From 1221df26342158b244c2c4108ffb2d22dff8227e Mon Sep 17 00:00:00 2001
From: Max Bradbury <max@tinybird.info>
Date: Sun, 12 Apr 2020 10:06:08 +0100
Subject: [PATCH] implement ToString for colour; test for palette to string

---
 src/main.rs | 30 ++++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 2791b2d..4b11c55 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -594,14 +594,17 @@ fn test_colour_from_string() {
     );
 }
 
-fn colour_to_string(colour: Colour) -> String {
-    format!("{},{},{}", colour.red, colour.green, colour.blue)
+impl ToString for Colour {
+    #[inline]
+    fn to_string(&self) -> String {
+        format!("{},{},{}", self.red, self.green, self.blue)
+    }
 }
 
 #[test]
 fn test_colour_to_string() {
     assert_eq!(
-        colour_to_string(Colour { red: 22, green: 33, blue: 44 }),
+        Colour { red: 22, green: 33, blue: 44 }.to_string(),
         "22,33,44".to_string()
     );
 }
@@ -670,14 +673,29 @@ fn palette_to_string(palette: Palette) -> String {
         "".to_string()
     };
 
-    let colours: Vec<String> = palette.colours.into_iter().map(|colour| {
-        colour_to_string(colour)
-    }).collect();
+    let colours: Vec<String> = palette.colours.into_iter().map(|colour|
+        colour.to_string()
+    ).collect();
     let colours = colours.join("\n");
 
     format!("PAL {}\n{}{}", palette.id, name, colours)
 }
 
+#[test]
+fn test_palette_to_string() {
+    let output = palette_to_string(Palette {
+        id: "g".to_string(),
+        name: Some("moss".to_string()),
+        colours: vec![
+            Colour {red: 1,   green: 2,   blue: 3  },
+            Colour {red: 255, green: 254, blue: 253},
+            Colour {red: 126, green: 127, blue: 128},
+        ]
+    });
+    let expected = "PAL g\nNAME moss\n1,2,3\n255,254,253\n126,127,128".to_string();
+    assert_eq!(output, expected);
+}
+
 fn position_from_string(string: String) -> Position {
     // e.g. "2,5"
     let xy: Vec<&str> = string.split(',').collect();