# STATUS — phase: eval (Builder)

## DONE

Gate: D1 D2 D3 D4 D5 — Adversary PASS @2026-06-15T01:58:00Z. Phase complete.

## What was built

- `calc/evaluator.py` — `evaluate(node) -> int | float`; `EvalError` for bad nodes / division by zero
- `calc/test_evaluator.py` — 15 unittest cases covering D1–D3
- `calc.py` (repo root) — CLI: `python calc.py "<expr>"`

## Commit SHA

See `git log --oneline -1` on origin/main after this push.

## Verify commands (cold — run from repo root)

```bash
python -m unittest -q
# Expected: Ran 56 tests in <N>s / OK

python calc.py "2+3*4"    # Expected: 14
python calc.py "(2+3)*4"  # Expected: 20
python calc.py "7/2"      # Expected: 3.5
python calc.py "4/2"      # Expected: 2
python calc.py "1/0"      # Expected: prints error to stderr, exits 1
python calc.py "1 +"      # Expected: prints error to stderr, exits 1
```

## Gate mapping

| Gate | DoD | Verify |
|------|-----|--------|
| D1 | arithmetic: `+ - * /`, precedence, parens, unary minus | `python -m unittest -q` (TestArithmetic) |
| D2 | true division; `EvalError` on div-by-zero (not bare `ZeroDivisionError`) | `python -m unittest -q` (TestDivision) |
| D3 | whole-valued → int (no `.0`); non-whole → float | `python -m unittest -q` (TestResultType) |
| D4 | `python calc.py "2+3*4"` → 14 exit 0; error → stderr + exit 1 | manual CLI commands above |
| D5 | 56 tests total (lex+parse+eval), 0 failures | `python -m unittest -q` |

## Result type rule (D3)

Division result is normalised: `result = left / right; return int(result) if result == int(result) else result`.
The CLI's `_fmt` calls `str(result)`, so `int` prints as `"2"` and `float` prints as `"3.5"`.