Add the Display trait implementation to allow rendering

1 files changed, 69 insertions, 1 deletions

diff --git a/CLI/rust/src/game_of_life/simulation/universe.rs b/CLI/rust/src/game_of_life/simulation/universe.rs
index 69d8f67..dab1915 100644
--- a/CLI/rust/src/game_of_life/simulation/universe.rs
+++ b/CLI/rust/src/game_of_life/simulation/universe.rs
@@ -1,7 +1,7 @@
 use super::circular_index;
 use crate::game_of_life::opts::Opts;
 use crate::game_of_life::simulation::plane::Plane;
-use std::ops::Index;
+use std::{fmt, ops::Index};
 
 /// Game of Life universe struct for running simulations
 #[derive(Debug, Clone, PartialEq)]
@@ -11,6 +11,74 @@ pub(crate) struct Universe {
     pub future: Plane<Plane<bool>>,
 }
 
+/// Implement print for the universe
+impl fmt::Display for Universe {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let mut to_s = String::new();
+        for row in 0..self.current.len() {
+            for col in 0..self.current[row].len() {
+                match self[row as isize][col as isize] {
+                    true => to_s.push(self.opts.live_cell),
+                    false => to_s.push(self.opts.dead_cell),
+                };
+            }
+            to_s.push_str("\n");
+        }
+        to_s.push_str(&format!("{}", self.opts.banner()));
+        write!(f, "{}", to_s)
+    }
+}
+
+#[cfg(test)]
+mod display {
+    use super::*;
+
+    fn universe(opts: Opts) -> Universe {
+        Universe {
+            opts,
+            current: Plane(vec![
+                Plane(vec![false; 5]),
+                Plane(vec![false, true, true, true, false]),
+                Plane(vec![false; 5]),
+            ]),
+            future: Plane(vec![Plane(vec![])]),
+        }
+    }
+
+    #[test]
+    fn without_input() {
+        let opts = Opts {
+            input: None,
+            seed: 1337,
+            width: 13,
+            height: 13,
+            live_cell: 'L',
+            dead_cell: 'D',
+            delay: 13,
+        };
+
+        let universe = universe(opts);
+        assert_eq!(universe.to_string(), "DDDDD\nDLLLD\nDDDDD\nSeed: 1337")
+    }
+
+    #[test]
+    fn with_input() {
+        let opts = Opts {
+            input: Some(String::from("http://example.com")),
+            seed: 1337,
+            width: 13,
+            height: 13,
+            live_cell: 'X',
+            dead_cell: '.',
+            delay: 13,
+        };
+
+        let universe = universe(opts);
+        assert_eq!(universe.to_string(), ".....\n.XXX.\n.....\nInput: http://example.com")
+    }
+
+}
+
 impl Index<isize> for Universe {
     type Output = Plane<bool>;
     fn index(&self, idx: isize) -> &Plane<bool> {