Refactor password generation with helpers

src/tests/test_password_helpers.py

@@ -0,0 +1,55 @@
+import string
+from password_manager.password_generation import PasswordGenerator
+
+
+class DummyEnc:
+    def derive_seed_from_mnemonic(self, mnemonic):
+        return b"\x00" * 32
+
+
+class DummyBIP85:
+    def derive_entropy(self, index: int, bytes_len: int, app_no: int = 32) -> bytes:
+        return bytes((index + i) % 256 for i in range(bytes_len))
+
+
+def make_generator():
+    pg = PasswordGenerator.__new__(PasswordGenerator)
+    pg.encryption_manager = DummyEnc()
+    pg.bip85 = DummyBIP85()
+    return pg
+
+
+def test_derive_password_entropy_length():
+    pg = make_generator()
+    dk = pg._derive_password_entropy(index=1)
+    assert isinstance(dk, bytes)
+    assert len(dk) == 32
+    dk2 = pg._derive_password_entropy(index=2)
+    assert dk != dk2
+
+
+def test_map_entropy_to_chars_only_uses_alphabet():
+    pg = make_generator()
+    alphabet = string.ascii_letters + string.digits
+    mapped = pg._map_entropy_to_chars(b"\x00\x01\x02", alphabet)
+    assert all(c in alphabet for c in mapped)
+    assert len(mapped) == 3
+
+
+def test_enforce_complexity_minimum_counts():
+    pg = make_generator()
+    alphabet = string.ascii_letters + string.digits + string.punctuation
+    dk = bytes(range(32))
+    result = pg._enforce_complexity("a" * 32, alphabet, dk)
+    assert sum(1 for c in result if c.isupper()) >= 2
+    assert sum(1 for c in result if c.islower()) >= 2
+    assert sum(1 for c in result if c.isdigit()) >= 2
+    assert sum(1 for c in result if c in string.punctuation) >= 2
+
+
+def test_shuffle_deterministically_repeatable():
+    pg = make_generator()
+    dk = bytes(range(32))
+    pw1 = pg._shuffle_deterministically("abcdef", dk)
+    pw2 = pg._shuffle_deterministically("abcdef", dk)
+    assert pw1 == pw2