cat: unify handling of ANSI color spaces

Author: Alonely0

src/uu/cat/src/colors.rs

@@ -18,37 +18,21 @@ pub enum ColorMode {
 impl ColorMode {
     fn conv_color(&self, color: [f64; 3]) -> Color {
         let fit_linear_curve = |x: f64| (127. * x + 128.) as u8;
-
+        let retrofit_ansi = |color: [f64; 3]| {
+            let ratio = [36, 6, 1];
+            let ascii_color_offset = 16u16;
+            color
+                .into_iter()
+                .map(fit_linear_curve)
+                .zip(ratio)
+                .fold(ascii_color_offset, |acc, (c, m)| {
+                    acc + ((6. * (c as f64 / 256.)).floor() as u16) * m
+                })
+        };
         match self {
             ColorMode::TrueColor => Color::Color24b(color.map(fit_linear_curve)),
-            ColorMode::ANSI256 => {
-                let ratio = [36, 6, 1];
-                let ascii_color_offset = 16u16;
-
-                Color::ANSI256(
-                    color
-                        .into_iter()
-                        .map(fit_linear_curve)
-                        .zip(ratio)
-                        .fold(ascii_color_offset, |acc, (c, m)| {
-                            acc + ((6. * (c as f64 / 256.)).floor() as u16) * m
-                        }),
-                )
-            }
-            ColorMode::ANSI => {
-                let ratio = [32, 16, 14];
-                let ascii_color_offset = 91u8;
-
-                Color::ANSI(
-                    color
-                        .into_iter()
-                        .map(fit_linear_curve)
-                        .zip(ratio)
-                        .fold(ascii_color_offset, |acc, (c, m)| {
-                            acc + ((4. * (c as f64 / 256.)).floor() as u8) * m
-                        }),
-                )
-            }
+            ColorMode::ANSI256 => Color::ANSI256(retrofit_ansi(color)),
+            ColorMode::ANSI => Color::ANSI(retrofit_ansi(color) as u8),
         }
     }
 }