update to mypy 0.620 and make tests pass again

Fixes #408

Pipfile

@@ -15,7 +15,7 @@ coverage = "*"
 flake8 = "*"
 flake8-bugbear = "*"
 flake8-mypy = "*"
-mypy = "*"
+mypy = ">=0.620"
 readme_renderer = "*"
 recommonmark = "*"
 Sphinx = "*"

Pipfile.lock

@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "ac93441465d67f28d5888486c43ced0b49c4a42c315a8d453064a6441fbf3de0"
+            "sha256": "83e7921ad3bcb0c1ee6c654ef6c2b737dd72629c2541f387ac186bedc55d33af"
         },
         "pipfile-spec": 6,
         "requires": {},
@@ -49,10 +49,10 @@
     "develop": {
         "alabaster": {
             "hashes": [
-                "sha256:2eef172f44e8d301d25aff8068fddd65f767a3f04b5f15b0f4922f113aa1c732",
+                "sha256:674bb3bab080f598371f4443c5008cbfeb1a5e622dd312395d2d82af2c54c456",
-                "sha256:37cdcb9e9954ed60912ebc1ca12a9d12178c26637abdf124e3cde2341c257fe0"
+                "sha256:b63b1f4dc77c074d386752ec4a8a7517600f6c0db8cd42980cae17ab7b3275d7"
             ],
-            "version": "==0.7.10"
+            "version": "==0.7.11"
         },
         "aspy.yaml": {
             "hashes": [
@@ -85,10 +85,10 @@
         },
         "cached-property": {
             "hashes": [
-                "sha256:67acb3ee8234245e8aea3784a492272239d9c4b487eba2fdcce9d75460d34520",
+                "sha256:630fdbf0f4ac7d371aa866016eba1c3ac43e9032246748d4994e67cb05f99bc4",
-                "sha256:bf093e640b7294303c7cc7ba3212f00b7a07d0416c1d923465995c9ef860a139"
+                "sha256:f1f9028757dc40b4cb0fd2234bd7b61a302d7b84c683cb8c2c529238a24b8938"
             ],
-            "version": "==1.4.2"
+            "version": "==1.4.3"
         },
         "certifi": {
             "hashes": [
@@ -103,9 +103,12 @@
                 "sha256:1553d1e99f035ace1c0544050622b7bc963374a00c467edafac50ad7bd276aef",
                 "sha256:1b0493c091a1898f1136e3f4f991a784437fac3673780ff9de3bcf46c80b6b50",
                 "sha256:2ba8a45822b7aee805ab49abfe7eec16b90587f7f26df20c71dd89e45a97076f",
+                "sha256:3bb6bd7266598f318063e584378b8e27c67de998a43362e8fce664c54ee52d30",
                 "sha256:3c85641778460581c42924384f5e68076d724ceac0f267d66c757f7535069c93",
                 "sha256:3eb6434197633b7748cea30bf0ba9f66727cdce45117a712b29a443943733257",
+                "sha256:495c5c2d43bf6cebe0178eb3e88f9c4aa48d8934aa6e3cddb865c058da76756b",
                 "sha256:4c91af6e967c2015729d3e69c2e51d92f9898c330d6a851bf8f121236f3defd3",
+                "sha256:57b2533356cb2d8fac1555815929f7f5f14d68ac77b085d2326b571310f34f6e",
                 "sha256:770f3782b31f50b68627e22f91cb182c48c47c02eb405fd689472aa7b7aa16dc",
                 "sha256:79f9b6f7c46ae1f8ded75f68cf8ad50e5729ed4d590c74840471fc2823457d04",
                 "sha256:7a33145e04d44ce95bcd71e522b478d282ad0eafaf34fe1ec5bbd73e662f22b6",
@@ -114,11 +117,13 @@
                 "sha256:95d5251e4b5ca00061f9d9f3d6fe537247e145a8524ae9fd30a2f8fbce993b5b",
                 "sha256:9d1d3e63a4afdc29bd76ce6aa9d58c771cd1599fbba8cf5057e7860b203710dd",
                 "sha256:a36c5c154f9d42ec176e6e620cb0dd275744aa1d804786a71ac37dc3661a5e95",
+                "sha256:a6a5cb8809091ec9ac03edde9304b3ad82ad4466333432b16d78ef40e0cce0d5",
                 "sha256:ae5e35a2c189d397b91034642cb0eab0e346f776ec2eb44a49a459e6615d6e2e",
                 "sha256:b0f7d4a3df8f06cf49f9f121bead236e328074de6449866515cea4907bbc63d6",
                 "sha256:b75110fb114fa366b29a027d0c9be3709579602ae111ff61674d28c93606acca",
                 "sha256:ba5e697569f84b13640c9e193170e89c13c6244c24400fc57e88724ef610cd31",
                 "sha256:be2a9b390f77fd7676d80bc3cdc4f8edb940d8c198ed2d8c0be1319018c778e1",
+                "sha256:ca1bd81f40adc59011f58159e4aa6445fc585a32bb8ac9badf7a2c1aa23822f2",
                 "sha256:d5d8555d9bfc3f02385c1c37e9f998e2011f0db4f90e250e5bc0c0a85a813085",
                 "sha256:e55e22ac0a30023426564b1059b035973ec82186ddddbac867078435801c7801",
                 "sha256:e90f17980e6ab0f3c2f3730e56d1fe9bcba1891eeea58966e89d352492cc74f4",
@@ -181,10 +186,7 @@
             "hashes": [
                 "sha256:03481e81d558d30d230bc12999e3edffe392d244349a90f4ef9b88425fac74ba",
                 "sha256:0b136648de27201056c1869a6c0d4e23f464750fd9a9ba9750b8336a244429ed",
-                "sha256:104ab3934abaf5be871a583541e8829d6c19ce7bde2923b2751e0d3ca44db60a",
-                "sha256:15b111b6a0f46ee1a485414a52a7ad1d703bdf984e9ed3c288a4414d3871dcbd",
                 "sha256:198626739a79b09fa0a2f06e083ffd12eb55449b5f8bfdbeed1df4910b2ca640",
-                "sha256:1c383d2ef13ade2acc636556fd544dba6e14fa30755f26812f54300e401f98f2",
                 "sha256:28b2191e7283f4f3568962e373b47ef7f0392993bb6660d079c62bd50fe9d162",
                 "sha256:2eb564bbf7816a9d68dd3369a510be3327f1c618d2357fa6b1216994c2e3d508",
                 "sha256:337ded681dd2ef9ca04ef5d93cfc87e52e09db2594c296b4a0a3662cb1b41249",
@@ -205,16 +207,11 @@
                 "sha256:7e1fe19bd6dce69d9fd159d8e4a80a8f52101380d5d3a4d374b6d3eae0e5de9c",
                 "sha256:8c3cb8c35ec4d9506979b4cf90ee9918bc2e49f84189d9bf5c36c0c1119c6558",
                 "sha256:9d6dd10d49e01571bf6e147d3b505141ffc093a06756c60b053a859cb2128b1f",
-                "sha256:9e112fcbe0148a6fa4f0a02e8d58e94470fc6cb82a5481618fea901699bf34c4",
-                "sha256:ac4fef68da01116a5c117eba4dd46f2e06847a497de5ed1d64bb99a5fda1ef91",
-                "sha256:b8815995e050764c8610dbc82641807d196927c3dbed207f0a079833ffcf588d",
                 "sha256:be6cfcd8053d13f5f5eeb284aa8a814220c3da1b0078fa859011c7fffd86dab9",
                 "sha256:c1bb572fab8208c400adaf06a8133ac0712179a334c09224fb11393e920abcdd",
                 "sha256:de4418dadaa1c01d497e539210cb6baa015965526ff5afc078c57ca69160108d",
                 "sha256:e05cb4d9aad6233d67e0541caa7e511fa4047ed7750ec2510d466e806e0255d6",
-                "sha256:e4d96c07229f58cb686120f168276e434660e4358cc9cf3b0464210b04913e77",
+                "sha256:f3f501f345f24383c0000395b26b726e46758b71393267aeae0bd36f8b3ade80"
-                "sha256:f3f501f345f24383c0000395b26b726e46758b71393267aeae0bd36f8b3ade80",
-                "sha256:f8a923a85cb099422ad5a2e345fe877bbc89a8a8b23235824a93488150e45f6e"
             ],
             "index": "pypi",
             "version": "==4.5.1"
@@ -266,17 +263,17 @@
         },
         "identify": {
             "hashes": [
-                "sha256:067c206bb7a6926d30de0e77d6297729a176c0aa8b2d810a5be809cb46b045b2",
+                "sha256:0bab212939e3e83caf60788fac9bda5ea4a496f9147ed4746bb04f10ec6c0cbf",
-                "sha256:5eae91e34881bed02ea4f8c3886df8bd1232536d6f0dbf0405ff734268b7f425"
+                "sha256:264f34cbd4002d5b2f4b323ae9e5776a16189363d82627f46570b9c703fea448"
             ],
-            "version": "==1.0.18"
+            "version": "==1.1.3"
         },
         "idna": {
             "hashes": [
-                "sha256:2c6a5de3089009e3da7c5dde64a141dbc8551d5b7f6cf4ed7c2568d0cc520a8f",
+                "sha256:156a6814fb5ac1fc6850fb002e0852d56c0c8d2531923a51032d1b70760e186e",
-                "sha256:8c7309c718f94b3a625cb648ace320157ad16ff131ae0af362c9f21b80ef6ec4"
+                "sha256:684a38a6f903c1d71d6d5fac066b58d7768af4de2b832e426ec79c30daa94a16"
             ],
-            "version": "==2.6"
+            "version": "==2.7"
         },
         "imagesize": {
             "hashes": [
@@ -307,17 +304,17 @@
         },
         "mypy": {
             "hashes": [
-                "sha256:01cf289838f266ae7c6550c813181ee77d21eac9459dbf067e7a95a0a2db9721",
+                "sha256:673ea75fb750289b7d1da1331c125dc62fc1c3a8db9129bb372ae7b7d5bf300a",
-                "sha256:bc251cb31bc236d9fe4bcc442c994c45fff2541f7161ee52dc949741fe9ca3dd"
+                "sha256:c770605a579fdd4a014e9f0a34b6c7a36ce69b08100ff728e96e27445cef3b3c"
             ],
             "index": "pypi",
-            "version": "==0.600"
+            "version": "==0.620"
         },
         "nodeenv": {
             "hashes": [
-                "sha256:dd0a34001090ff042cfdb4b0c8d6a6f7ec9baa49733f00b695bb8a8b4700ba6c"
+                "sha256:0611c726af1b252908646787f4d49811aa69cd92ec19644ded06ad9d3162f88e"
             ],
-            "version": "==1.3.0"
+            "version": "==1.3.1"
         },
         "packaging": {
             "hashes": [
@@ -335,11 +332,11 @@
         },
         "pre-commit": {
             "hashes": [
-                "sha256:4e7d6fde2d22abe6823e44a447197f9f2ff25822675f5245827e15be7ea1aba7",
+                "sha256:2d57dd6b0c117ef8363233f256de8a3f26ee1c6e05ed96f9e2d9135ca5467d90",
-                "sha256:dc8dc3f293d384fcd787cfb76f142c02540741eeef0822831983c827beff87ab"
+                "sha256:9807f29320547a8a13163c1977f6765e488a9349a01431ff4fbd196ff287b51c"
             ],
             "index": "pypi",
-            "version": "==1.10.1"
+            "version": "==1.10.3"
         },
         "pycodestyle": {
             "hashes": [
@@ -371,47 +368,38 @@
         "pyparsing": {
             "hashes": [
                 "sha256:0832bcf47acd283788593e7a0f542407bd9550a55a8a8435214a1960e04bcb04",
-                "sha256:281683241b25fe9b80ec9d66017485f6deff1af5cde372469134b56ca8447a07",
-                "sha256:8f1e18d3fd36c6795bb7e02a39fd05c611ffc2596c1e0d995d34d67630426c18",
-                "sha256:9e8143a3e15c13713506886badd96ca4b579a87fbdf49e550dbfc057d6cb218e",
-                "sha256:b8b3117ed9bdf45e14dcc89345ce638ec7e0e29b2b579fa1ecf32ce45ebac8a5",
-                "sha256:e4d45427c6e20a59bf4f88c639dcc03ce30d193112047f94012102f235853a58",
                 "sha256:fee43f17a9c4087e7ed1605bd6df994c6173c1e977d7ade7b651292fab2bd010"
             ],
             "version": "==2.2.0"
         },
         "pytz": {
             "hashes": [
-                "sha256:65ae0c8101309c45772196b21b74c46b2e5d11b6275c45d251b150d5da334555",
+                "sha256:a061aa0a9e06881eb8b3b2b43f05b9439d6583c206d0a6c340ff72a7b6669053",
-                "sha256:c06425302f2cf668f1bba7a0a03f3c1d34d4ebeef2c72003da308b3947c7f749"
+                "sha256:ffb9ef1de172603304d9d2819af6f5ece76f2e85ec10692a524dd876e72bf277"
             ],
-            "version": "==2018.4"
+            "version": "==2018.5"
         },
         "pyyaml": {
             "hashes": [
-                "sha256:0c507b7f74b3d2dd4d1322ec8a94794927305ab4cebbe89cc47fe5e81541e6e8",
+                "sha256:3d7da3009c0f3e783b2c873687652d83b1bbfd5c88e9813fb7e5b03c0dd3108b",
-                "sha256:16b20e970597e051997d90dc2cddc713a2876c47e3d92d59ee198700c5427736",
+                "sha256:3ef3092145e9b70e3ddd2c7ad59bdd0252a94dfe3949721633e41344de00a6bf",
-                "sha256:3262c96a1ca437e7e4763e2843746588a965426550f3797a79fca9c6199c431f",
+                "sha256:40c71b8e076d0550b2e6380bada1f1cd1017b882f7e16f09a65be98e017f211a",
-                "sha256:326420cbb492172dec84b0f65c80942de6cedb5233c413dd824483989c000608",
+                "sha256:558dd60b890ba8fd982e05941927a3911dc409a63dcb8b634feaa0cda69330d3",
-                "sha256:4474f8ea030b5127225b8894d626bb66c01cda098d47a2b0d3429b6700af9fd8",
+                "sha256:a7c28b45d9f99102fa092bb213aa12e0aaf9a6a1f5e395d36166639c1f96c3a1",
-                "sha256:592766c6303207a20efc445587778322d7f73b161bd994f227adaa341ba212ab",
+                "sha256:aa7dd4a6a427aed7df6fb7f08a580d68d9b118d90310374716ae90b710280af1",
-                "sha256:5ac82e411044fb129bae5cfbeb3ba626acb2af31a8d17d175004b70862a741a7",
+                "sha256:bc558586e6045763782014934bfaf39d48b8ae85a2713117d16c39864085c613",
-                "sha256:5f84523c076ad14ff5e6c037fe1c89a7f73a3e04cf0377cb4d017014976433f3",
+                "sha256:d46d7982b62e0729ad0175a9bc7e10a566fc07b224d2c79fafb5e032727eaa04",
-                "sha256:827dc04b8fa7d07c44de11fabbc888e627fa8293b695e0f99cb544fdfa1bf0d1",
+                "sha256:d5eef459e30b09f5a098b9cea68bebfeb268697f78d647bd255a085371ac7f3f",
-                "sha256:b4c423ab23291d3945ac61346feeb9a0dc4184999ede5e7c43e1ffb975130ae6",
+                "sha256:e01d3203230e1786cd91ccfdc8f8454c8069c91bee3962ad93b87a4b2860f537",
-                "sha256:bc6bced57f826ca7cb5125a10b23fd0f2fff3b7c4701d64c439a300ce665fff8",
+                "sha256:e170a9e6fcfd19021dd29845af83bb79236068bf5fd4df3327c1be18182b2531"
-                "sha256:c01b880ec30b5a6e6aa67b09a2fe3fb30473008c85cd6a67359a1b15ed6d83a4",
-                "sha256:ca233c64c6e40eaa6c66ef97058cdc80e8d0157a443655baa1b2966e812807ca",
-                "sha256:e863072cdf4c72eebf179342c94e6989c67185842d9997960b3e69290b2fa269"
             ],
-            "version": "==3.12"
+            "version": "==3.13"
         },
         "readme-renderer": {
             "hashes": [
                 "sha256:422404013378f0267ee128956021a47457db8eb487908b70b8a7de5fa935781a",
                 "sha256:4547549521518be153ec428e86c0ee7c41ebd24c26b948e1d5627c94ad470808"
             ],
-            "index": "pypi",
             "version": "==21.0"
         },
         "recommonmark": {
@@ -424,16 +412,18 @@
         },
         "requests": {
             "hashes": [
-                "sha256:6a1b267aa90cac58ac3a765d067950e7dbbf75b1da07e895d1f594193a40a38b",
+                "sha256:63b52e3c866428a224f97cab011de738c36aec0185aa91cfacd418b5d58911d1",
-                "sha256:9c443e7324ba5b85070c4a818ade28bfabedf16ea10206da1132edaa6dda237e"
+                "sha256:ec22d826a36ed72a7358ff3fe56cbd4ba69dd7a6718ffd450ff0e9df7a47ce6a"
             ],
-            "version": "==2.18.4"
+            "markers": "python_version >= '2.6' and python_version != '3.2.*' and python_version < '4' and python_version != '3.3.*' and python_version != '3.0.*' and python_version != '3.1.*'",
+            "version": "==2.19.1"
         },
         "requests-toolbelt": {
             "hashes": [
                 "sha256:42c9c170abc2cacb78b8ab23ac957945c7716249206f90874651971a4acff237",
                 "sha256:f6a531936c6fa4c6cfce1b9c10d5c4f498d16528d2a54a22ca00011205a187b5"
             ],
+            "markers": "python_version >= '2.6' and python_version != '3.2.*' and python_version < '4' and python_version != '3.3.*' and python_version != '3.0.*' and python_version != '3.1.*'",
             "version": "==0.8.0"
         },
         "six": {
@@ -452,17 +442,18 @@
         },
         "sphinx": {
             "hashes": [
-                "sha256:85f7e32c8ef07f4ba5aeca728e0f7717bef0789fba8458b8d9c5c294cad134f3",
+                "sha256:217ad9ece2156ed9f8af12b5d2c82a499ddf2c70a33c5f81864a08d8c67b9efc",
-                "sha256:d45480a229edf70d84ca9fae3784162b1bc75ee47e480ffe04a4b7f21a95d76d"
+                "sha256:a765c6db1e5b62aae857697cd4402a5c1a315a7b0854bbcd0fc8cdc524da5896"
             ],
             "index": "pypi",
-            "version": "==1.7.5"
+            "version": "==1.7.6"
         },
         "sphinxcontrib-websupport": {
             "hashes": [
                 "sha256:68ca7ff70785cbe1e7bccc71a48b5b6d965d79ca50629606c7861a21b206d9dd",
                 "sha256:9de47f375baf1ea07cdb3436ff39d7a9c76042c10a769c52353ec46e4e8fc3b9"
             ],
+            "markers": "python_version != '3.2.*' and python_version >= '2.7' and python_version != '3.3.*' and python_version != '3.0.*' and python_version != '3.1.*'",
             "version": "==1.1.0"
         },
         "toml": {
@@ -477,6 +468,7 @@
                 "sha256:224291ee0d8c52d91b037fd90806f48c79bcd9994d3b0abc9e44b946a908fccd",
                 "sha256:77b8424d41b31e68f437c6dd9cd567aebc9a860507cb42fbd880a5f822d966fe"
             ],
+            "markers": "python_version >= '2.6' and python_version != '3.0.*' and python_version != '3.1.*'",
             "version": "==4.23.4"
         },
         "twine": {
@@ -490,6 +482,8 @@
         "typed-ast": {
             "hashes": [
                 "sha256:0948004fa228ae071054f5208840a1e88747a357ec1101c17217bfe99b299d58",
+                "sha256:10703d3cec8dcd9eef5a630a04056bbc898abc19bac5691612acba7d1325b66d",
+                "sha256:1f6c4bd0bdc0f14246fd41262df7dfc018d65bb05f6e16390b7ea26ca454a291",
                 "sha256:25d8feefe27eb0303b73545416b13d108c6067b846b543738a25ff304824ed9a",
                 "sha256:29464a177d56e4e055b5f7b629935af7f49c196be47528cc94e0a7bf83fbc2b9",
                 "sha256:2e214b72168ea0275efd6c884b114ab42e316de3ffa125b267e732ed2abda892",
@@ -501,6 +495,9 @@
                 "sha256:6de012d2b166fe7a4cdf505eee3aaa12192f7ba365beeefaca4ec10e31241a85",
                 "sha256:79b91ebe5a28d349b6d0d323023350133e927b4de5b651a8aa2db69c761420c6",
                 "sha256:8550177fa5d4c1f09b5e5f524411c44633c80ec69b24e0e98906dd761941ca46",
+                "sha256:898f818399cafcdb93cbbe15fc83a33d05f18e29fb498ddc09b0214cdfc7cd51",
+                "sha256:94b091dc0f19291adcb279a108f5d38de2430411068b219f41b343c03b28fb1f",
+                "sha256:a26863198902cda15ab4503991e8cf1ca874219e0118cbf07c126bce7c4db129",
                 "sha256:a8034021801bc0440f2e027c354b4eafd95891b573e12ff0418dec385c76785c",
                 "sha256:bc978ac17468fe868ee589c795d06777f75496b1ed576d308002c8a5756fb9ea",
                 "sha256:c05b41bc1deade9f90ddc5d988fe506208019ebba9f2578c622516fd201f5863",
@@ -512,16 +509,18 @@
         },
         "urllib3": {
             "hashes": [
-                "sha256:06330f386d6e4b195fbfc736b297f58c5a892e4440e54d294d7004e3a9bbea1b",
+                "sha256:a68ac5e15e76e7e5dd2b8f94007233e01effe3e50e8daddf69acfd81cb686baf",
-                "sha256:cc44da8e1145637334317feebd728bd869a35285b93cbb4cca2577da7e62db4f"
+                "sha256:b5725a0bd4ba422ab0e66e89e030c806576753ea3ee08554382c14e685d117b5"
             ],
-            "version": "==1.22"
+            "markers": "python_version >= '2.6' and python_version != '3.2.*' and python_version < '4' and python_version != '3.3.*' and python_version != '3.0.*' and python_version != '3.1.*'",
+            "version": "==1.23"
         },
         "virtualenv": {
             "hashes": [
                 "sha256:2ce32cd126117ce2c539f0134eb89de91a8413a29baac49cbab3eb50e2026669",
                 "sha256:ca07b4c0b54e14a91af9f34d0919790b016923d157afda5efdde55c96718f752"
             ],
+            "markers": "python_version != '3.0.*' and python_version != '3.2.*' and python_version != '3.1.*' and python_version >= '2.7'",
             "version": "==16.0.0"
         },
         "webencodings": {

pyproject.toml

@@ -70,6 +70,6 @@ coverage = "^4.5"
 flake8 = "^3.5"
 flake8-bugbear = "^18.2"
 flake8-mypy = "^17.8"
-mypy = "^0.600"
+mypy = "^0.620"
 readme_renderer = "^21.0"
 recommonmark = "^0.4.0"

tests/test_black.py

@@ -162,7 +162,9 @@ def test_piping(self) -> None:
         source, expected = read_data("../black", data=False)
         stderrbuf = BytesIO()
         result = BlackRunner(stderrbuf).invoke(
-            black.main, ["-", "--fast", f"--line-length={ll}"], input=source
+            black.main,
+            ["-", "--fast", f"--line-length={ll}"],
+            input=BytesIO(source.encode("utf8")),
         )
         self.assertEqual(result.exit_code, 0)
         self.assertFormatEqual(expected, result.output)
@@ -179,7 +181,9 @@ def test_piping_diff(self) -> None:
         config = THIS_DIR / "data" / "empty_pyproject.toml"
         stderrbuf = BytesIO()
         args = ["-", "--fast", f"--line-length={ll}", "--diff", f"--config={config}"]
-        result = BlackRunner(stderrbuf).invoke(black.main, args, input=source)
+        result = BlackRunner(stderrbuf).invoke(
+            black.main, args, input=BytesIO(source.encode("utf8"))
+        )
         self.assertEqual(result.exit_code, 0)
         actual = diff_header.sub("[Deterministic header]", result.output)
         actual = actual.rstrip() + "\n"  # the diff output has a trailing space
@@ -877,7 +881,9 @@ def test_no_cache_when_writeback_diff(self) -> None:
     def test_no_cache_when_stdin(self) -> None:
         mode = black.FileMode.AUTO_DETECT
         with cache_dir():
-            result = CliRunner().invoke(black.main, ["-"], input="print('hello')")
+            result = CliRunner().invoke(
+                black.main, ["-"], input=BytesIO(b"print('hello')")
+            )
             self.assertEqual(result.exit_code, 0)
             cache_file = black.get_cache_file(black.DEFAULT_LINE_LENGTH, mode)
             self.assertFalse(cache_file.exists())
@@ -1035,7 +1041,9 @@ def test_multi_file_force_pyi(self) -> None:
 
     def test_pipe_force_pyi(self) -> None:
         source, expected = read_data("force_pyi")
-        result = CliRunner().invoke(black.main, ["-", "-q", "--pyi"], input=source)
+        result = CliRunner().invoke(
+            black.main, ["-", "-q", "--pyi"], input=BytesIO(source.encode("utf8"))
+        )
         self.assertEqual(result.exit_code, 0)
         actual = result.output
         self.assertFormatEqual(actual, expected)
@@ -1089,7 +1097,9 @@ def test_multi_file_force_py36(self) -> None:
 
     def test_pipe_force_py36(self) -> None:
         source, expected = read_data("force_py36")
-        result = CliRunner().invoke(black.main, ["-", "-q", "--py36"], input=source)
+        result = CliRunner().invoke(
+            black.main, ["-", "-q", "--py36"], input=BytesIO(source.encode("utf8"))
+        )
         self.assertEqual(result.exit_code, 0)
         actual = result.output
         self.assertFormatEqual(actual, expected)
@@ -1168,9 +1178,9 @@ def test_preserves_line_endings(self) -> None:
                 test_file.write_bytes(contents.encode())
                 ff(test_file, write_back=black.WriteBack.YES)
                 updated_contents: bytes = test_file.read_bytes()
-                self.assertIn(nl.encode(), updated_contents)  # type: ignore
+                self.assertIn(nl.encode(), updated_contents)
                 if nl == "\n":
-                    self.assertNotIn(b"\r\n", updated_contents)  # type: ignore
+                    self.assertNotIn(b"\r\n", updated_contents)
 
     def test_assert_equivalent_different_asts(self) -> None:
         with self.assertRaises(AssertionError):