Add #rrggbb string parsing

src/lib.rs

@@ -1799,8 +1799,35 @@ impl ColorSpec {
 /// 2. A single 8-bit integer, in either decimal or hexadecimal format.
 /// 3. A triple of 8-bit integers separated by a comma, where each integer is
 ///    in decimal or hexadecimal format.
+/// 4. A `#` followed by 6 hexadecimal digits of any case, with each octet
+///    representing red, green and blue, respectively.
 ///
 /// Hexadecimal numbers are written with a `0x` prefix.
+///
+/// ## Example
+/// ```
+/// use termcolor::Color;
+///
+/// let color = "red".parse::<Color>();
+/// assert_eq!(color, Ok(Color::Red));
+///
+/// let color = "32".parse::<Color>();
+/// assert_eq!(color, Ok(Color::Ansi256(32)));
+///
+/// // Note that also lowercase 0xaa is allowed
+/// let color = "0xAA".parse::<Color>();
+/// assert_eq!(color, Ok(Color::Ansi256(0xAA)));
+///
+/// let color = "0,128,255".parse::<Color>();
+/// assert_eq!(color, Ok(Color::Rgb(0, 128, 255)));
+///
+/// let color = "0x0,0xFF,0x0".parse::<Color>();
+/// assert_eq!(color, Ok(Color::Rgb(0, 0xFF, 0)));
+///
+/// // Note that also lowercase #ff6633 is allowed
+/// let color = "#FF6633".parse::<Color>();
+/// assert_eq!(color, Ok(Color::Rgb(0xFF, 0x66, 0x33)));
+/// ```
 #[allow(missing_docs)]
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub enum Color {
@@ -1866,7 +1893,8 @@ impl Color {
         // corresponding to one of 256 colors.
         //
         // The "rgb" format is a triple of numbers (decimal or hex) delimited
-        // by a comma corresponding to one of 256^3 colors.
+        // by a comma corresponding to one of 256^3 colors or #rrggbb string
+        // in the hex format.
 
         fn parse_number(s: &str) -> Option<u8> {
             use std::u8;
@@ -1880,7 +1908,22 @@ impl Color {
 
         let codes: Vec<&str> = s.split(',').collect();
         if codes.len() == 1 {
-            if let Some(n) = parse_number(&codes[0]) {
+            if codes[0].starts_with('#') {
+                use std::u8;
+                if codes[0].len() == 7 {
+                    if let (Ok(r), Ok(g), Ok(b)) = (
+                        u8::from_str_radix(&codes[0][1..3], 16),
+                        u8::from_str_radix(&codes[0][3..5], 16),
+                        u8::from_str_radix(&codes[0][5..7], 16),
+                    ) {
+                        return Ok(Color::Rgb(r, g, b));
+                    }
+                }
+                Err(ParseColorError {
+                    kind: ParseColorErrorKind::InvalidRgb,
+                    given: s.to_string(),
+                })
+            } else if let Some(n) = parse_number(&codes[0]) {
                 Ok(Color::Ansi256(n))
             } else {
                 if s.chars().all(|c| c.is_digit(16)) {
@@ -2137,6 +2180,18 @@ mod tests {
 
         let color = "0x33,0x66,0xFF".parse::<Color>();
         assert_eq!(color, Ok(Color::Rgb(0x33, 0x66, 0xFF)));
+
+        let color = "0xCC,0xaa,0xff".parse::<Color>();
+        assert_eq!(color, Ok(Color::Rgb(0xCC, 0xAA, 0xFF)));
+
+        let color = "0xCC,0xaa,0xff".parse::<Color>();
+        assert_eq!(color, Ok(Color::Rgb(0xCC, 0xAA, 0xFF)));
+
+        let color = "#FF6633".parse::<Color>();
+        assert_eq!(color, Ok(Color::Rgb(0xFF, 0x66, 0x33)));
+
+        let color = "#ffCCaa".parse::<Color>();
+        assert_eq!(color, Ok(Color::Rgb(0xFF, 0xCC, 0xAA)));
     }
 
     #[test]
@@ -2149,6 +2204,15 @@ mod tests {
                 given: "0,0,256".to_string(),
             })
         );
+
+        let color = "0,0,aaa".parse::<Color>();
+        assert_eq!(
+            color,
+            Err(ParseColorError {
+                kind: ParseColorErrorKind::InvalidRgb,
+                given: "0,0,aaa".to_string(),
+            })
+        );
     }
 
     #[test]
@@ -2162,6 +2226,24 @@ mod tests {
             })
         );
 
+        let color = "#ffCC001".parse::<Color>();
+        assert_eq!(
+            color,
+            Err(ParseColorError {
+                kind: ParseColorErrorKind::InvalidRgb,
+                given: "#ffCC001".to_string()
+            })
+        );
+
+        let color = "#00CC1".parse::<Color>();
+        assert_eq!(
+            color,
+            Err(ParseColorError {
+                kind: ParseColorErrorKind::InvalidRgb,
+                given: "#00CC1".to_string()
+            })
+        );
+
         let color = "not_a_color".parse::<Color>();
         assert_eq!(
             color,
@@ -2170,6 +2252,24 @@ mod tests {
                 given: "not_a_color".to_string(),
             })
         );
+
+        let color = "#00ggee".parse::<Color>();
+        assert_eq!(
+            color,
+            Err(ParseColorError {
+                kind: ParseColorErrorKind::InvalidRgb,
+                given: "#00ggee".to_string(),
+            })
+        );
+
+        let color = "#00gg😜".parse::<Color>();
+        assert_eq!(
+            color,
+            Err(ParseColorError {
+                kind: ParseColorErrorKind::InvalidRgb,
+                given: "#00gg😜".to_string(),
+            })
+        );
     }
 
     #[test]