cursor.rs — tailwindcss Source File

Source Code

use std::{ascii::escape_default, fmt::Display};

#[derive(Debug, Clone)]
pub struct Cursor<'a> {
    // The input we're scanning
    pub input: &'a [u8],

    // The location of the cursor in the input
    pub pos: usize,

    /// Is the cursor at the start of the input
    pub at_start: bool,

    /// Is the cursor at the end of the input
    pub at_end: bool,

    /// The previously consumed character
    /// If `at_start` is true, this will be NUL
    pub prev: u8,

    /// The current character
    pub curr: u8,

    /// The upcoming character (if any)
    /// If `at_end` is true, this will be NUL
    pub next: u8,
}

impl<'a> Cursor<'a> {
    pub fn new(input: &'a [u8]) -> Self {
        let mut cursor = Self {
            input,
            pos: 0,
            at_start: true,
            at_end: false,
            prev: 0x00,
            curr: 0x00,
            next: 0x00,
        };
        cursor.move_to(0);
        cursor
    }

    pub fn advance_by(&mut self, amount: usize) {
        self.move_to(self.pos.saturating_add(amount));
    }

    #[inline(always)]
    pub fn advance(&mut self) {
        self.pos += 1;

        self.prev = self.curr;
        self.curr = self.next;
        self.next = *self
            .input
            .get(self.pos.saturating_add(1))
            .unwrap_or(&0x00u8);
    }

    #[inline(always)]
// ... (101 more lines)