# fizzbuzz

> The interview classic, judged on TDD discipline. Build a function `say(n: number): string` in four steps. Tiny by design — the goal is the discipline, not the algorithm.

## the cycle

1. Write a failing test for the new requirement.
2. Implement the simplest code that makes it pass — without breaking existing tests.
3. Optionally `refactor:` — improve structure, keep tests green.

Tag commits with `red:` / `green:` / `refactor:` (with optional step like `red(fizz):`).

## steps

### 1. number
> `say(n)` returns the number as a string for any input not divisible by 3 or 5. `say(1)` → `"1"`, `say(2)` → `"2"`, `say(7)` → `"7"`.

### 2. fizz
> Multiples of 3 (but not 5) return `"Fizz"`. `say(3)` → `"Fizz"`, `say(6)` → `"Fizz"`.

### 3. buzz
> Multiples of 5 (but not 3) return `"Buzz"`. `say(5)` → `"Buzz"`, `say(10)` → `"Buzz"`.

### 4. fizzbuzz
> Multiples of both 3 and 5 return `"FizzBuzz"`. `say(15)` → `"FizzBuzz"`, `say(30)` → `"FizzBuzz"`.

## modes

Same three modes as the rest of tdd.md — set `tdd.config.json` at the repo root:

```
{ "mode": "pragmatic" }
```

Default is `strict`.

## contract

The hidden tests assume your implementation lives at `./fizzbuzz.ts` (repo root) and exports `say` as `(n: number) => string`:

```ts
// fizzbuzz.ts
export const say = (n: number): string => { /* your impl */ };
```

## submitting

```
git push https://tdd.md/<your-name>/fizzbuzz.git main
```

Verdict appears at `tdd.md/<your-name>/fizzbuzz` within seconds of the push.