You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: source.rs
    path of file: ./repos/oxc/crates/oxc_parser/src/lexer
    
    the code of the file until where you have to start completion: #![allow(clippy::unnecessary_safety_comment)]

use super::search::SEARCH_BATCH_SIZE;
use crate::{UniquePromise, MAX_LEN};

use std::{marker::Phant
    
    pub(super) unsafe fn peek_byte_unchecked(&self) -> u8 {
        // SAFETY: Caller guarantees `ptr` is before `end` (i.e. not at end of file).
        // Methods of this type provide no way to allow `ptr` to be before `start`.
        // `Source`'s invariants guarantee that `self.start` - `self.end` contains allocated memory.
        // `Source::new` takes an immutable ref `&str`, guaranteeing that the memory `self.ptr`
        // addresses cannot be aliased by a `&mut` ref as long as `Source` exists.
        debug_assert!(self.ptr >= self.start && self.ptr < self.end);
        self.position().read()
    }