Handle the escapes of quote in the filters

This commit is contained in:
Tamo 2021-12-20 16:18:15 +01:00
parent 11a056d116
commit 02a21fd309
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GPG Key ID: 20CD8020AFA88D69
3 changed files with 197 additions and 23 deletions

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@ -56,6 +56,7 @@ pub enum ErrorKind<'a> {
InvalidPrimary,
ExpectedEof,
ExpectedValue,
MalformedValue,
MissingClosingDelimiter(char),
Char(char),
InternalError(error::ErrorKind),
@ -82,7 +83,7 @@ impl<'a> Error<'a> {
pub fn char(self) -> char {
match self.kind {
ErrorKind::Char(c) => c,
_ => panic!("Internal filter parser error"),
error => panic!("Internal filter parser error: {:?}", error),
}
}
}
@ -117,6 +118,9 @@ impl<'a> Display for Error<'a> {
ErrorKind::ExpectedValue if input.trim().is_empty() => {
writeln!(f, "Was expecting a value but instead got nothing.")?
}
ErrorKind::MalformedValue => {
writeln!(f, "Malformed value: `{}`.", escaped_input)?
}
ErrorKind::MissingClosingDelimiter(c) => {
writeln!(f, "Expression `{}` is missing the following closing delimiter: `{}`.", escaped_input, c)?
}

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@ -62,29 +62,39 @@ pub type Span<'a> = LocatedSpan<&'a str, &'a str>;
type IResult<'a, Ret> = nom::IResult<Span<'a>, Ret, Error<'a>>;
#[derive(Debug, Clone, Eq)]
pub struct Token<'a>(Span<'a>);
pub struct Token<'a> {
/// The token in the original input, it should be used when possible.
span: Span<'a>,
/// If you need to modify the original input you can use the `value` field
/// to store your modified input.
value: Option<String>,
}
impl<'a> Deref for Token<'a> {
type Target = &'a str;
fn deref(&self) -> &Self::Target {
&self.0
&self.span
}
}
impl<'a> PartialEq for Token<'a> {
fn eq(&self, other: &Self) -> bool {
self.0.fragment() == other.0.fragment()
self.span.fragment() == other.span.fragment()
}
}
impl<'a> Token<'a> {
pub fn new(position: Span<'a>) -> Self {
Self(position)
pub fn new(span: Span<'a>, value: Option<String>) -> Self {
Self { span, value }
}
pub fn value(&self) -> &str {
self.value.as_ref().map_or(&self.span, |value| value)
}
pub fn as_external_error(&self, error: impl std::error::Error) -> Error<'a> {
Error::new_from_external(self.0, error)
Error::new_from_external(self.span, error)
}
pub fn parse<T>(&self) -> Result<T, Error>
@ -92,13 +102,13 @@ impl<'a> Token<'a> {
T: FromStr,
T::Err: std::error::Error,
{
self.0.parse().map_err(|e| self.as_external_error(e))
self.span.parse().map_err(|e| self.as_external_error(e))
}
}
impl<'a> From<Span<'a>> for Token<'a> {
fn from(span: Span<'a>) -> Self {
Self(span)
Self { span, value: None }
}
}

View File

@ -7,8 +7,54 @@ use nom::sequence::{delimited, terminated};
use crate::error::NomErrorExt;
use crate::{parse_geo_point, parse_geo_radius, Error, ErrorKind, IResult, Span, Token};
/// This function goes through all chacaters in the [Span], if it finds any escaped character (`\`).
/// It generate a new string with all `\` removed from the [Span].
fn unescape(buf: Span, char_to_escape: char) -> String {
let to_escape = format!("\\{}", char_to_escape);
buf.replace(&to_escape, &char_to_escape.to_string())
}
use nom::{InputIter, InputLength, InputTake, Slice};
/// Parse a value in quote. If it encounter an escaped quote it'll unescape it.
fn quoted_by(quote: char, input: Span) -> IResult<Token> {
// empty fields / values are valid in json
if input.is_empty() {
return Ok((input.slice(input.input_len()..), input.into()));
}
let mut escaped = false;
let mut i = input.iter_indices();
while let Some((idx, c)) = i.next() {
match c {
c if c == quote => {
let (rem, output) = input.take_split(idx);
return Ok((rem, Token::new(output, escaped.then(|| unescape(output, quote)))));
}
'\\' => {
if let Some((_, c)) = i.next() {
escaped |= c == quote;
} else {
return Err(nom::Err::Error(Error::new_from_kind(
input,
ErrorKind::MalformedValue,
)));
}
}
// if it was preceeded by a `\` or if it was anything else we can continue to advance
_ => (),
}
}
Ok((
input.slice(input.input_len()..),
Token::new(input, escaped.then(|| unescape(input, quote))),
))
}
/// value = WS* ~ ( word | singleQuoted | doubleQuoted) ~ WS*
pub fn parse_value(input: Span) -> IResult<Token> {
pub fn parse_value<'a>(input: Span<'a>) -> IResult<Token<'a>> {
// to get better diagnostic message we are going to strip the left whitespaces from the input right now
let (input, _) = take_while(char::is_whitespace)(input)?;
@ -30,12 +76,10 @@ pub fn parse_value(input: Span) -> IResult<Token> {
_ => (),
}
// singleQuoted = "'" .* all but quotes "'"
let simple_quoted = take_till(|c: char| c == '\'');
// doubleQuoted = "\"" (word | spaces)* "\""
let double_quoted = take_till(|c: char| c == '"');
// word = (alphanumeric | _ | - | .)+
let word = take_while1(is_value_component);
let word = |input: Span<'a>| -> IResult<Token<'a>> {
take_while1(is_value_component)(input).map(|(s, t)| (s, t.into()))
};
// this parser is only used when an error is encountered and it parse the
// largest string possible that do not contain any “language” syntax.
@ -48,20 +92,27 @@ pub fn parse_value(input: Span) -> IResult<Token> {
terminated(
alt((
delimited(char('\''), cut(simple_quoted), cut(char('\''))),
delimited(char('"'), cut(double_quoted), cut(char('"'))),
delimited(char('\''), cut(|input| quoted_by('\'', input)), cut(char('\''))),
delimited(char('"'), cut(|input| quoted_by('"', input)), cut(char('"'))),
word,
)),
multispace0,
)(input)
.map(|(s, t)| (s, t.into()))
// .map(|(s, t)| (s, t.into()))
// if we found nothing in the alt it means the user specified something that was not recognized as a value
.map_err(|e: nom::Err<Error>| {
e.map_err(|_| Error::new_from_kind(error_word(input).unwrap().1, ErrorKind::ExpectedValue))
})
// if we found encountered a failure it means the user really tried to input a value, but had an unmatched quote
.map_err(|e| {
e.map_fail(|c| Error::new_from_kind(input, ErrorKind::MissingClosingDelimiter(c.char())))
e.map_fail(|failure| {
// if we found encountered a char failure it means the user had an unmatched quote
if matches!(failure.kind(), ErrorKind::Char(_)) {
Error::new_from_kind(input, ErrorKind::MissingClosingDelimiter(failure.char()))
} else {
// else we let the failure untouched
failure
}
})
})
}
@ -81,7 +132,7 @@ pub mod test {
use crate::tests::rtok;
#[test]
fn name() {
fn test_span() {
let test_case = [
("channel", rtok("", "channel")),
(".private", rtok("", ".private")),
@ -102,6 +153,7 @@ pub mod test {
("\"cha'nnel\"", rtok("'", "cha'nnel")),
("\"cha'nnel\"", rtok("'", "cha'nnel")),
("I'm tamo", rtok("'m tamo", "I")),
("\"I'm \\\"super\\\" tamo\"", rtok("\"", "I'm \\\"super\\\" tamo")),
];
for (input, expected) in test_case {
@ -114,8 +166,116 @@ pub mod test {
expected,
result.unwrap_err()
);
let value = result.unwrap().1;
assert_eq!(value, expected, "Filter `{}` failed.", input);
let token = result.unwrap().1;
assert_eq!(token, expected, "Filter `{}` failed.", input);
}
}
#[test]
fn test_escape_inside_double_quote() {
// (input, remaining, expected output token, output value)
let test_case = [
("aaaa", "", rtok("", "aaaa"), "aaaa"),
(r#"aa"aa"#, r#""aa"#, rtok("", "aa"), "aa"),
(r#"aa\"aa"#, r#""#, rtok("", r#"aa\"aa"#), r#"aa"aa"#),
(r#"aa\\\aa"#, r#""#, rtok("", r#"aa\\\aa"#), r#"aa\\\aa"#),
(r#"aa\\"\aa"#, r#""\aa"#, rtok("", r#"aa\\"#), r#"aa\\"#),
(r#"aa\\\"\aa"#, r#""#, rtok("", r#"aa\\\"\aa"#), r#"aa\\"\aa"#),
(r#"\"\""#, r#""#, rtok("", r#"\"\""#), r#""""#),
];
for (input, remaining, expected_tok, expected_val) in test_case {
let span = Span::new_extra(input, "");
let result = quoted_by('"', span);
assert!(result.is_ok());
let (rem, output) = result.unwrap();
assert_eq!(rem.to_string(), remaining);
assert_eq!(output, expected_tok);
assert_eq!(output.value(), expected_val.to_string());
}
}
#[test]
fn test_unescape() {
// double quote
assert_eq!(
unescape(Span::new_extra(r#"Hello \"World\""#, ""), '"'),
r#"Hello "World""#.to_string()
);
assert_eq!(
unescape(Span::new_extra(r#"Hello \\\"World\\\""#, ""), '"'),
r#"Hello \\"World\\""#.to_string()
);
// simple quote
assert_eq!(
unescape(Span::new_extra(r#"Hello \'World\'"#, ""), '\''),
r#"Hello 'World'"#.to_string()
);
assert_eq!(
unescape(Span::new_extra(r#"Hello \\\'World\\\'"#, ""), '\''),
r#"Hello \\'World\\'"#.to_string()
);
}
#[test]
fn test_value() {
let test_case = [
// (input, expected value, if a string was generated to hold the new value)
("channel", "channel", false),
// All the base test, no escaped string should be generated
(".private", ".private", false),
("I-love-kebab", "I-love-kebab", false),
("but_snakes_is_also_good", "but_snakes_is_also_good", false),
("parens(", "parens", false),
("parens)", "parens", false),
("not!", "not", false),
(" channel", "channel", false),
("channel ", "channel", false),
(" channel ", "channel", false),
("'channel'", "channel", false),
("\"channel\"", "channel", false),
("'cha)nnel'", "cha)nnel", false),
("'cha\"nnel'", "cha\"nnel", false),
("\"cha'nnel\"", "cha'nnel", false),
("\" some spaces \"", " some spaces ", false),
("\"cha'nnel\"", "cha'nnel", false),
("\"cha'nnel\"", "cha'nnel", false),
("I'm tamo", "I", false),
// escaped thing but not quote
(r#""\\""#, r#"\\"#, false),
(r#""\\\\\\""#, r#"\\\\\\"#, false),
(r#""aa\\aa""#, r#"aa\\aa"#, false),
// with double quote
(r#""Hello \"world\"""#, r#"Hello "world""#, true),
(r#""Hello \\\"world\\\"""#, r#"Hello \\"world\\""#, true),
(r#""I'm \"super\" tamo""#, r#"I'm "super" tamo"#, true),
(r#""\"\"""#, r#""""#, true),
// with simple quote
(r#"'Hello \'world\''"#, r#"Hello 'world'"#, true),
(r#"'Hello \\\'world\\\''"#, r#"Hello \\'world\\'"#, true),
(r#"'I\'m "super" tamo'"#, r#"I'm "super" tamo"#, true),
(r#"'\'\''"#, r#"''"#, true),
];
for (input, expected, escaped) in test_case {
let input = Span::new_extra(input, input);
let result = parse_value(input);
assert!(
result.is_ok(),
"Filter `{:?}` was supposed to be parsed but failed with the following error: `{}`",
expected,
result.unwrap_err()
);
let token = result.unwrap().1;
assert_eq!(
token.value.is_some(),
escaped,
"Filter `{}` was not supposed to be escaped",
input
);
assert_eq!(token.value(), expected, "Filter `{}` failed.", input);
}
}