Merge PR #2249: fix(formats): support 4/8-digit hex, space-separated rgb and hsl in parse_color

crates/formats/src/model.rs

@@ -1296,20 +1296,60 @@ impl ListCounter {
     }
 }
 
-/// Parse a CSS / HTML colour: `#rgb`, `#rrggbb`, `rgb(r,g,b)` or a basic name.
+fn hsl_to_rgb(h: f64, s: f64, l: f64) -> Rgb {
+    let h = (h / 360.0).rem_euclid(1.0);
+    let s = s.clamp(0.0, 1.0);
+    let l = l.clamp(0.0, 1.0);
+    if s == 0.0 {
+        let v = (l * 255.0).round().clamp(0.0, 255.0) as u8;
+        return Rgb(v, v, v);
+    }
+    let q = if l < 0.5 { l * (1.0 + s) } else { l + s - l * s };
+    let p = 2.0 * l - q;
+    let hue_to_rgb = |mut t: f64| -> f64 {
+        if t < 0.0 {
+            t += 1.0;
+        }
+        if t > 1.0 {
+            t -= 1.0;
+        }
+        if t < 1.0 / 6.0 {
+            return p + (q - p) * 6.0 * t;
+        }
+        if t < 1.0 / 2.0 {
+            return q;
+        }
+        if t < 2.0 / 3.0 {
+            return p + (q - p) * (2.0 / 3.0 - t) * 6.0;
+        }
+        p
+    };
+    let r = (hue_to_rgb(h + 1.0 / 3.0) * 255.0).round().clamp(0.0, 255.0) as u8;
+    let g = (hue_to_rgb(h) * 255.0).round().clamp(0.0, 255.0) as u8;
+    let b = (hue_to_rgb(h - 1.0 / 3.0) * 255.0).round().clamp(0.0, 255.0) as u8;
+    Rgb(r, g, b)
+}
+
+/// Parse a CSS / HTML colour: `#rgb`, `#rgba`, `#rrggbb`, `#rrggbbaa`, `rgb(...)`, `hsl(...)` or a basic name.
 pub fn parse_color(s: &str) -> Option<Rgb> {
     let s = s.trim().to_ascii_lowercase();
     if let Some(h) = s.strip_prefix('#') {
-        if h.len() == 3 && h.is_ascii() {
+        if (h.len() == 3 || h.len() == 4) && h.is_ascii() {
             let d = |i: usize| h.get(i..i + 1).and_then(|x| u8::from_str_radix(x, 16).ok()).map(|v| v * 17);
             return Some(Rgb(d(0)?, d(1)?, d(2)?));
         }
+        if h.len() == 8 && h.is_ascii() {
+            let p = |i: usize| h.get(i..i + 2).and_then(|x| u8::from_str_radix(x, 16).ok());
+            return Some(Rgb(p(0)?, p(2)?, p(4)?));
+        }
         return Rgb::parse(h);
     }
     if let Some(inner) = s.strip_prefix("rgb(").or_else(|| s.strip_prefix("rgba(")) {
-        let v: Vec<u8> = inner
-            .trim_end_matches(')')
-            .split(',')
+        let inner = inner.trim_end_matches(')').trim();
+        let before_slash = inner.split('/').next().unwrap_or(inner);
+        let parts: Vec<&str> = if before_slash.contains(',') { before_slash.split(',').collect() } else { before_slash.split_whitespace().collect() };
+        let v: Vec<u8> = parts
+            .iter()
             .take(3)
             .filter_map(|x| {
                 let x = x.trim();
@@ -1325,6 +1365,35 @@ pub fn parse_color(s: &str) -> Option<Rgb> {
         }
         return None;
     }
+    if let Some(inner) = s.strip_prefix("hsl(").or_else(|| s.strip_prefix("hsla(")) {
+        let inner = inner.trim_end_matches(')').trim();
+        let before_slash = inner.split('/').next().unwrap_or(inner);
+        let parts: Vec<&str> = if before_slash.contains(',') { before_slash.split(',').collect() } else { before_slash.split_whitespace().collect() };
+        if parts.len() < 3 {
+            return None;
+        }
+        let h_str = parts[0].trim();
+        let h: f64 = if let Some(deg) = h_str.strip_suffix("deg") {
+            deg.trim().parse().ok()?
+        } else if let Some(rad) = h_str.strip_suffix("rad") {
+            rad.trim().parse::<f64>().ok()? * 180.0 / std::f64::consts::PI
+        } else if let Some(turn) = h_str.strip_suffix("turn") {
+            turn.trim().parse::<f64>().ok()? * 360.0
+        } else {
+            h_str.parse().ok()?
+        };
+        let parse_pct = |x: &str| -> Option<f64> {
+            let x = x.trim();
+            if let Some(p) = x.strip_suffix('%') {
+                Some((p.trim().parse::<f64>().ok()? / 100.0).clamp(0.0, 1.0))
+            } else {
+                Some(x.parse::<f64>().ok()?.clamp(0.0, 1.0))
+            }
+        };
+        let s = parse_pct(parts[1])?;
+        let l = parse_pct(parts[2])?;
+        return Some(hsl_to_rgb(h, s, l));
+    }
     Some(match s.as_str() {
         "black" => Rgb(0, 0, 0),
         "white" => Rgb(255, 255, 255),
@@ -1375,8 +1444,15 @@ mod tests {
     #[test]
     fn colors() {
         assert_eq!(parse_color("#f00"), Some(Rgb(255, 0, 0)));
+        assert_eq!(parse_color("#f00f"), Some(Rgb(255, 0, 0)));
         assert_eq!(parse_color("#0080FF"), Some(Rgb(0, 128, 255)));
+        assert_eq!(parse_color("#0080ff80"), Some(Rgb(0, 128, 255)));
         assert_eq!(parse_color("rgb(1, 2, 3)"), Some(Rgb(1, 2, 3)));
+        assert_eq!(parse_color("rgb(1 2 3)"), Some(Rgb(1, 2, 3)));
+        assert_eq!(parse_color("rgb(1 2 3 / 50%)"), Some(Rgb(1, 2, 3)));
+        assert_eq!(parse_color("hsl(0, 100%, 50%)"), Some(Rgb(255, 0, 0)));
+        assert_eq!(parse_color("hsl(120deg 100% 50%)"), Some(Rgb(0, 255, 0)));
+        assert_eq!(parse_color("hsla(240, 100%, 50%, 0.8)"), Some(Rgb(0, 0, 255)));
         assert_eq!(parse_color("navy"), Some(Rgb(0, 0, 128)));
         assert_eq!(parse_color("#zz"), None);
         assert_eq!(parse_color("rgb(1)"), None);