Add InputReader

Signed-off-by: trivernis <trivernis@protonmail.com>
pull/1/head
trivernis 3 years ago
parent e58a34820e
commit b0532856d5
Signed by: Trivernis
GPG Key ID: DFFFCC2C7A02DB45

@ -1,6 +1,6 @@
[package]
name = "charred"
version = "0.3.6"
version = "2.0.0"
authors = ["trivernis <trivernis@protonmail.com>"]
edition = "2018"
license-file = "LICENSE"
@ -12,3 +12,13 @@ repository = "https://github.com/Trivernis/charred-rs"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
thiserror = "1.0.24"
log = "0.4.14"
[dependencies.tokio]
version = "1.5.0"
features = ["io-util", "io-std"]
[dev-dependencies.tokio]
version = "1.5.0"
features = ["rt-multi-thread", "test-util"]

@ -0,0 +1,9 @@
use thiserror::Error;
pub type TapeResult<T> = Result<T, TapeError>;
#[derive(Debug, Error)]
pub enum TapeError {
#[error("IO Error: {0}")]
TokioIoError(#[from] tokio::io::Error),
}

@ -0,0 +1,50 @@
use crate::error::TapeResult;
use crate::traits::AsyncReadSeek;
use std::io::SeekFrom;
use tokio::io::{AsyncReadExt, BufReader};
use tokio::io::{AsyncSeekExt, ErrorKind};
/// An Input reader to asynchronously read a type
/// that implements AsyncBufRead and AsyncSeek.
pub struct InputReader {
inner: BufReader<Box<dyn AsyncReadSeek>>,
}
impl InputReader {
pub fn new<T: AsyncReadSeek + 'static>(inner: T) -> Self {
Self {
inner: BufReader::new(Box::new(inner)),
}
}
/// Reads the next char consuming it in the process
pub async fn consume(&mut self) -> TapeResult<char> {
self.read_next().await
}
/// Returns the next char without forwarding
pub async fn peek(&mut self) -> TapeResult<char> {
let char = self.read_next().await?;
self.inner.get_mut().seek(SeekFrom::Current(-1)).await?;
Ok(char)
}
/// Returns if EOF has been reached
pub async fn check_eof(&mut self) -> TapeResult<bool> {
let char = self.read_next().await?;
Ok(char == '\x00')
}
/// Reads the next char returning \x00 for EOF
async fn read_next(&mut self) -> TapeResult<char> {
let mut value = String::with_capacity(1);
match self.inner.read_to_string(&mut value).await {
Ok(_) => Ok(value.chars().next().unwrap()),
Err(e) if e.kind() == ErrorKind::UnexpectedEof => Ok('\x00'),
Err(e) => Err(e.into()),
}
}
}

@ -1,82 +1,3 @@
pub mod tapemachine;
#[cfg(test)]
mod tests {
use crate::tapemachine::TapeResult;
use crate::tapemachine::{CharTapeMachine, TapeError};
const TEST_STRING: &str = "TEST STRING 1234 \\l \\n";
#[test]
fn it_returns_the_next_char() {
let mut ctm = CharTapeMachine::new(TEST_STRING.chars().collect());
let test_chars: Vec<char> = TEST_STRING.chars().collect();
let mut next = ctm.next_char().unwrap();
assert_eq!(next, *test_chars.get(1).unwrap());
next = ctm.next_char().unwrap();
assert_eq!(next, *test_chars.get(2).unwrap());
let _ = ctm.next_char().unwrap();
let _ = ctm.next_char().unwrap();
let _ = ctm.next_char().unwrap();
next = ctm.next_char().unwrap();
assert_eq!(next, *test_chars.get(6).unwrap());
}
#[test]
fn it_rewinds() {
let mut ctm = CharTapeMachine::new(TEST_STRING.chars().collect());
let test_chars: Vec<char> = TEST_STRING.chars().collect();
ctm.next_char().unwrap();
ctm.next_char().unwrap();
assert_eq!(ctm.next_char(), Some(*test_chars.get(3).unwrap()));
ctm.rewind(1);
assert_eq!(ctm.next_char(), Some(*test_chars.get(2).unwrap()));
}
#[test]
fn it_seeks() {
let mut ctm = CharTapeMachine::new(TEST_STRING.chars().collect());
let test_chars: Vec<char> = TEST_STRING.chars().collect();
assert_eq!(ctm.next_char(), Some(*test_chars.get(1).unwrap()));
ctm.seek_one().unwrap();
assert_eq!(ctm.next_char(), Some(*test_chars.get(3).unwrap()));
ctm.seek_one().unwrap();
ctm.seek_whitespace();
assert_eq!(ctm.next_char(), Some(*test_chars.get(6).unwrap()));
}
#[test]
fn it_asserts_chars() -> TapeResult<()> {
let mut ctm = CharTapeMachine::new(TEST_STRING.chars().collect());
ctm.assert_any(&['A', 'B', 'T'], None)?;
ctm.seek_one().unwrap();
ctm.assert_char(&'E', None)?;
ctm.seek_one().unwrap();
ctm.assert_str_sequence("ST ", None)?;
ctm.seek_one().unwrap();
ctm.assert_any_sequence(&[&['C'], &['A'], &['A', 'B'], &['S', 'T', 'R']], None)?;
if let Ok(_) =
ctm.assert_any_sequence(&[&['C'], &['A'], &['A', 'B'], &['S', 'T', 'R']], None)
{
Err(TapeError::new(0))
} else {
Ok(())
}
}
#[test]
fn it_checks_eof() -> TapeResult<()> {
let mut ctm = CharTapeMachine::new(TEST_STRING.chars().collect());
let _ = ctm.get_string_until_any(&['n'], &[]);
assert!(ctm.check_eof());
Ok(())
}
}
pub mod error;
pub mod input;
mod traits;

@ -1,424 +0,0 @@
use std::error::Error;
use std::fmt::{self, Display, Formatter};
#[derive(Debug)]
pub struct TapeError {
index: usize,
}
impl TapeError {
pub fn new(index: usize) -> Self {
Self { index }
}
/// Returns the index the error occured on
pub fn get_index(&self) -> usize {
self.index
}
}
impl Display for TapeError {
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
write!(f, "Tape Error at: {}", self.index)
}
}
impl Error for TapeError {}
pub type TapeResult<T> = Result<T, TapeError>;
const ESCAPE: char = '\\';
pub struct CharTapeMachine {
index: usize,
text: Vec<char>,
current_char: char,
previous_char: char,
}
impl CharTapeMachine {
pub fn new(text: Vec<char>) -> Self {
let current_char = if text.len() > 0 {
*text.first().unwrap()
} else {
' '
};
Self {
text,
index: 0,
previous_char: current_char,
current_char,
}
}
#[inline]
pub fn get_text(&self) -> Vec<char> {
self.text.clone()
}
#[inline]
pub fn get_index(&self) -> usize {
self.index
}
/// returns the current char
#[inline]
pub fn get_current(&self) -> char {
self.current_char
}
/// Creates an error at the current position
#[inline]
pub fn err(&self) -> TapeError {
TapeError::new(self.index)
}
/// Returns the next char
/// if there is any
pub fn next_char(&mut self) -> Option<char> {
if self.index < self.text.len() {
self.index += 1;
self.previous_char = self.current_char;
self.current_char = *self.text.get(self.index)?;
Some(self.current_char)
} else {
None
}
}
/// Peeks the next available char
#[inline]
pub fn peek_char(&mut self) -> Option<char> {
Some(*self.text.get(self.index + 1)?)
}
/// Rewinds to a given index
#[inline]
pub fn rewind(&mut self, index: usize) {
if self.text.len() > index {
self.index = index;
self.current_char = *self.text.get(index).unwrap();
if self.index > 0 {
self.previous_char = *self.text.get(index - 1).unwrap();
}
}
}
/// Rewinds to a given index and returns an error
#[inline]
pub fn rewind_with_error(&mut self, index: usize) -> TapeError {
self.rewind(index);
TapeError::new(index)
}
/// Seeks one character or returns an error
/// if there is no next character
#[inline]
pub fn seek_one(&mut self) -> TapeResult<()> {
if let Some(_) = self.next_char() {
Ok(())
} else {
Err(TapeError::new(self.index))
}
}
/// Seeks one character and returns
/// if it seeked or an error occurred
#[inline]
pub fn try_seek(&mut self) -> bool {
self.seek_one().is_ok()
}
/// Seeks any character of the given group until none is encountered anymore
pub fn seek_any(&mut self, chars: &[char]) -> TapeResult<()> {
while self.check_any(chars) {
self.seek_one()?;
}
Ok(())
}
/// Seeks until it encounters a non whitespace character
pub fn seek_whitespace(&mut self) {
if self.current_char.is_whitespace() {
while let Some(next) = self.next_char() {
if !next.is_whitespace() || self.check_escaped() {
break;
}
}
}
}
/// Checks if the machine has reached the eof
pub fn check_eof(&self) -> bool {
self.index >= self.text.len()
}
/// checks if the current char is escaped
#[inline]
pub fn check_escaped(&mut self) -> bool {
let start = self.index;
let escaped = if self.previous_char == ESCAPE {
self.rewind(start - 1);
!self.check_escaped()
} else {
false
};
self.rewind(start);
escaped
}
/// Returns true if the given character is equal to the current one
/// and the current character is not escaped
#[inline]
pub fn check_char(&mut self, value: &char) -> bool {
self.current_char == *value && !self.check_escaped()
}
/// Checks if one of the given chars matches the current one
#[inline]
pub fn check_any(&mut self, chars: &[char]) -> bool {
!self.check_escaped() && chars.contains(&self.current_char)
}
/// checks if the next characters match a given sequence of characters
pub fn check_sequence(&mut self, sequence: &[char]) -> bool {
let start_index = self.index;
if self.check_escaped() {
self.rewind(start_index);
false
} else {
for sq_character in sequence {
if self.current_char != *sq_character {
self.rewind(start_index);
return false;
}
if self.next_char() == None {
self.rewind(start_index);
return false;
}
}
if self.index > 0 {
self.rewind(self.index - 1);
}
true
}
}
// checks if the next characters mach a string sequence
pub fn check_str_sequence(&mut self, sequence: &str) -> bool {
let start_index = self.index;
if self.check_escaped() {
self.rewind(start_index);
false
} else {
let matches = sequence.chars().all(|sq_character| {
if self.current_char != sq_character {
self.rewind(start_index);
return false;
}
if self.next_char() == None {
self.rewind(start_index);
return false;
}
true
});
if !matches {
false
} else {
if self.index > 0 {
self.rewind(self.index - 1);
}
true
}
}
}
/// checks if the next characters match any given sequence
#[inline]
pub fn check_any_sequence(&mut self, sequences: &[&[char]]) -> bool {
for seq in sequences {
if self.check_sequence(*seq) {
return true;
}
}
false
}
/// checks if the next characters match any given sequence of strings
#[inline]
pub fn check_any_str_sequence(&mut self, sequences: &[&str]) -> bool {
for str_seq in sequences {
if self.check_str_sequence(str_seq) {
return true;
}
}
false
}
/// returns an error on the current position and optionally rewinds
/// if a rewind index is given
#[inline]
pub fn assert_error(&mut self, rewind_index: Option<usize>) -> TapeError {
if let Some(index) = rewind_index {
self.rewind_with_error(index)
} else {
TapeError::new(self.index)
}
}
/// returns an error if the given char doesn't match the current one and rewinds
/// if a rewind index is given
#[inline]
pub fn assert_char(&mut self, value: &char, rewind_index: Option<usize>) -> TapeResult<()> {
if self.check_char(value) {
Ok(())
} else {
Err(self.assert_error(rewind_index))
}
}
/// returns an error if the current char doesn't match any of the given group
#[inline]
pub fn assert_any(&mut self, chars: &[char], rewind_index: Option<usize>) -> TapeResult<()> {
if self.check_any(chars) {
Ok(())
} else {
Err(self.assert_error(rewind_index))
}
}
/// returns an error if the next chars don't match a special sequence
#[inline]
pub fn assert_sequence(
&mut self,
sequence: &[char],
rewind_index: Option<usize>,
) -> TapeResult<()> {
if self.check_sequence(sequence) {
Ok(())
} else {
Err(self.assert_error(rewind_index))
}
}
/// returns an error if the next chars don't match a special sequence
#[inline]
pub fn assert_str_sequence(
&mut self,
sequence: &str,
rewind_index: Option<usize>,
) -> TapeResult<()> {
if self.check_str_sequence(sequence) {
Ok(())
} else {
Err(self.assert_error(rewind_index))
}
}
/// returns an error if the next chars don't match any given sequence
pub fn assert_any_sequence(
&mut self,
sequences: &[&[char]],
rewind_index: Option<usize>,
) -> TapeResult<()> {
if self.check_any_sequence(sequences) {
Ok(())
} else {
Err(self.assert_error(rewind_index))
}
}
/// returns an error if the next chars don't match any given sequence
pub fn assert_any_str_sequence(
&mut self,
sequences: &[&str],
rewind_index: Option<usize>,
) -> TapeResult<()> {
if self.check_any_str_sequence(sequences) {
Ok(())
} else {
Err(self.assert_error(rewind_index))
}
}
/// returns the string until any given character is matched is matched.
/// rewinds with error if it encounters a character form the error group
#[inline]
pub fn get_string_until_any(&mut self, until: &[char], err_at: &[char]) -> TapeResult<String> {
let start_index = self.index;
self.get_string_until_any_or_rewind(until, err_at, start_index)
}
/// Returns the string until it encounters a given sequence or rewinds with error
/// if it encounters an err sequence
pub fn get_string_until_sequence(
&mut self,
until: &[&[char]],
err_at: &[&[char]],
) -> Result<String, TapeError> {
let start_index = self.index;
let mut result = String::new();
if self.check_any_sequence(until) {
return Ok(result);
} else if self.check_any_sequence(err_at) {
return Err(TapeError::new(self.index));
}
result.push(self.current_char);
while let Some(ch) = self.next_char() {
if self.check_any_sequence(until) || self.check_any_sequence(err_at) {
break;
}
result.push(ch);
}
if self.check_any_sequence(err_at) {
Err(self.rewind_with_error(start_index))
} else {
Ok(result)
}
}
/// returns the string until a special char is found
/// or rewinds if an err_at char is found
pub fn get_string_until_any_or_rewind(
&mut self,
until: &[char],
err_at: &[char],
rewind_index: usize,
) -> TapeResult<String> {
let mut result = String::new();
if self.check_any(until) {
return Ok(result);
} else if self.check_any(err_at) {
return Err(self.rewind_with_error(rewind_index));
}
result.push(self.current_char);
while let Some(ch) = self.next_char() {
if self.check_any(until) || self.check_any(err_at) {
break;
}
result.push(ch);
}
if self.check_any(err_at) {
Err(self.rewind_with_error(rewind_index))
} else {
Ok(result)
}
}
}

@ -0,0 +1,3 @@
use tokio::io::{AsyncRead, AsyncSeek};
pub trait AsyncReadSeek: AsyncRead + AsyncSeek + Unpin {}
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