Cybersecurity-Projects/PROJECTS/beginner/base64-tool/tests/test_encoders.py

276 lines
8.5 KiB
Python

"""
©AngelaMos | 2026
test_encoders.py
Unit tests for all encoder and decoder functions in encoders.py
Tests each format with known-good inputs, full roundtrips, whitespace
tolerance in decoders, binary and unicode data, and invalid input
rejection. Also covers the ENCODER_REGISTRY dispatch via encode() and
decode(), and the try_decode() safe wrapper.
Tests:
TestBase64 - encode, decode, roundtrip, whitespace, binary, unicode, invalid input
TestBase64Url - URL-safe character guarantees and roundtrip
TestBase32 - encode, decode, lowercase tolerance, padding
TestHex - encode, decode, colon/space/dash separator variants
TestUrl - percent-encoding, form-encoding (plus signs), roundtrip
TestRegistryDispatch - parametrized roundtrip for all formats, try_decode
Connects to:
encoders.py - all functions under test
constants.py - imports EncodingFormat
"""
import binascii
import pytest
from base64_tool.constants import EncodingFormat
from base64_tool.encoders import (
decode,
decode_base32,
decode_base64,
decode_base64url,
decode_hex,
decode_url,
encode,
encode_base32,
encode_base64,
encode_base64url,
encode_hex,
encode_url,
try_decode,
)
class TestBase64:
def test_encode_simple_text(self) -> None:
"""
Checks that 'Hello World' encodes to the known base64 string
"""
assert encode_base64(b"Hello World") == "SGVsbG8gV29ybGQ="
def test_decode_simple_text(self) -> None:
"""
Checks that a known base64 string decodes back to 'Hello World'
"""
assert decode_base64("SGVsbG8gV29ybGQ=") == b"Hello World"
def test_roundtrip(self) -> None:
"""
Encodes then decodes an ASCII sentence and checks it matches the original
"""
original = b"The quick brown fox jumps over the lazy dog"
assert decode_base64(encode_base64(original)) == original
def test_encode_empty(self) -> None:
"""
Checks that encoding empty bytes produces an empty string
"""
assert encode_base64(b"") == ""
def test_decode_empty(self) -> None:
"""
Checks that decoding an empty string produces empty bytes
"""
assert decode_base64("") == b""
def test_encode_binary_data(self) -> None:
"""
Encodes all 256 byte values and checks the roundtrip is lossless
"""
data = bytes(range(256))
assert decode_base64(encode_base64(data)) == data
def test_decode_with_whitespace(self) -> None:
"""
Checks that a base64 string split across newlines still decodes correctly
"""
encoded = "SGVs\nbG8g\nV29y\nbGQ="
assert decode_base64(encoded) == b"Hello World"
def test_decode_invalid_raises(self) -> None:
"""
Checks that decoding garbage characters raises an exception
"""
with pytest.raises((ValueError, binascii.Error)):
decode_base64("!!!invalid!!!")
def test_encode_unicode(self) -> None:
"""
Checks that multi-byte unicode survives a base64 roundtrip
"""
data = "Hello 世界".encode()
decoded = decode_base64(encode_base64(data))
assert decoded == data
class TestBase64Url:
def test_encode_with_url_chars(self) -> None:
"""
Checks that URL-safe base64 never emits + or / characters
"""
data = b"\xfb\xff\xfe"
encoded = encode_base64url(data)
assert "+" not in encoded
assert "/" not in encoded
def test_decode_url_safe(self) -> None:
"""
Checks that data containing / and + round-trips through URL-safe base64
"""
result = decode_base64url(encode_base64url(b"test/path+query"))
assert result == b"test/path+query"
def test_roundtrip(self) -> None:
"""
Encodes then decodes a URL string and checks it matches the original
"""
original = b"https://example.com?token=abc+def/ghi"
assert decode_base64url(encode_base64url(original)) == original
class TestBase32:
def test_encode_simple(self) -> None:
"""
Checks that 'Hello' encodes to its known base32 representation
"""
assert encode_base32(b"Hello") == "JBSWY3DP"
def test_decode_simple(self) -> None:
"""
Checks that a known base32 string decodes to 'Hello'
"""
assert decode_base32("JBSWY3DP") == b"Hello"
def test_roundtrip(self) -> None:
"""
Encodes then decodes a short sentence and checks it matches the original
"""
original = b"Base32 encoding test"
assert decode_base32(encode_base32(original)) == original
def test_decode_lowercase_accepted(self) -> None:
"""
Checks that lowercase base32 input is accepted and decoded correctly
"""
assert decode_base32("jbswy3dp") == b"Hello"
def test_decode_with_padding(self) -> None:
"""
Checks that a padded base32 string decodes to 'Hello World'
"""
assert decode_base32("JBSWY3DPEBLW64TMMQ======") == b"Hello World"
class TestHex:
def test_encode_simple(self) -> None:
"""
Checks that bytes \\xca\\xfe encode to the hex string 'cafe'
"""
assert encode_hex(b"\xca\xfe") == "cafe"
def test_decode_simple(self) -> None:
"""
Checks that 'cafe' decodes to the bytes \\xca\\xfe
"""
assert decode_hex("cafe") == b"\xca\xfe"
def test_decode_with_colons(self) -> None:
"""
Checks that colon-separated hex decodes correctly
"""
assert decode_hex("ca:fe:ba:be") == b"\xca\xfe\xba\xbe"
def test_decode_with_spaces(self) -> None:
"""
Checks that space-separated hex decodes correctly
"""
assert decode_hex("ca fe ba be") == b"\xca\xfe\xba\xbe"
def test_decode_with_dashes(self) -> None:
"""
Checks that dash-separated hex decodes correctly
"""
assert decode_hex("ca-fe-ba-be") == b"\xca\xfe\xba\xbe"
def test_decode_uppercase(self) -> None:
"""
Checks that uppercase hex input decodes correctly
"""
assert decode_hex("CAFE") == b"\xca\xfe"
def test_roundtrip(self) -> None:
"""
Encodes then decodes a known string and checks no data is lost
"""
original = b"Hello World"
assert decode_hex(encode_hex(original)) == original
class TestUrl:
def test_encode_special_chars(self) -> None:
"""
Checks that spaces and ampersands are percent-encoded
"""
result = encode_url(b"hello world&foo=bar")
assert " " not in result
assert "&" not in result
def test_decode_percent_encoded(self) -> None:
"""
Checks that %20 decodes to a space
"""
assert decode_url("hello%20world") == b"hello world"
def test_roundtrip(self) -> None:
"""
Encodes then decodes a URL with a query string and checks it matches the original
"""
original = b"path/to/file?key=value&other=test"
assert decode_url(encode_url(original)) == original
def test_form_encode_space_as_plus(self) -> None:
"""
Checks that form encoding turns spaces into + rather than %20
"""
result = encode_url(b"hello world", form = True)
assert "+" in result
assert "%20" not in result
def test_form_decode_plus_as_space(self) -> None:
"""
Checks that form decoding turns + back into a space
"""
assert decode_url("hello+world", form = True) == b"hello world"
class TestRegistryDispatch:
@pytest.mark.parametrize("fmt", list(EncodingFormat))
def test_encode_decode_roundtrip(
self,
fmt: EncodingFormat,
) -> None:
"""
Checks that all registered formats produce a lossless roundtrip via encode() and decode()
"""
original = b"roundtrip test data"
encoded = encode(original, fmt)
decoded = decode(encoded, fmt)
assert decoded == original
def test_try_decode_valid(self) -> None:
"""
Checks that try_decode returns the correct bytes for valid input
"""
result = try_decode("SGVsbG8=", EncodingFormat.BASE64)
assert result == b"Hello"
def test_try_decode_invalid_returns_none(self) -> None:
"""
Checks that try_decode returns None instead of raising for garbage input
"""
result = try_decode("!!!bad!!!", EncodingFormat.BASE64)
assert result is None