Pull 2D turning into grid module

2019/11/src/main.rs

@@ -9,24 +9,6 @@ struct Robot {
 }
 
 impl Robot {
-    fn turn(&mut self, turn_value: i64) {
-        self.direction = match turn_value {
-            0 => match self.direction {
-                Direction::Up => Direction::Left,
-                Direction::Right => Direction::Up,
-                Direction::Down => Direction::Right,
-                Direction::Left => Direction::Down,
-            },
-            1 => match self.direction {
-                Direction::Up => Direction::Right,
-                Direction::Right => Direction::Down,
-                Direction::Down => Direction::Left,
-                Direction::Left => Direction::Up,
-            },
-            _ => unreachable!("Illegal turn value"),
-        }
-    }
-
     fn mov(&mut self) {
         self.position.mov(&self.direction);
     }
@@ -50,7 +32,7 @@ fn start_with_input(input: Vec<i64>, color: i64) -> Robot {
     while let IntComputerResult::Output(o) = pc.run() {
         robot.paint(o);
         let turn_int = pc.run().unwrap();
-        robot.turn(turn_int);
+        robot.direction.turn(turn_int * 2 - 1);
         robot.mov();
         pc.params.push(robot.current_color());
     }

2019/grid/src/lib.rs

@@ -10,6 +10,7 @@ pub struct Position2D {
     pub y: i64,
 }
 
+#[derive(Clone, Copy)]
 pub enum Direction {
     Up,
     Down,
@@ -53,6 +54,27 @@ pub fn draw_ascii<T: Display, S: BuildHasher>(
     )
 }
 
+impl Direction {
+    pub fn turn(&mut self, turn_value: i64) {
+        *self = match turn_value {
+            -1 => match self {
+                Direction::Up => Direction::Left,
+                Direction::Right => Direction::Up,
+                Direction::Down => Direction::Right,
+                Direction::Left => Direction::Down,
+            },
+            1 => match self {
+                Direction::Up => Direction::Right,
+                Direction::Right => Direction::Down,
+                Direction::Down => Direction::Left,
+                Direction::Left => Direction::Up,
+            },
+            0 => *self,
+            n => unreachable!(format!("Illegal turn value: {}", n)),
+        }
+    }
+}
+
 impl Position2D {
     pub fn mov(&mut self, dir: &Direction) {
         *self = *self
@@ -90,6 +112,3 @@ impl From<(i64, i64)> for Position2D {
         }
     }
 }
-
-#[cfg(test)]
-mod tests {}