# STATUS-eval — Builder

## DONE

## Current state

Gate: D1, D2, D3, D4, D5 — all PASS (Adversary verified @2026-06-15T00:54Z)

---

## Claims

### D1 — arithmetic

**What:** `evaluate(parse(tokenize(s)))` correct for `+ - * /`, precedence, parens, unary minus.

**How to verify:**
```bash
python -m unittest calc.test_evaluator.TestArithmetic -q
```

**Expected:** 0 failures. Specific cases:
- `"2+3*4"` → 14
- `"(2+3)*4"` → 20
- `"8-3-2"` → 3
- `"-2+5"` → 3
- `"2*-3"` → -6

**Where:** `calc/evaluator.py` + `calc/test_evaluator.py`

---

### D2 — division

**What:** `/` is true division; `EvalError` raised on division by zero, not bare `ZeroDivisionError`.

**How to verify:**
```bash
python -m unittest calc.test_evaluator.TestDivision -q
```

**Expected:** 0 failures. Includes:
- `"7/2"` → 3.5
- `"1/0"` → `EvalError`
- `"5/(3-3)"` → `EvalError`
- No `ZeroDivisionError` escaping the API

**Where:** `calc/evaluator.py:18-21`

---

### D3 — result type

**What:** Whole-valued results print without `.0`; non-whole as float.

**How to verify:**
```bash
python -m unittest calc.test_evaluator.TestResultType -q
python calc.py "4/2"   # should print: 2
python calc.py "7/2"   # should print: 3.5
```

**Expected:** 0 failures; `4/2` → `2` (no dot), `7/2` → `3.5`.

**Rule:** The `_fmt()` function in `calc.py` checks `value.is_integer()` on floats; if true, casts to `int` for display.

**Where:** `calc.py:_fmt()`, `calc/test_evaluator.py:TestResultType`

---

### D4 — CLI

**What:** `python calc.py "2+3*4"` prints `14` and exits 0; invalid expression prints error to stderr and exits non-zero (no traceback).

**How to verify:**
```bash
python calc.py "2+3*4"     # stdout: 14, exit 0
python calc.py "(2+3)*4"   # stdout: 20, exit 0
python calc.py "7/2"       # stdout: 3.5, exit 0
python calc.py "4/2"       # stdout: 2, exit 0
python calc.py "1/0"       # stderr: error: ..., exit 1
python calc.py "1 +"       # stderr: error: ..., exit 1
```

**Expected:** Exact outputs as above. All errors caught by `(LexError, ParseError, EvalError)` — no Python traceback.

**Where:** `calc.py`

---

### D5 — tests green + end-to-end

**What:** Full unittest suite (lex + parse + eval) passes with 0 failures; CLI checks cover D4.

**How to verify:**
```bash
python -m unittest -q
```

**Expected:**
```
Ran 68 tests in ~0.2s

OK
```

All 68 tests pass: 24 lex + 22 parse + 22 eval (including 6 CLI subprocess tests).

**Commit sha:** (see latest commit after push)

**Where:** `calc/test_lexer.py`, `calc/test_parser.py`, `calc/test_evaluator.py`