6 files changed, 617 insertions, 0 deletions

diff --git a/rust/bowling/.exercism/metadata.json b/rust/bowling/.exercism/metadata.json
new file mode 100644
index 0000000..832eced
--- /dev/null
+++ b/rust/bowling/.exercism/metadata.json
@@ -0,0 +1 @@
+{"track":"rust","exercise":"bowling","id":"b330b3979d1e4e18ab421b2a06d22671","url":"https://exercism.io/my/solutions/b330b3979d1e4e18ab421b2a06d22671","handle":"dyamon","is_requester":true,"auto_approve":false}
\ No newline at end of file
diff --git a/rust/bowling/.gitignore b/rust/bowling/.gitignore
new file mode 100644
index 0000000..db7f315
--- /dev/null
+++ b/rust/bowling/.gitignore
@@ -0,0 +1,8 @@
+# Generated by Cargo
+# will have compiled files and executables
+/target/
+**/*.rs.bk
+
+# 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
diff --git a/rust/bowling/Cargo.toml b/rust/bowling/Cargo.toml
new file mode 100644
index 0000000..b14350e
--- /dev/null
+++ b/rust/bowling/Cargo.toml
@@ -0,0 +1,4 @@
+[package]
+edition = "2018"
+name = "bowling"
+version = "1.2.0"
diff --git a/rust/bowling/README.md b/rust/bowling/README.md
new file mode 100644
index 0000000..6c08b38
--- /dev/null
+++ b/rust/bowling/README.md
@@ -0,0 +1,141 @@
+# Bowling
+
+Score a bowling game.
+
+Bowling is a game where players roll a heavy ball to knock down pins
+arranged in a triangle. Write code to keep track of the score
+of a game of bowling.
+
+## Scoring Bowling
+
+The game consists of 10 frames. A frame is composed of one or two ball
+throws with 10 pins standing at frame initialization. There are three
+cases for the tabulation of a frame.
+
+* An open frame is where a score of less than 10 is recorded for the
+  frame. In this case the score for the frame is the number of pins
+  knocked down.
+
+* A spare is where all ten pins are knocked down by the second
+  throw. The total value of a spare is 10 plus the number of pins
+  knocked down in their next throw.
+
+* A strike is where all ten pins are knocked down by the first
+  throw. The total value of a strike is 10 plus the number of pins
+  knocked down in the next two throws. If a strike is immediately
+  followed by a second strike, then the value of the first strike
+  cannot be determined until the ball is thrown one more time.
+
+Here is a three frame example:
+
+| Frame 1         | Frame 2       | Frame 3                |
+| :-------------: |:-------------:| :---------------------:|
+| X (strike)      | 5/ (spare)    | 9 0 (open frame)       |
+
+Frame 1 is (10 + 5 + 5) = 20
+
+Frame 2 is (5 + 5 + 9) = 19
+
+Frame 3 is (9 + 0) = 9
+
+This means the current running total is 48.
+
+The tenth frame in the game is a special case. If someone throws a
+strike or a spare then they get a fill ball. Fill balls exist to
+calculate the total of the 10th frame. Scoring a strike or spare on
+the fill ball does not give the player more fill balls. The total
+value of the 10th frame is the total number of pins knocked down.
+
+For a tenth frame of X1/ (strike and a spare), the total value is 20.
+
+For a tenth frame of XXX (three strikes), the total value is 30.
+
+## Requirements
+
+Write code to keep track of the score of a game of bowling. It should
+support two operations:
+
+* `roll(pins : int)` is called each time the player rolls a ball.  The
+  argument is the number of pins knocked down.
+* `score() : int` is called only at the very end of the game.  It
+  returns the total score for that game.
+
+## Rust Installation
+
+Refer to the [exercism help page][help-page] for Rust installation and learning
+resources.
+
+## Writing the Code
+
+Execute the tests with:
+
+```bash
+$ cargo test
+```
+
+All but the first test have been ignored. After you get the first test to
+pass, open the tests source file which is located in the `tests` directory
+and remove the `#[ignore]` flag from the next test and get the tests to pass
+again. Each separate test is a function with `#[test]` flag above it.
+Continue, until you pass every test.
+
+If you wish to run all ignored tests without editing the tests source file, use:
+
+```bash
+$ cargo test -- --ignored
+```
+
+To run a specific test, for example `some_test`, you can use:
+
+```bash
+$ cargo test some_test
+```
+
+If the specific test is ignored use:
+
+```bash
+$ cargo test some_test -- --ignored
+```
+
+To learn more about Rust tests refer to the [online test documentation][rust-tests]
+
+Make sure to read the [Modules][modules] chapter if you
+haven't already, it will help you with organizing your files.
+
+## Further improvements
+
+After you have solved the exercise, please consider using the additional utilities, described in the [installation guide](https://exercism.io/tracks/rust/installation), to further refine your final solution.
+
+To format your solution, inside the solution directory use
+
+```bash
+cargo fmt
+```
+
+To see, if your solution contains some common ineffective use cases, inside the solution directory use
+
+```bash
+cargo clippy --all-targets
+```
+
+## Submitting the solution
+
+Generally you should submit all files in which you implemented your solution (`src/lib.rs` in most cases). If you are using any external crates, please consider submitting the `Cargo.toml` file. This will make the review process faster and clearer.
+
+## Feedback, Issues, Pull Requests
+
+The [exercism/rust](https://github.com/exercism/rust) repository on GitHub is the home for all of the Rust exercises. If you have feedback about an exercise, or want to help implement new exercises, head over there and create an issue. Members of the rust track team are happy to help!
+
+If you want to know more about Exercism, take a look at the [contribution guide](https://github.com/exercism/docs/blob/master/contributing-to-language-tracks/README.md).
+
+[help-page]: https://exercism.io/tracks/rust/learning
+[modules]: https://doc.rust-lang.org/book/ch07-02-defining-modules-to-control-scope-and-privacy.html
+[cargo]: https://doc.rust-lang.org/book/ch14-00-more-about-cargo.html
+[rust-tests]: https://doc.rust-lang.org/book/ch11-02-running-tests.html
+
+## Source
+
+The Bowling Game Kata at but UncleBob [http://butunclebob.com/ArticleS.UncleBob.TheBowlingGameKata](http://butunclebob.com/ArticleS.UncleBob.TheBowlingGameKata)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/rust/bowling/src/lib.rs b/rust/bowling/src/lib.rs
new file mode 100644
index 0000000..bd517a5
--- /dev/null
+++ b/rust/bowling/src/lib.rs
@@ -0,0 +1,45 @@
+#[derive(Debug, PartialEq)]
+pub enum Error {
+    NotEnoughPinsLeft,
+    GameComplete,
+}
+
+#[derive(Debug, Default)]
+pub struct BowlingGame {
+    throws: Vec<u16>,
+    prev: u16
+}
+
+impl BowlingGame {
+    pub fn new() -> Self {
+        Default::default()
+    }
+
+    pub fn roll(&mut self, pins: u16) -> Result<(), Error> {
+        if pins + self.prev > 10 {
+            Err(Error::NotEnoughPinsLeft)
+        } else if self.score().is_some() {
+            Err(Error::GameComplete)
+        } else {
+            self.throws.push(pins);
+            self.prev = if self.prev + pins == 10 { 0 } else { pins };
+            Ok(())
+        }
+    }
+
+    pub fn score(&self) -> Option<u16> {
+        let mut score = 0;
+        let mut stage = 0;
+        for _ in 1..=10 {
+            let first = self.throws.get(stage)?;
+            let second = self.throws.get(stage+1)?;
+            score += first + second;
+            if first + second >= 10 {
+                let third = self.throws.get(stage+2)?;
+                score += third;
+            }
+            stage += if *first == 10 { 1 } else { 2 };
+        }
+        Some(score)
+    }
+}
diff --git a/rust/bowling/tests/bowling.rs b/rust/bowling/tests/bowling.rs
new file mode 100644
index 0000000..92f646f
--- /dev/null
+++ b/rust/bowling/tests/bowling.rs
@@ -0,0 +1,418 @@
+use bowling::*;
+
+#[test]
+fn roll_returns_a_result() {
+    let mut game = BowlingGame::new();
+    assert!(game.roll(0).is_ok());
+}
+
+#[test]
+fn you_cannot_roll_more_than_ten_pins_in_a_single_roll() {
+    let mut game = BowlingGame::new();
+
+    assert_eq!(game.roll(11), Err(Error::NotEnoughPinsLeft));
+}
+
+#[test]
+fn a_game_score_is_some_if_ten_frames_have_been_rolled() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..10 {
+        let _ = game.roll(0);
+        let _ = game.roll(0);
+    }
+
+    assert!(game.score().is_some());
+}
+
+#[test]
+fn you_cannot_score_a_game_with_no_rolls() {
+    let game = BowlingGame::new();
+
+    assert_eq!(game.score(), None);
+}
+
+#[test]
+fn a_game_score_is_none_if_fewer_than_ten_frames_have_been_rolled() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..9 {
+        let _ = game.roll(0);
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), None);
+}
+
+#[test]
+fn a_roll_is_err_if_the_game_is_done() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..10 {
+        let _ = game.roll(0);
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.roll(0), Err(Error::GameComplete));
+}
+
+#[test]
+fn twenty_zero_pin_rolls_scores_zero() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..20 {
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), Some(0));
+}
+
+#[test]
+fn ten_frames_without_a_strike_or_spare() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..10 {
+        let _ = game.roll(3);
+        let _ = game.roll(6);
+    }
+
+    assert_eq!(game.score(), Some(90));
+}
+
+#[test]
+fn spare_in_the_first_frame_followed_by_zeros() {
+    let mut game = BowlingGame::new();
+
+    let _ = game.roll(6);
+    let _ = game.roll(4);
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), Some(10));
+}
+
+#[test]
+fn points_scored_in_the_roll_after_a_spare_are_counted_twice_as_a_bonus() {
+    let mut game = BowlingGame::new();
+
+    let _ = game.roll(6);
+    let _ = game.roll(4);
+    let _ = game.roll(3);
+
+    for _ in 0..17 {
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), Some(16));
+}
+
+#[test]
+fn consecutive_spares_each_get_a_one_roll_bonus() {
+    let mut game = BowlingGame::new();
+
+    let _ = game.roll(5);
+    let _ = game.roll(5);
+    let _ = game.roll(3);
+    let _ = game.roll(7);
+    let _ = game.roll(4);
+
+    for _ in 0..15 {
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), Some(31));
+}
+
+#[test]
+fn if_the_last_frame_is_a_spare_you_get_one_extra_roll_that_is_scored_once() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(5);
+    let _ = game.roll(5);
+    let _ = game.roll(7);
+
+    assert_eq!(game.score(), Some(17));
+}
+
+#[test]
+fn a_strike_earns_ten_points_in_a_frame_with_a_single_roll() {
+    let mut game = BowlingGame::new();
+
+    let _ = game.roll(10);
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), Some(10));
+}
+
+#[test]
+fn points_scored_in_the_two_rolls_after_a_strike_are_counted_twice_as_a_bonus() {
+    let mut game = BowlingGame::new();
+
+    let _ = game.roll(10);
+    let _ = game.roll(5);
+    let _ = game.roll(3);
+
+    for _ in 0..16 {
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), Some(26));
+}
+
+#[test]
+fn consecutive_strikes_each_get_the_two_roll_bonus() {
+    let mut game = BowlingGame::new();
+
+    let _ = game.roll(10);
+    let _ = game.roll(10);
+    let _ = game.roll(10);
+    let _ = game.roll(5);
+    let _ = game.roll(3);
+
+    for _ in 0..12 {
+        let _ = game.roll(0);
+    }
+
+    assert_eq!(game.score(), Some(81));
+}
+
+#[test]
+fn a_strike_in_the_last_frame_earns_a_two_roll_bonus_that_is_counted_once() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+    let _ = game.roll(7);
+    let _ = game.roll(1);
+
+    assert_eq!(game.score(), Some(18));
+}
+
+#[test]
+fn a_spare_with_the_two_roll_bonus_does_not_get_a_bonus_roll() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+    let _ = game.roll(7);
+    let _ = game.roll(3);
+
+    assert_eq!(game.score(), Some(20));
+}
+
+#[test]
+fn strikes_with_the_two_roll_bonus_do_not_get_a_bonus_roll() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+    let _ = game.roll(10);
+    let _ = game.roll(10);
+
+    assert_eq!(game.score(), Some(30));
+}
+
+#[test]
+fn a_strike_with_the_one_roll_bonus_after_a_spare_in_the_last_frame_does_not_get_a_bonus() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(7);
+    let _ = game.roll(3);
+    let _ = game.roll(10);
+
+    assert_eq!(game.score(), Some(20));
+}
+
+#[test]
+fn all_strikes_is_a_perfect_score_of_300() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..12 {
+        let _ = game.roll(10);
+    }
+
+    assert_eq!(game.score(), Some(300));
+}
+
+#[test]
+fn you_cannot_roll_more_than_ten_pins_in_a_single_frame() {
+    let mut game = BowlingGame::new();
+
+    assert!(game.roll(5).is_ok());
+    assert_eq!(game.roll(6), Err(Error::NotEnoughPinsLeft));
+}
+
+#[test]
+fn first_bonus_ball_after_a_final_strike_cannot_score_an_invalid_number_of_pins() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+
+    assert_eq!(game.roll(11), Err(Error::NotEnoughPinsLeft));
+}
+
+#[test]
+fn the_two_balls_after_a_final_strike_cannot_score_an_invalid_number_of_pins() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+
+    assert!(game.roll(5).is_ok());
+    assert_eq!(game.roll(6), Err(Error::NotEnoughPinsLeft));
+}
+
+#[test]
+fn the_two_balls_after_a_final_strike_can_be_a_strike_and_non_strike() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+
+    assert!(game.roll(10).is_ok());
+    assert!(game.roll(6).is_ok());
+}
+
+#[test]
+fn the_two_balls_after_a_final_strike_cannot_be_a_non_strike_followed_by_a_strike() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+
+    assert!(game.roll(6).is_ok());
+    assert_eq!(game.roll(10), Err(Error::NotEnoughPinsLeft));
+}
+
+#[test]
+fn second_bonus_ball_after_a_final_strike_cannot_score_an_invalid_number_of_pins_even_if_first_is_strike(
+) {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+
+    assert!(game.roll(10).is_ok());
+    assert_eq!(game.roll(11), Err(Error::NotEnoughPinsLeft));
+}
+
+#[test]
+fn if_the_last_frame_is_a_strike_you_cannot_score_before_the_extra_rolls_are_taken() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(10);
+
+    assert_eq!(game.score(), None);
+
+    let _ = game.roll(10);
+
+    assert_eq!(game.score(), None);
+
+    let _ = game.roll(10);
+
+    assert!(game.score().is_some());
+}
+
+#[test]
+fn if_the_last_frame_is_a_spare_you_cannot_create_a_score_before_extra_roll_is_taken() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..18 {
+        let _ = game.roll(0);
+    }
+
+    let _ = game.roll(5);
+    let _ = game.roll(5);
+
+    assert_eq!(game.score(), None);
+
+    let _ = game.roll(10);
+
+    assert!(game.score().is_some());
+}
+
+#[test]
+fn cannot_roll_after_bonus_roll_for_spare() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..9 {
+        let _ = game.roll(0);
+        let _ = game.roll(0);
+    }
+    let _ = game.roll(7);
+    let _ = game.roll(3);
+    assert!(game.roll(2).is_ok());
+
+    assert_eq!(game.roll(2), Err(Error::GameComplete));
+}
+
+#[test]
+fn cannot_roll_after_bonus_roll_for_strike() {
+    let mut game = BowlingGame::new();
+
+    for _ in 0..9 {
+        let _ = game.roll(0);
+        let _ = game.roll(0);
+    }
+    let _ = game.roll(10);
+    let _ = game.roll(3);
+    assert!(game.roll(2).is_ok());
+
+    assert_eq!(game.roll(2), Err(Error::GameComplete));
+}
+
+#[test]
+fn last_two_strikes_followed_by_only_last_bonus_with_non_strike_points() {
+    let mut game = BowlingGame::new();
+    for _ in 0..16 {
+        let _ = game.roll(0);
+    }
+    let _ = game.roll(10);
+    let _ = game.roll(10);
+    let _ = game.roll(0);
+    let _ = game.roll(1);
+
+    assert_eq!(game.score(), Some(31));
+}