feature: support 3-char hex colours (#1022)

1 files changed, 124 insertions, 48 deletions

diff --git a/src/canvas/canvas_styling/colour_utils.rs b/src/canvas/canvas_styling/colour_utils.rs
index 89b1b170..2814c580 100644
--- a/src/canvas/canvas_styling/colour_utils.rs
+++ b/src/canvas/canvas_styling/colour_utils.rs
@@ -1,4 +1,7 @@
+use concat_string::concat_string;
+use itertools::Itertools;
 use tui::style::{Color, Style};
+use unicode_segmentation::UnicodeSegmentation;
 
 use crate::utils::error;
 
@@ -10,41 +13,44 @@ pub const HIGHLIGHT_COLOUR: Color = Color::LightBlue;
 pub const AVG_COLOUR: Color = Color::Red;
 pub const ALL_COLOUR: Color = Color::Green;
 
+/// Convert a hex string to a colour.
 fn convert_hex_to_color(hex: &str) -> error::Result<Color> {
-    fn hex_err(hex: &str) -> error::Result<u8> {
-        Err(
+    fn hex_component_to_int(hex: &str, first: &str, second: &str) -> error::Result<u8> {
+        u8::from_str_radix(&concat_string!(first, second), 16).map_err(|_| {
             error::BottomError::ConfigError(format!(
-                "\"{}\" is an invalid hex colour.  It must be a valid 7 character hex string of the (ie: \"#112233\")."
-            , hex))
-        )
+                "\"{hex}\" is an invalid hex color, could not decode."
+            ))
+        })
     }
 
-    fn convert_hex_to_rgb(hex: &str) -> error::Result<(u8, u8, u8)> {
-        let hex_components: Vec<char> = hex.chars().collect();
+    fn invalid_hex_format(hex: &str) -> error::BottomError {
+        error::BottomError::ConfigError(format!(
+            "\"{hex}\" is an invalid hex color. It must be either a 7 character hex string of the form \"#12ab3c\" or a 3 character hex string of the form \"#1a2\".",
+        ))
+    }
 
-        if hex_components.len() == 7 {
-            let mut r_string = hex_components[1].to_string();
-            r_string.push(hex_components[2]);
-            let mut g_string = hex_components[3].to_string();
-            g_string.push(hex_components[4]);
-            let mut b_string = hex_components[5].to_string();
-            b_string.push(hex_components[6]);
+    if !hex.starts_with('#') {
+        return Err(invalid_hex_format(hex));
+    }
 
-            let r = u8::from_str_radix(&r_string, 16).or_else(|_err| hex_err(hex))?;
-            let g = u8::from_str_radix(&g_string, 16).or_else(|_err| hex_err(hex))?;
-            let b = u8::from_str_radix(&b_string, 16).or_else(|_err| hex_err(hex))?;
+    let components = hex.graphemes(true).collect_vec();
+    if components.len() == 7 {
+        // A 6-long hex.
+        let r = hex_component_to_int(hex, components[1], components[2])?;
+        let g = hex_component_to_int(hex, components[3], components[4])?;
+        let b = hex_component_to_int(hex, components[5], components[6])?;
 
-            return Ok((r, g, b));
-        }
+        Ok(Color::Rgb(r, g, b))
+    } else if components.len() == 4 {
+        // A 3-long hex.
+        let r = hex_component_to_int(hex, components[1], components[1])?;
+        let g = hex_component_to_int(hex, components[2], components[2])?;
+        let b = hex_component_to_int(hex, components[3], components[3])?;
 
-        Err(error::BottomError::ConfigError(format!(
-            "\"{}\" is an invalid hex colour.  It must be a 7 character string of the form \"#112233\".",
-            hex
-        )))
+        Ok(Color::Rgb(r, g, b))
+    } else {
+        Err(invalid_hex_format(hex))
     }
-
-    let rgb = convert_hex_to_rgb(hex)?;
-    Ok(Color::Rgb(rgb.0, rgb.1, rgb.2))
 }
 
 pub fn str_to_fg(input_val: &str) -> error::Result<Style> {
@@ -58,7 +64,7 @@ pub fn str_to_colour(input_val: &str) -> error::Result<Color> {
         } else if input_val.contains(',') {
             convert_rgb_to_color(input_val)
         } else {
-            convert_name_to_color(input_val)
+            convert_name_to_colour(input_val)
         }
     } else {
         Err(error::BottomError::ConfigError(format!(
@@ -72,7 +78,7 @@ fn convert_rgb_to_color(rgb_str: &str) -> error::Result<Color> {
     let rgb_list = rgb_str.split(',').collect::<Vec<&str>>();
     if rgb_list.len() != 3 {
         return Err(error::BottomError::ConfigError(format!(
-            "value \"{}\" is an invalid RGB colour.  It must be a comma separated value with 3 integers from 0 to 255 (ie: \"255, 0, 155\").",
+            "value \"{}\" is an invalid RGB colour. It must be a comma separated value with 3 integers from 0 to 255 (ie: \"255, 0, 155\").",
             rgb_str
         )));
     }
@@ -91,13 +97,13 @@ fn convert_rgb_to_color(rgb_str: &str) -> error::Result<Color> {
         Ok(Color::Rgb(rgb[0], rgb[1], rgb[2]))
     } else {
         Err(error::BottomError::ConfigError(format!(
-            "value \"{}\" contained invalid RGB values.  It must be a comma separated value with 3 integers from 0 to 255 (ie: \"255, 0, 155\").",
+            "value \"{}\" contained invalid RGB values. It must be a comma separated value with 3 integers from 0 to 255 (ie: \"255, 0, 155\").",
             rgb_str
         )))
     }
 }
 
-fn convert_name_to_color(color_name: &str) -> error::Result<Color> {
+fn convert_name_to_colour(color_name: &str) -> error::Result<Color> {
     match color_name.to_lowercase().trim() {
         "reset" => Ok(Color::Reset),
         "black" => Ok(Color::Black),
@@ -117,7 +123,7 @@ fn convert_name_to_color(color_name: &str) -> error::Result<Color> {
         "lightcyan" | "light cyan" => Ok(Color::LightCyan),
         "white" => Ok(Color::White),
         _ => Err(error::BottomError::ConfigError(format!(
-            "\"{}\" is an invalid named colour.
+            "\"{}\" is an invalid named color.
             
 The following are supported strings: 
 +--------+-------------+---------------------+
@@ -144,49 +150,119 @@ mod test {
     use super::*;
 
     #[test]
-    fn test_invalid_colours() {
+    fn invalid_colour_names() {
         // Test invalid spacing in single word.
-        assert!(convert_name_to_color("bl ack").is_err());
+        assert!(convert_name_to_colour("bl ack").is_err());
 
         // Test invalid spacing in dual word.
-        assert!(convert_name_to_color("darkg ray").is_err());
+        assert!(convert_name_to_colour("darkg ray").is_err());
 
         // Test completely invalid colour.
-        assert!(convert_name_to_color("darkreset").is_err());
+        assert!(convert_name_to_colour("darkreset").is_err());
     }
 
     #[test]
-    fn test_valid_colours() {
+    fn valid_colour_names() {
         // Standard color should work
-        assert_eq!(convert_name_to_color("red"), Ok(Color::Red));
+        assert_eq!(convert_name_to_colour("red"), Ok(Color::Red));
 
         // Capitalizing should be fine.
-        assert_eq!(convert_name_to_color("RED"), Ok(Color::Red));
+        assert_eq!(convert_name_to_colour("RED"), Ok(Color::Red));
 
         // Spacing shouldn't be an issue now.
-        assert_eq!(convert_name_to_color(" red "), Ok(Color::Red));
+        assert_eq!(convert_name_to_colour(" red "), Ok(Color::Red));
 
         // The following are all equivalent.
-        assert_eq!(convert_name_to_color("darkgray"), Ok(Color::DarkGray));
-        assert_eq!(convert_name_to_color("darkgrey"), Ok(Color::DarkGray));
-        assert_eq!(convert_name_to_color("dark grey"), Ok(Color::DarkGray));
-        assert_eq!(convert_name_to_color("dark gray"), Ok(Color::DarkGray));
+        assert_eq!(convert_name_to_colour("darkgray"), Ok(Color::DarkGray));
+        assert_eq!(convert_name_to_colour("darkgrey"), Ok(Color::DarkGray));
+        assert_eq!(convert_name_to_colour("dark grey"), Ok(Color::DarkGray));
+        assert_eq!(convert_name_to_colour("dark gray"), Ok(Color::DarkGray));
 
-        assert_eq!(convert_name_to_color("grey"), Ok(Color::Gray));
-        assert_eq!(convert_name_to_color("gray"), Ok(Color::Gray));
+        assert_eq!(convert_name_to_colour("grey"), Ok(Color::Gray));
+        assert_eq!(convert_name_to_colour("gray"), Ok(Color::Gray));
 
         // One more test with spacing.
         assert_eq!(
-            convert_name_to_color(" lightmagenta "),
+            convert_name_to_colour(" lightmagenta "),
             Ok(Color::LightMagenta)
         );
         assert_eq!(
-            convert_name_to_color("light magenta"),
+            convert_name_to_colour("light magenta"),
             Ok(Color::LightMagenta)
         );
         assert_eq!(
-            convert_name_to_color(" light magenta "),
+            convert_name_to_colour(" light magenta "),
             Ok(Color::LightMagenta)
         );
     }
+
+    #[test]
+    fn valid_hex_colours() {
+        assert_eq!(
+            convert_hex_to_color("#ffffff").unwrap(),
+            Color::Rgb(255, 255, 255)
+        );
+        assert_eq!(
+            convert_hex_to_color("#000000").unwrap(),
+            Color::Rgb(0, 0, 0)
+        );
+        convert_hex_to_color("#111111").unwrap();
+        convert_hex_to_color("#11ff11").unwrap();
+        convert_hex_to_color("#1f1f1f").unwrap();
+        assert_eq!(
+            convert_hex_to_color("#123abc").unwrap(),
+            Color::Rgb(18, 58, 188)
+        );
+
+        assert_eq!(
+            convert_hex_to_color("#fff").unwrap(),
+            Color::Rgb(255, 255, 255)
+        );
+        assert_eq!(convert_hex_to_color("#000").unwrap(), Color::Rgb(0, 0, 0));
+        convert_hex_to_color("#111").unwrap();
+        convert_hex_to_color("#1f1").unwrap();
+        convert_hex_to_color("#f1f").unwrap();
+        convert_hex_to_color("#ff1").unwrap();
+        convert_hex_to_color("#1ab").unwrap();
+        assert_eq!(
+            convert_hex_to_color("#1ab").unwrap(),
+            Color::Rgb(17, 170, 187)
+        );
+    }
+
+    #[test]
+    fn invalid_hex_colours() {
+        assert!(convert_hex_to_color("ffffff").is_err());
+        assert!(convert_hex_to_color("111111").is_err());
+
+        assert!(convert_hex_to_color("fff").is_err());
+        assert!(convert_hex_to_color("111").is_err());
+        assert!(convert_hex_to_color("fffffff").is_err());
+        assert!(convert_hex_to_color("1234567").is_err());
+
+        assert!(convert_hex_to_color("#fffffff").is_err());
+        assert!(convert_hex_to_color("#1234567").is_err());
+        assert!(convert_hex_to_color("#ff").is_err());
+        assert!(convert_hex_to_color("#12").is_err());
+        assert!(convert_hex_to_color("").is_err());
+
+        assert!(convert_hex_to_color("#pppppp").is_err());
+        assert!(convert_hex_to_color("#00000p").is_err());
+        assert!(convert_hex_to_color("#ppp").is_err());
+
+        assert!(convert_hex_to_color("#一").is_err());
+        assert!(convert_hex_to_color("#一二").is_err());
+        assert!(convert_hex_to_color("#一二三").is_err());
+        assert!(convert_hex_to_color("#一二三四").is_err());
+
+        assert!(convert_hex_to_color("#f一f").is_err());
+        assert!(convert_hex_to_color("#ff一11").is_err());
+
+        assert!(convert_hex_to_color("#🇨🇦").is_err());
+        assert!(convert_hex_to_color("#🇨🇦🇨🇦").is_err());
+        assert!(convert_hex_to_color("#🇨🇦🇨🇦🇨🇦").is_err());
+        assert!(convert_hex_to_color("#🇨🇦🇨🇦🇨🇦🇨🇦").is_err());
+
+        assert!(convert_hex_to_color("#हिन्दी").is_err());
+    }
 }