Crate scolapasta_string_escape

Routines for debug escaping Ruby Strings.

Ruby Strings are conventionally UTF-8 byte sequences. When calling String#inspect or Symbol#inspect, these maybe UTF-8 byte strings are escaped to have a valid and printable UTF-8 representation.

This crate exposes functions and iterators for encoding arbitrary byte slices as valid, printable UTF-8.

Ruby debug escapes

Ruby produces debug escapes that look like:

[2.6.3] > "Artichoke Ruby is made with Rust.

Invalid UTF-8: \xFF.

Slash \\ and quote \" are escaped."
=> "Artichoke Ruby is made with Rust.\n\nInvalid UTF-8: \xFF.\n\nSlash \\ and quote \" are escaped."

Ruby escape sequences differ than Rust escape sequences for some characters. For example 0x0C:

// Rust
assert_eq!('\x0C'.escape_debug().collect::<String>(), r"\u{c}");
// Ruby
assert_eq!(Literal::from(0x0C).as_str(), r"\f");

Examples

const EXAMPLE: &[u8] = b"Artichoke Ruby is made with Rust.

Invalid UTF-8: \xFF.

Slash \\ and quote \" are escaped.";

let mut escaped = String::new();
format_debug_escape_into(&mut escaped, EXAMPLE)?;
assert_eq!(
    escaped,
    r#"Artichoke Ruby is made with Rust.\n\nInvalid UTF-8: \xFF.\n\nSlash \\ and quote \" are escaped."#,
);

no_std

This crate is no_std compatible. This crate does not depend on alloc.

Structs

ByteSequenceTooLongError

Error that indicates a InvalidUtf8ByteSequence could not be constructed because the byte sequence contained more than three bytes.

InvalidUtf8ByteSequence

Iterator of Ruby debug escape sequences for a contiguous invalid UTF-8 byte sequence.

Literal

Iterator of Ruby debug escape sequences for a byte.

Functions

ascii_char_with_escape

Returns whether the given char has an ASCII literal escape code.

format_debug_escape_into

Write a UTF-8 debug representation of a byte slice into the given writer.