/// If this item does not have a n'th argument, return the
/// position of the end of the final argument.
pub(crate) fn arg_pos(&self, n: usize) -> Pos {
let args = self.args_as_vec();
if n < args.len() {
Pos::at(args[n])
self.last_arg_end_pos()
/// Return the position at the end of the last argument. (This will
/// point to a newline.)
fn last_arg_end_pos(&self) -> Pos {
if args.len() >= 1 {
let last_arg = args[args.len() - 1];
Pos::at_end_of(last_arg)
Pos::at_end_of(self.kwd_str)
/// Return the position of the end of this object. (This will point to a
/// newline.)
pub(crate) fn end_pos(&self) -> Pos {
Some(o) => Pos::at_end_of(o.endline),
None => self.last_arg_end_pos(),
/// If this item occurs within s, return the byte offset
/// immediately after the end of this item.
pub(crate) fn offset_after(&self, s: &str) -> Option<usize> {
self.end_pos().offset_within(s).map(|nl_pos| nl_pos + 1)
/// Represents an Item that might not be present, whose arguments we
/// want to inspect. If the Item is there, this acts like a proxy to the
/// item; otherwise, it treats the item as having no arguments.
pub(crate) struct MaybeItem<'a, 'b, K: Keyword>(Option<&'a Item<'b, K>>);
// All methods here are as for Item.
impl<'a, 'b, K: Keyword> MaybeItem<'a, 'b, K> {
/// Return the position of this item, if it has one.
fn pos(&self) -> Pos {
match self.0 {
Some(item) => item.pos(),
None => Pos::None,
/// Construct a MaybeItem from an Option reference to an item.
pub(crate) fn from_option(opt: Option<&'a Item<'b, K>>) -> Self {
MaybeItem(opt)
/// If this item is present, parse its argument at position `idx`.
/// Treat the absence or malformedness of the argument as an error,
/// but treat the absence of this item as acceptable.
#[cfg(any(test, feature = "routerdesc"))]
pub(crate) fn parse_arg<V: FromStr>(&self, idx: usize) -> Result<Option<V>>
Some(item) => match item.parse_arg(idx) {
Ok(v) => Ok(Some(v)),
Err(e) => Err(e.or_at_pos(self.pos())),
/// If this item is present, return its arguments as a single string.
pub(crate) fn args_as_str(&self) -> Option<&str> {
self.0.map(|item| item.args_as_str())
/// If this item is present, parse all of its arguments as a
/// single string.
pub(crate) fn parse_args_as_str<V: FromStr>(&self) -> Result<Option<V>>
Some(item) => match item.args_as_str().parse::<V>() {
Err(e.or_at_pos(self.pos()))
/// Extension trait for Result<Item> -- makes it convenient to implement
/// PauseAt predicates
pub(crate) trait ItemResult<K: Keyword> {
/// Return true if this is an ok result with an annotation.
fn is_ok_with_annotation(&self) -> bool;
/// Return true if this is an ok result with a non-annotation.
fn is_ok_with_non_annotation(&self) -> bool;
/// Return true if this is an ok result with the keyword 'k'
fn is_ok_with_kwd(&self, k: K) -> bool {
self.is_ok_with_kwd_in(&[k])
/// Return true if this is an ok result with a keyword in the slice 'ks'
fn is_ok_with_kwd_in(&self, ks: &[K]) -> bool;
/// Return true if this is an ok result with a keyword not in the slice 'ks'
fn is_ok_with_kwd_not_in(&self, ks: &[K]) -> bool;
impl<'a, K: Keyword> ItemResult<K> for Result<Item<'a, K>> {
fn is_ok_with_annotation(&self) -> bool {
match self {
Ok(item) => item.kwd().is_annotation(),
Err(_) => false,
fn is_ok_with_non_annotation(&self) -> bool {
Ok(item) => !item.kwd().is_annotation(),
fn is_ok_with_kwd_in(&self, ks: &[K]) -> bool {
Ok(item) => item.has_kwd_in(ks),
fn is_ok_with_kwd_not_in(&self, ks: &[K]) -> bool {
Ok(item) => !item.has_kwd_in(ks),
/// A peekable cursor into a string that returns Items one by one.
pub(crate) struct NetDocReader<'a, K: Keyword> {
// TODO: I wish there were some way around having this string
// reference, since we already need one inside NetDocReaderBase.
/// The underlying string being parsed.
/// A stream of tokens being parsed by this NetDocReader.
tokens: std::iter::Peekable<NetDocReaderBase<'a, K>>,
impl<'a, K: Keyword> NetDocReader<'a, K> {
/// Construct a new NetDocReader to read tokens from `s`.
pub(crate) fn new(s: &'a str) -> Self {
NetDocReader {
tokens: NetDocReaderBase::new(s).peekable(),
/// Return a reference to the string used for this NetDocReader.
pub(crate) fn str(&self) -> &'a str {
self.s
/// Return the peekable iterator over the string's tokens.
pub(crate) fn iter(
&mut self,
) -> &mut std::iter::Peekable<impl Iterator<Item = Result<Item<'a, K>>>> {
&mut self.tokens
/// Return a PauseAt wrapper around the peekable iterator in this
/// NetDocReader that reads tokens until it reaches an element where
/// 'f' is true.
pub(crate) fn pause_at<F>(
f: F,
) -> PauseAt<'_, impl Iterator<Item = Result<Item<'a, K>>>, F>
F: FnMut(&Result<Item<'a, K>>) -> bool,
PauseAt::from_peekable(&mut self.tokens, f)
/// NetDocReader that returns all items.
#[allow(unused)]
pub(crate) fn pauseable(
) -> PauseAt<
'_,
impl Iterator<Item = Result<Item<'a, K>>>,
impl FnMut(&Result<Item<'a, K>>) -> bool,
> {
self.pause_at(|_| false)
/// Return true if there are no more items in this NetDocReader.
// The implementation sadly needs to mutate the inner state, even if it's not *semantically*
// mutated.. We don't want inner mutability just to placate clippy for an internal API.
#[allow(clippy::wrong_self_convention)]
pub(crate) fn is_exhausted(&mut self) -> bool {
self.iter().peek().is_none()
/// Give an error if there are remaining tokens in this NetDocReader.
pub(crate) fn should_be_exhausted(&mut self) -> Result<()> {
match self.iter().peek() {
None => Ok(()),
Some(Ok(t)) => Err(EK::UnexpectedToken
.with_msg(t.kwd().to_str())
.at_pos(t.pos())),
Some(Err(e)) => Err(e.clone()),
/// Return the position from which the underlying reader is about to take
/// the next token. Use to make sure that the reader is progressing.
pub(crate) fn pos(&mut self) -> Pos {
match self.tokens.peek() {
Some(Ok(tok)) => tok.pos(),
Some(Err(e)) => e.pos(),
None => Pos::at_end_of(self.s),
#[cfg(test)]
mod test {
#![allow(clippy::unwrap_used)]
#![allow(clippy::cognitive_complexity)]
use super::*;
use crate::parse::macros::test::Fruit;
use crate::{ParseErrorKind as EK, Pos, Result};
#[test]
fn read_simple() {
use Fruit::*;
let s = "\
@tasty very much so
opt apple 77
banana 60
cherry 6
-----BEGIN CHERRY SYNOPSIS-----
8J+NkvCfjZLwn42S8J+NkvCfjZLwn42S
-----END CHERRY SYNOPSIS-----
plum hello there
";
let mut r: NetDocReader<'_, Fruit> = NetDocReader::new(s);
assert_eq!(r.str(), s);
assert!(r.should_be_exhausted().is_err()); // it's not exhausted.
let toks: Result<Vec<_>> = r.iter().collect();
assert!(r.should_be_exhausted().is_ok());
let toks = toks.unwrap();
assert_eq!(toks.len(), 5);
assert_eq!(toks[0].kwd(), ANN_TASTY);
assert_eq!(toks[0].n_args(), 3);
assert_eq!(toks[0].args_as_str(), "very much so");
assert_eq!(toks[0].arg(1), Some("much"));
let a: Vec<_> = toks[0].args().collect();
assert_eq!(a, vec!["very", "much", "so"]);
assert!(toks[0].parse_arg::<usize>(0).is_err());
assert!(toks[0].parse_arg::<usize>(10).is_err());
assert!(!toks[0].has_obj());
assert_eq!(toks[0].obj_tag(), None);
assert_eq!(toks[2].pos().within(s), Pos::from_line(3, 1));
assert_eq!(toks[2].arg_pos(0).within(s), Pos::from_line(3, 8));
assert_eq!(toks[2].last_arg_end_pos().within(s), Pos::from_line(3, 10));
assert_eq!(toks[2].end_pos().within(s), Pos::from_line(3, 10));
assert_eq!(toks[3].kwd(), STONEFRUIT);
assert_eq!(toks[3].kwd_str(), "cherry"); // not cherry/plum!
assert_eq!(toks[3].n_args(), 1);
assert_eq!(toks[3].required_arg(0), Ok("6"));
assert_eq!(toks[3].parse_arg::<usize>(0), Ok(6));
assert_eq!(toks[3].parse_optional_arg::<usize>(0), Ok(Some(6)));
assert_eq!(toks[3].parse_optional_arg::<usize>(3), Ok(None));
assert!(toks[3].has_obj());
assert_eq!(toks[3].obj_tag(), Some("CHERRY SYNOPSIS"));
assert_eq!(
&toks[3].obj("CHERRY SYNOPSIS").unwrap()[..],
"🍒🍒🍒🍒🍒🍒".as_bytes()
assert!(toks[3].obj("PLUOT SYNOPSIS").is_err());
// this "end-pos" value is questionable!
assert_eq!(toks[3].end_pos().within(s), Pos::from_line(7, 30));
fn test_badtoks() {
-foobar 9090
apple 3.14159
$hello
unrecognized 127.0.0.1 foo
plum
-----BEGIN WHATEVER-----
-----END SOMETHING ELSE-----
orange
not! base64!
-----END WHATEVER-----
guava paste
opt @annotation
-----BEGIN LOBSTER
-----BEGIN !!!!!!-----
-----END !!!!!!-----
cherry
-----END CHERRY SYNOPSIS
truncated line";
let toks: Vec<_> = r.iter().collect();
assert!(toks[0].is_err());
toks[0].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(1, 1))
assert!(toks[1].is_ok());
assert!(toks[1].is_ok_with_non_annotation());
assert!(!toks[1].is_ok_with_annotation());
assert!(toks[1].is_ok_with_kwd_in(&[APPLE, ORANGE]));
assert!(toks[1].is_ok_with_kwd_not_in(&[ORANGE, UNRECOGNIZED]));
let t = toks[1].as_ref().unwrap();
assert_eq!(t.kwd(), APPLE);
assert_eq!(t.arg(0), Some("3.14159"));
assert!(toks[2].is_err());
assert!(!toks[2].is_ok_with_non_annotation());
assert!(!toks[2].is_ok_with_annotation());
assert!(!toks[2].is_ok_with_kwd_in(&[APPLE, ORANGE]));
assert!(!toks[2].is_ok_with_kwd_not_in(&[ORANGE, UNRECOGNIZED]));
toks[2].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(3, 1))
assert!(toks[3].is_ok());
let t = toks[3].as_ref().unwrap();
assert_eq!(t.kwd(), UNRECOGNIZED);
assert_eq!(t.arg(1), Some("foo"));
assert!(toks[4].is_err());
toks[4].as_ref().err().unwrap(),
&EK::BadObjectMismatchedTag.at_pos(Pos::from_line(8, 1))
assert!(toks[5].is_ok());
let t = toks[5].as_ref().unwrap();
assert_eq!(t.kwd(), ORANGE);
assert_eq!(t.args_as_str(), "");
// This blob counts as two errors: a bad base64 blob, and
// then an end line.
assert!(toks[6].is_err());
toks[6].as_ref().err().unwrap(),
&EK::BadObjectBase64.at_pos(Pos::from_line(12, 1))
assert!(toks[7].is_err());
toks[7].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(13, 1))
assert!(toks[8].is_ok());
let t = toks[8].as_ref().unwrap();
assert_eq!(t.kwd(), GUAVA);
// this is an error because you can't use opt with annotations.
assert!(toks[9].is_err());
toks[9].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(15, 1))
// this looks like a few errors.
assert!(toks[10].is_err());
toks[10].as_ref().err().unwrap(),
&EK::BadObjectBeginTag.at_pos(Pos::from_line(17, 1))
assert!(toks[11].is_err());
toks[11].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(18, 1))
assert!(toks[12].is_err());
toks[12].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(19, 1))
// so does this.
assert!(toks[13].is_err());
toks[13].as_ref().err().unwrap(),
&EK::BadObjectBeginTag.at_pos(Pos::from_line(21, 1))
assert!(toks[14].is_err());
toks[14].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(22, 1))
assert!(toks[15].is_err());
toks[15].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(23, 1))
// not this.
assert!(toks[16].is_err());
toks[16].as_ref().err().unwrap(),
&EK::BadObjectEndTag.at_pos(Pos::from_line(27, 1))
assert!(toks[17].is_err());
toks[17].as_ref().err().unwrap(),
&EK::BadKeyword.at_pos(Pos::from_line(28, 1))
assert!(toks[18].is_err());
toks[18].as_ref().err().unwrap(),
&EK::TruncatedLine.at_pos(Pos::from_line(29, 15))