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Diffstat (limited to 'python/slugid/test.py')
| -rw-r--r-- | python/slugid/test.py | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/python/slugid/test.py b/python/slugid/test.py new file mode 100644 index 000000000..55103453a --- /dev/null +++ b/python/slugid/test.py @@ -0,0 +1,167 @@ +# Licensed under the Mozilla Public Licence 2.0. +# https://www.mozilla.org/en-US/MPL/2.0 + +import uuid +import slugid + + +def testEncode(): + """ Test that we can correctly encode a "non-nice" uuid (with first bit + set) to its known slug. The specific uuid was chosen since it has a slug + which contains both `-` and `_` characters.""" + + # 10000000010011110011111111001000110111111100101101001011000001101000100111111011101011101111101011010101111000011000011101010100.... + # <8 ><0 ><4 ><f ><3 ><f ><c ><8 ><d ><f ><c ><b ><4 ><b ><0 ><6 ><8 ><9 ><f ><b ><a ><e ><f ><a ><d ><5 ><e ><1 ><8 ><7 ><5 ><4 > + # < g >< E >< 8 >< _ >< y >< N >< _ >< L >< S >< w >< a >< J >< - >< 6 >< 7 >< 6 >< 1 >< e >< G >< H >< V >< A > + uuid_ = uuid.UUID('{804f3fc8-dfcb-4b06-89fb-aefad5e18754}') + expectedSlug = 'gE8_yN_LSwaJ-6761eGHVA' + actualSlug = slugid.encode(uuid_) + + assert expectedSlug == actualSlug, "UUID not correctly encoded into slug: '" + expectedSlug + "' != '" + actualSlug + "'" + + +def testDecode(): + """ Test that we can decode a "non-nice" slug (first bit of uuid is set) + that begins with `-`""" + + # 11111011111011111011111011111011111011111011111001000011111011111011111111111111111111111111111111111111111111111111111111111101.... + # <f ><b ><e ><f ><b ><e ><f ><b ><e ><f ><b ><e ><4 ><3 ><e ><f ><b ><f ><f ><f ><f ><f ><f ><f ><f ><f ><f ><f ><f ><f ><f ><d > + # < - >< - >< - >< - >< - >< - >< - >< - >< Q >< - >< - >< - >< _ >< _ >< _ >< _ >< _ >< _ >< _ >< _ >< _ >< Q > + slug = '--------Q--__________Q' + expectedUuid = uuid.UUID('{fbefbefb-efbe-43ef-bfff-fffffffffffd}') + actualUuid = slugid.decode(slug) + + assert expectedUuid == actualUuid, "Slug not correctly decoded into uuid: '" + str(expectedUuid) + "' != '" + str(actualUuid) + "'" + + +def testUuidEncodeDecode(): + """ Test that 10000 v4 uuids are unchanged after encoding and then decoding them""" + + for i in range(0, 10000): + uuid1 = uuid.uuid4() + slug = slugid.encode(uuid1) + uuid2 = slugid.decode(slug) + + assert uuid1 == uuid2, "Encode and decode isn't identity: '" + str(uuid1) + "' != '" + str(uuid2) + "'" + + +def testSlugDecodeEncode(): + """ Test that 10000 v4 slugs are unchanged after decoding and then encoding them.""" + + for i in range(0, 10000): + slug1 = slugid.v4() + uuid_ = slugid.decode(slug1) + slug2 = slugid.encode(uuid_) + + assert slug1 == slug2, "Decode and encode isn't identity" + + +def testSpreadNice(): + """ Make sure that all allowed characters can appear in all allowed + positions within the "nice" slug. In this test we generate over a thousand + slugids, and make sure that every possible allowed character per position + appears at least once in the sample of all slugids generated. We also make + sure that no other characters appear in positions in which they are not + allowed. + + base 64 encoding char -> value: + ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_ + 0 1 2 3 4 5 6 + 0123456789012345678901234567890123456789012345678901234567890123 + + e.g. from this we can see 'j' represents 35 in base64 + + The following comments show the 128 bits of the v4 uuid in binary, hex and + base 64 encodings. The 6 fixed bits (`0`/`1`) according to RFC 4122, plus + the first (most significant) fixed bit (`0`) are shown among the 121 + arbitrary value bits (`.`/`x`). The `x` means the same as `.` but just + highlights which bits are grouped together for the respective encoding. + + schema: + <..........time_low............><...time_mid...><time_hi_+_vers><clk_hi><clk_lo><.....................node.....................> + + bin: 0xxx............................................0100............10xx............................................................ + hex: $A <01><02><03><04><05><06><07><08><09><10><11> 4 <13><14><15> $B <17><18><19><20><21><22><23><24><25><26><27><28><29><30><31> + + => $A in {0, 1, 2, 3, 4, 5, 6, 7} (0b0xxx) + => $B in {8, 9, A, B} (0b10xx) + + bin: 0xxxxx..........................................0100xx......xxxx10............................................................xx0000 + b64: $C < 01 >< 02 >< 03 >< 04 >< 05 >< 06 >< 07 > $D < 09 > $E < 11 >< 12 >< 13 >< 14 >< 15 >< 16 >< 17 >< 18 >< 19 >< 20 > $F + + => $C in {A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, a, b, c, d, e, f} (0b0xxxxx) + => $D in {Q, R, S, T} (0b0100xx) + => $E in {C, G, K, O, S, W, a, e, i, m, q, u, y, 2, 6, -} (0bxxxx10) + => $F in {A, Q, g, w} (0bxx0000)""" + + charsAll = ''.join(sorted('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_')) + # 0 - 31: 0b0xxxxx + charsC = ''.join(sorted('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdef')) + # 16, 17, 18, 19: 0b0100xx + charsD = ''.join(sorted('QRST')) + # 2, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58, 62: 0bxxxx10 + charsE = ''.join(sorted('CGKOSWaeimquy26-')) + # 0, 16, 32, 48: 0bxx0000 + charsF = ''.join(sorted('AQgw')) + expected = [charsC, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsD, charsAll, charsE, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsF] + spreadTest(slugid.nice, expected) + + +def testSpreadV4(): + """ This test is the same as niceSpreadTest but for slugid.v4() rather than + slugid.nice(). The only difference is that a v4() slug can start with any of + the base64 characters since the first six bits of the uuid are random.""" + + charsAll = ''.join(sorted('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_')) + # 16, 17, 18, 19: 0b0100xx + charsD = ''.join(sorted('QRST')) + # 2, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58, 62: 0bxxxx10 + charsE = ''.join(sorted('CGKOSWaeimquy26-')) + # 0, 16, 32, 48: 0bxx0000 + charsF = ''.join(sorted('AQgw')) + expected = [charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsD, charsAll, charsE, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsAll, charsF] + spreadTest(slugid.v4, expected) + + +def spreadTest(generator, expected): + """ `spreadTest` runs a test against the `generator` function, to check that + when calling it 64*40 times, the range of characters per string position it + returns matches the array `expected`, where each entry in `expected` is a + string of all possible characters that should appear in that position in the + string, at least once in the sample of 64*40 responses from the `generator` + function""" + # k is an array which stores which characters were found at which + # positions. It has one entry per slugid character, therefore 22 entries. + # Each entry is a dict with a key for each character found, and its value + # as the number of times that character appeared at that position in the + # slugid in the large sample of slugids generated in this test. + k = [{}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}] + + # Generate a large sample of slugids, and record what characters appeared + # where... A monte-carlo test has demonstrated that with 64 * 20 + # iterations, no failure occurred in 1000 simulations, so 64 * 40 should be + # suitably large to rule out false positives. + for i in range(0, 64 * 40): + slug = generator() + assert len(slug) == 22 + for j in range(0, 22): + if slug[j] in k[j]: + k[j][slug[j]] = k[j][slug[j]] + 1 + else: + k[j][slug[j]] = 1 + + # Compose results into an array `actual`, for comparison with `expected` + actual = [] + for j in range(0, len(k)): + actual.append('') + for a in k[j].keys(): + if k[j][a] > 0: + actual[j] += a + # sort for easy comparison + actual[j] = ''.join(sorted(actual[j])) + + assert arraysEqual(expected, actual), "In a large sample of generated slugids, the range of characters found per character position in the sample did not match expected results.\n\nExpected: " + str(expected) + "\n\nActual: " + str(actual) + +def arraysEqual(a, b): + """ returns True if arrays a and b are equal""" + return cmp(a, b) == 0 |