Add tests for all functions of each algorithm against AEGIS test vectors (JSON). Incremental updates are tested with randomized splits to catch a variety of errors.

tests/util.py

@@ -0,0 +1,28 @@
+import random
+
+
+_rng = random.SystemRandom()
+
+
+def random_split_bytes(data: bytes) -> list[bytes]:
+    """Split ``data`` into one to a few random-sized chunks.
+
+    Keeps chunk sizes positive and varies the number of pieces between 1 and 4.
+    """
+    if not data:
+        return [data]
+    if len(data) == 1:
+        return [data]
+
+    max_chunks = min(4, len(data))
+    chunks = _rng.randint(1, max_chunks)
+    if chunks == 1:
+        return [data]
+
+    cut_points = sorted(_rng.sample(range(1, len(data)), chunks - 1))
+    start = 0
+    parts = []
+    for stop in (*cut_points, len(data)):
+        parts.append(data[start:stop])
+        start = stop
+    return parts