minify-html/rust/onepass/src/err.rs

135 lines
4.1 KiB
Rust

/// Represents the type of minification error.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum ErrorType {
ClosingTagMismatch { expected: String, got: String },
NotFound(&'static str),
UnexpectedEnd,
UnexpectedClosingTag,
}
impl std::fmt::Display for ErrorType {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
ErrorType::ClosingTagMismatch { expected, got } => {
write!(f,
"closing tag name does not match opening tag (expected \"{}\", got \"{}\")",
expected, got
)
}
ErrorType::NotFound(exp) => {
write!(f, "expected {}", exp)
}
ErrorType::UnexpectedEnd => {
f.write_str("unexpected end of source code")
}
ErrorType::UnexpectedClosingTag => {
f.write_str("unexpected closing tag")
}
}
}
}
/// Details about a minification failure, including where it occurred and why.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct Error {
pub error_type: ErrorType,
pub position: usize,
}
impl std::fmt::Display for Error {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "At {}, {}", self.position, self.error_type)
}
}
/// User-friendly details about a minification failure, including an English message description of
/// the reason, and generated printable contextual representation of the code where the error
/// occurred.
#[derive(Debug)]
pub struct FriendlyError {
pub position: usize,
pub message: String,
pub code_context: String,
}
pub type ProcessingResult<T> = Result<T, ErrorType>;
#[inline(always)]
fn maybe_mark_indicator(
line: &mut Vec<u8>,
marker: u8,
maybe_pos: isize,
lower: usize,
upper: usize,
) -> bool {
let pos = maybe_pos as usize;
if maybe_pos > -1 && pos >= lower && pos < upper {
let pos_in_line = pos - lower;
while line.len() <= pos_in_line {
line.push(b' ');
}
line.insert(
pos_in_line,
if line[pos_in_line] != b' ' {
b'B'
} else {
marker
},
);
true
} else {
false
}
}
// Pass -1 for read_pos or write_pos to prevent them from being represented.
pub fn debug_repr(code: &[u8], read_pos: isize, write_pos: isize) -> String {
let only_one_pos = read_pos == -1 || write_pos == -1;
let read_marker = if only_one_pos { b'^' } else { b'R' };
let write_marker = if only_one_pos { b'^' } else { b'W' };
let mut lines = Vec::<(isize, String)>::new();
let mut cur_pos = 0;
for (line_no, line) in code.split(|c| *c == b'\n').enumerate() {
// Include '\n'. Note that the last line might not have '\n' but that's OK for these calculations.
let len = line.len() + 1;
let line_as_string = unsafe { String::from_utf8_unchecked(line.to_vec()) };
lines.push(((line_no + 1) as isize, line_as_string));
let new_pos = cur_pos + len;
// Rust does lazy allocation by default, so this is not wasteful.
let mut indicator_line = Vec::new();
maybe_mark_indicator(
&mut indicator_line,
write_marker,
write_pos,
cur_pos,
new_pos,
);
let marked_read =
maybe_mark_indicator(&mut indicator_line, read_marker, read_pos, cur_pos, new_pos);
if !indicator_line.is_empty() {
lines.push((-1, unsafe { String::from_utf8_unchecked(indicator_line) }));
};
cur_pos = new_pos;
if marked_read {
break;
};
}
let line_no_col_width = lines.len().to_string().len();
let mut res = String::new();
for (line_no, line) in lines {
res.push_str(&format!(
"{:>indent$}|{}\n",
if line_no == -1 {
">".repeat(line_no_col_width)
} else {
line_no.to_string()
},
line,
indent = line_no_col_width,
));
}
res
}