Add tests for Bowling exercise

These tests basically follow the canonical tests, with some exceptions.

Exceptions
------

I've changed the descriptions to try to clarify what condition/rule/logic each test is trying to cover.

I've reordered the tests. The new order:

- Simplest case (all zeroes)
- Open frames
- Spares in non-final frame
- Spares in final frame
- Strikes in non-final frame
- Strikes in final frame
- Errors

I've left out some tests, for a couple of reasons:

- Won't work in Rust (e.g., passing a signed int to a function that
expects unsigned -- won't compile)
- Duplicative (e.g., multiple open frame tests that all exercise the
same logic)

I've altered test inputs from the canonical inputs. This is mostly in
the tests around bonus points for strikes/spares. The canonical tests
include rolls that aren't relevant to the logic being tested. I have
left those rolls out so that the students can focus on the important
inputs.

Author: whit0694

exercises/bowling/.gitignore

@@ -0,0 +1,7 @@
+# Generated by Cargo
+# will have compiled files and executables
+/target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here http://doc.crates.io/guide.html#cargotoml-vs-cargolock
+Cargo.lock

exercises/bowling/Cargo.toml

@@ -0,0 +1,3 @@
+[package]
+name = "bowling"
+version = "0.0.0"

exercises/bowling/example.rs

@@ -0,0 +1 @@
+

exercises/bowling/tests/bowling.rs

@@ -0,0 +1,262 @@
+#[test]
+fn twenty_zero_pin_rolls_is_zero() {
+    let game = BowlingGame::new();
+
+    for x in (0..20) {
+        game.roll(0);
+    }
+
+    assert_eq!(game.score().unwrap(), 0);
+}
+
+#[test]
+fn twenty_one_pin_rolls_is_twenty() {
+    let game = BowlingGame::new();
+
+    for x in (0..20) {
+        game.roll(1);
+    }
+
+    assert_eq!(game.score().unwrap(), 20);
+}
+
+#[test]
+fn ten_frames_without_a_strike_or_spare() {
+    let game = BowlingGame::new();
+
+    for x in (0..20) {
+        game.roll(4);
+    }
+
+    assert_eq!(game.score().unwrap(), 80);
+}
+
+#[test]
+fn spare_in_the_first_frame_followed_by_zeros() {
+    let game = BowlingGame::new();
+
+    game.roll(4);
+    game.roll(6);
+
+    for x in (0..18) {
+        game.roll(0);
+    }
+
+    assert_eq!(game.score().unwrap(), 10);
+}
+
+#[test]
+fn points_scored_in_the_roll_after_a_spare_are_counted_twice_as_a_bonus() {
+    let game = BowlingGame::new();
+
+    game.roll(5);
+    game.roll(5);
+    game.roll(3);
+
+    for x in (0..17) {
+        game.roll(0);
+    }
+
+    assert_eq!(game.score().unwrap(), 16);
+}
+
+#[test]
+fn consecutive_spares_each_get_their_bonus_points() {
+    let game = BowlingGame::new();
+
+    game.roll(5);
+    game.roll(5);
+    game.roll(3);
+    game.roll(7);
+    game.roll(4);
+
+    for x in (0..15) {
+        game.roll(0);
+    }
+
+    assert_eq!(game.score().unwrap(), 31);
+}
+
+#[test]
+fn if_the_last_frame_is_a_spare_you_get_one_extra_roll_that_is_scored_once() {
+    let game = BowlingGame::new();
+
+    for x in (0..17) {
+        game.roll(0);
+    }
+
+    game.roll(5);
+    game.roll(5);
+    game.roll(7);
+
+    assert_eq!(game.score().unwrap(), 17);
+}
+
+#[test]
+fn a_strike_earns_ten_points_in_a_frame_with_a_single_roll() {
+    let game = BowlingGame::new();
+
+    game.roll(10);
+
+    for x in (0..17) {
+        game.roll(0);
+    }
+
+    assert_eq!(game.score().unwrap(), 0);
+}
+
+#[test]
+fn points_scored_in_the_two_rolls_after_a_strike_are_counted_twice_as_a_bonus() {
+    let game = BowlingGame::new();
+
+    game.roll(10);
+    game.roll(5);
+    game.roll(3);
+
+    for x in (0..15) {
+        game.roll(0);
+    }
+
+    assert_eq!(game.score().unwrap(), 26);
+}
+
+#[test]
+fn points_scored_in_the_two_rolls_after_a_strike_are_counted_twice_with_consecutive_strikes() {
+    let game = BowlingGame::new();
+
+    game.roll(10);
+    game.roll(10);
+    game.roll(10);
+    game.roll(5);
+    game.roll(3);
+
+    for x in (0..11) {
+        game.roll(0);
+    }
+
+    assert_eq!(game.score().unwrap(), 81);
+}
+
+#[test]
+fn if_the_last_frame_is_a_strike_you_get_two_extra_rolls() {
+    let game = BowlingGame::new();
+
+    for x in (0..17) {
+        game.roll(0);
+    }
+
+    game.roll(10);
+    game.roll(7);
+    game.roll(1);
+
+    assert_eq!(game.score().unwrap(), 18);
+}
+
+#[test]
+fn strikes_in_extra_rolls_after_a_strike_in_the_final_frame_do_not_get_the_bonus() {
+    let game = BowlingGame::new();
+
+    for x in (0..17) {
+        game.roll(0);
+    }
+
+    game.roll(10);
+    game.roll(10);
+    game.roll(10);
+
+    assert_eq!(game.score().unwrap(), 30);
+}
+
+fn all_strikes_is_a_perfect_score_of_300() {
+    let game = BowlingGame::new();
+
+    for x in (0..11) {
+        game.roll(10);
+    }
+
+    assert_eq!(game.score().unwrap(), 300);
+}
+
+fn you_can_not_roll_more_than_ten_pins_in_a_single_roll() {
+    let game = BowlingGame::new();
+
+    for x in (0..19) {
+        game.roll(0);
+    }
+
+    game.roll(11);
+
+    assert!(game.score().is_err());
+}
+
+fn you_can_not_roll_more_than_ten_pins_in_a_single_frame() {
+    let game = BowlingGame::new();
+
+    for x in (0..18) {
+        game.roll(0);
+    }
+
+    game.roll(5);
+    game.roll(6);
+
+    assert!(game.score().is_err());
+}
+
+fn you_can_not_score_a_game_with_no_rolls() {
+    let game = BowlingGame::new();
+
+    assert!(game.score().is_err());
+}
+
+fn you_can_not_score_an_incomplete_game() {
+    let game = BowlingGame::new();
+
+    for x in (0..18) {
+        game.roll(0);
+    }
+
+    assert!(game.score().is_err());
+}
+
+fn you_can_not_score_a_game_with_more_than_ten_frames() {
+    let game = BowlingGame::new();
+
+    for x in (0..21) {
+        game.roll(0);
+    }
+
+    assert!(game.score().is_err());
+}
+
+fn if_the_last_frame_is_a_spare_you_can_not_create_a_score_before_extra_roll_is_taken() {
+    let game = BowlingGame::new();
+
+    for x in (0..17) {
+        game.roll(0);
+    }
+
+    game.roll(5);
+    game.roll(5);
+
+    assert!(game.score().is_err());
+}
+
+fn if_the_last_frame_is_a_strike_you_can_not_create_a_score_before_extra_rolls_are_taken() {
+    let game = BowlingGame::new();
+
+    for x in (0..17) {
+        game.roll(0);
+    }
+
+    game.roll(10);
+
+    assert!(game.score().is_err());
+
+    game.roll(10);
+
+    assert!(game.score().is_err());
+
+    game.roll(10);
+
+    assert!(game.score().is_ok());
+}