use crate::expression_tree::Expression;
pub fn parse_color_literal(str: &str) -> Option<u32> {
if !str.starts_with('#') {
return None;
}
if !str.is_ascii() {
return None;
}
let str = &str[1..];
let (r, g, b, a) = match str.len() {
3 => (
u8::from_str_radix(&str[0..=0], 16).ok()? * 0x11,
u8::from_str_radix(&str[1..=1], 16).ok()? * 0x11,
u8::from_str_radix(&str[2..=2], 16).ok()? * 0x11,
255u8,
),
4 => (
u8::from_str_radix(&str[0..=0], 16).ok()? * 0x11,
u8::from_str_radix(&str[1..=1], 16).ok()? * 0x11,
u8::from_str_radix(&str[2..=2], 16).ok()? * 0x11,
u8::from_str_radix(&str[3..=3], 16).ok()? * 0x11,
),
6 => (
u8::from_str_radix(&str[0..2], 16).ok()?,
u8::from_str_radix(&str[2..4], 16).ok()?,
u8::from_str_radix(&str[4..6], 16).ok()?,
255u8,
),
8 => (
u8::from_str_radix(&str[0..2], 16).ok()?,
u8::from_str_radix(&str[2..4], 16).ok()?,
u8::from_str_radix(&str[4..6], 16).ok()?,
u8::from_str_radix(&str[6..8], 16).ok()?,
),
_ => return None,
};
Some((a as u32) << 24 | (r as u32) << 16 | (g as u32) << 8 | (b as u32))
}
#[test]
fn test_parse_color_literal() {
assert_eq!(parse_color_literal("#abc"), Some(0xffaabbcc));
assert_eq!(parse_color_literal("#ABC"), Some(0xffaabbcc));
assert_eq!(parse_color_literal("#AbC"), Some(0xffaabbcc));
assert_eq!(parse_color_literal("#AbCd"), Some(0xddaabbcc));
assert_eq!(parse_color_literal("#01234567"), Some(0x67012345));
assert_eq!(parse_color_literal("#012345"), Some(0xff012345));
assert_eq!(parse_color_literal("_01234567"), None);
assert_eq!(parse_color_literal("→↓←"), None);
assert_eq!(parse_color_literal("#→↓←"), None);
assert_eq!(parse_color_literal("#1234567890"), None);
}
pub fn unescape_string(string: &str) -> Option<String> {
if string.contains('\n') {
return None;
}
let string = string.strip_prefix('"').or_else(|| string.strip_prefix('}'))?;
let string = string.strip_suffix('"').or_else(|| string.strip_suffix("\\{"))?;
if !string.contains('\\') {
return Some(string.into());
}
let mut result = String::with_capacity(string.len());
let mut pos = 0;
loop {
let stop = match string[pos..].find('\\') {
Some(stop) => pos + stop,
None => {
result += &string[pos..];
return Some(result);
}
};
if stop + 1 >= string.len() {
return None;
}
result += &string[pos..stop];
pos = stop + 2;
match string.as_bytes()[stop + 1] {
b'"' => result += "\"",
b'\\' => result += "\\",
b'n' => result += "\n",
b'u' => {
if string.as_bytes().get(pos)? != &b'{' {
return None;
}
let end = string[pos..].find('}')? + pos;
let x = u32::from_str_radix(&string[pos + 1..end], 16).ok()?;
result.push(std::char::from_u32(x)?);
pos = end + 1;
}
_ => return None,
}
}
}
#[test]
fn test_unescape_string() {
assert_eq!(unescape_string(r#""foo_bar""#), Some("foo_bar".into()));
assert_eq!(unescape_string(r#""foo\"bar""#), Some("foo\"bar".into()));
assert_eq!(unescape_string(r#""foo\\\"bar""#), Some("foo\\\"bar".into()));
assert_eq!(unescape_string(r#""fo\na\\r""#), Some("fo\na\\r".into()));
assert_eq!(unescape_string(r#""fo\xa""#), None);
assert_eq!(unescape_string(r#""fooo\""#), None);
assert_eq!(unescape_string(r#""f\n\n\nf""#), Some("f\n\n\nf".into()));
assert_eq!(unescape_string(r#""music\♪xx""#), None);
assert_eq!(unescape_string(r#""music\"♪\"🎝""#), Some("music\"♪\"🎝".into()));
assert_eq!(unescape_string(r#""foo_bar"#), None);
assert_eq!(unescape_string(r#""foo_bar\"#), None);
assert_eq!(unescape_string(r#"foo_bar""#), None);
assert_eq!(unescape_string(r#""d\u{8}a\u{d4}f\u{Ed3}""#), Some("d\u{8}a\u{d4}f\u{ED3}".into()));
assert_eq!(unescape_string(r#""xxx\""#), None);
assert_eq!(unescape_string(r#""xxx\u""#), None);
assert_eq!(unescape_string(r#""xxx\uxx""#), None);
assert_eq!(unescape_string(r#""xxx\u{""#), None);
assert_eq!(unescape_string(r#""xxx\u{22""#), None);
assert_eq!(unescape_string(r#""xxx\u{qsdf}""#), None);
assert_eq!(unescape_string(r#""xxx\u{1234567890}""#), None);
}
pub fn parse_number_literal(s: String) -> Result<Expression, String> {
let bytes = s.as_bytes();
let mut end = 0;
while end < bytes.len() && matches!(bytes[end], b'0'..=b'9' | b'.') {
end += 1;
}
let val = s[..end].parse().map_err(|_| "Cannot parse number literal".to_owned())?;
let unit = s[end..].parse().map_err(|_| "Invalid unit".to_owned())?;
Ok(Expression::NumberLiteral(val, unit))
}
#[test]
fn test_parse_number_literal() {
use crate::expression_tree::Unit;
fn doit(s: &str) -> Result<(f64, Unit), String> {
parse_number_literal(s.into()).map(|e| match e {
Expression::NumberLiteral(a, b) => (a, b),
_ => panic!(),
})
}
assert_eq!(doit("10"), Ok((10., Unit::None)));
assert_eq!(doit("10phx"), Ok((10., Unit::Phx)));
assert_eq!(doit("10.0phx"), Ok((10., Unit::Phx)));
assert_eq!(doit("10.0"), Ok((10., Unit::None)));
assert_eq!(doit("1.1phx"), Ok((1.1, Unit::Phx)));
assert_eq!(doit("10.10"), Ok((10.10, Unit::None)));
assert_eq!(doit("10000000"), Ok((10000000., Unit::None)));
assert_eq!(doit("10000001phx"), Ok((10000001., Unit::Phx)));
let wrong_unit = Err("Invalid unit".to_owned());
let cannot_parse = Err("Cannot parse number literal".to_owned());
assert_eq!(doit("10000001 phx"), wrong_unit);
assert_eq!(doit("12.10.12phx"), cannot_parse);
assert_eq!(doit("12.12oo"), wrong_unit);
assert_eq!(doit("12.12€"), wrong_unit);
}