added tests

test.py

@@ -0,0 +1,55 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+from mathstream import StreamNumber, add, sub, mul, div, pow, clear_logs
+
+NUMBERS_DIR = Path(__file__).parent / "tests"
+
+def write_number(name: str, digits: str) -> StreamNumber:
+    """Persist digits to disk and return a streamable handle."""
+    NUMBERS_DIR.mkdir(parents=True, exist_ok=True)
+    target = NUMBERS_DIR / f"{name}.txt"
+    target.write_text(digits, encoding="utf-8")
+    return StreamNumber(target)
+
+
+def read_number(num: StreamNumber) -> str:
+    """Collapse streamed chunks back into a concrete string."""
+    return "".join(num.stream())
+
+
+def check(label: str, result: StreamNumber, expected: str) -> None:
+    actual = read_number(result)
+    assert (
+        actual == expected
+    ), f"{label} expected {expected}, got {actual}"
+    print(f"{label} = {actual}")
+
+
+def main() -> None:
+    clear_logs()
+
+    # Build a handful of example operands on disk.
+    big = write_number("huge", "98765432123456789")
+    small = write_number("tiny", "34567")
+    negative = write_number("negative", "-1200")
+    exponent = write_number("power", "5")
+
+    # Showcase the core operations.
+    total = add(big, small)
+    difference = sub(big, small)
+    product = mul(small, negative)
+    quotient = div(big, small)
+    powered = pow(small, exponent)
+
+    print("Operands stored under:", NUMBERS_DIR)
+    check("huge + tiny", total, "98765432123491356")
+    check("huge - tiny", difference, "98765432123422222")
+    check("tiny * negative", product, "-41480400")
+    check("huge // tiny", quotient, "2857217349595")
+    check("tiny ** power", powered, "49352419431622775997607")
+
+
+if __name__ == "__main__":
+    main()

tests/huge.txt

@@ -0,0 +1 @@
+98765432123456789

tests/negative.txt

@@ -0,0 +1 @@
+-1200

tests/power.txt

@@ -0,0 +1 @@
+5

tests/tiny.txt

@@ -0,0 +1 @@
+34567