Repository: pypa/pipenv

Issue:
"pipenv update --dry-run" resulting in error
### Issue description

When I run `pipenv update --dry-run`, I receive an exception.

### Expected result

pipenv update --dry-run show a list of outdated dependencies.

### Actual result
```
> pipenv update --dry-run
 Locking...Building requirements...
Resolving dependencies...
Success!
Building requirements...
Resolving dependencies...
Success!
Skipped Update of Package yarl: 1.4.2 installed,, 1.4.2 available.
Skipped Update of Package wrapt: 1.12.1 installed,, 1.12.1 available.
Skipped Update of Package urllib3: 1.25.9 installed,, 1.25.9 available.
Skipped Update of Package tornado: 6.0.4 installed, 6.0.4 required (Unpinned in Pipfile), 6.0.4 available.
Skipped Update of Package toml: 0.10.0 installed,, 0.10.0 available.
Skipped Update of Package slackclient: 2.5.0 installed, (Unpinned in Pipfile), 2.5.0 available.
Skipped Update of Package six: 1.14.0 installed,, 1.14.0 available.
Traceback (most recent call last):
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.752.0_x64__qbz5n2kfra8p0\lib\runpy.py", line 193, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.752.0_x64__qbz5n2kfra8p0\lib\runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\Scripts\pipenv.exe\__main__.py", line 9, in <module>
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\core.py", line 782, in main
    rv = self.invoke(ctx)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\decorators.py", line 73, in new_func
    return ctx.invoke(f, obj, *args, **kwargs)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\vendor\click\decorators.py", line 21, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\cli\command.py", line 509, in update
    do_outdated(clear=state.clear, pre=state.installstate.pre, pypi_mirror=state.pypi_mirror)
  File "C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\site-packages\pipenv\core.py", line 1845, in do_outdated
    reverse_deps = reverse_deps.get(name_in_pipfile)
AttributeError: 'NoneType' object has no attribute 'get'
```

### Steps to replicate

1. Run pipenv update --dry-run in a project with an existing Pipfile and Pipfile.lock

-------------------------------------------------------------------------------

<details><summary>$ pipenv --support</summary>

Pipenv version: `'2020.4.1b1'`

Pipenv location: `'C:\\Users\\gabri\\AppData\\Local\\Packages\\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\\LocalCache\\local-packages\\Python38\\site-packages\\pipenv'`

Python location: `'C:\\Users\\gabri\\AppData\\Local\\Microsoft\\WindowsApps\\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\\python.exe'`

Python installations found:

  - `3.8.2`: `C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.752.0_x64__qbz5n2kfra8p0\python3.8.exe`

PEP 508 Information:

```
{'implementation_name': 'cpython',
 'implementation_version': '3.8.2',
 'os_name': 'nt',
 'platform_machine': 'AMD64',
 'platform_python_implementation': 'CPython',
 'platform_release': '10',
 'platform_system': 'Windows',
 'platform_version': '10.0.18362',
 'python_full_version': '3.8.2',
 'python_version': '3.8',
 'sys_platform': 'win32'}
```

System environment variables:

  - `ALLUSERSPROFILE`
  - `APPDATA`
  - `COLUMNS`
  - `COMMONPROGRAMFILES`
  - `COMMONPROGRAMFILES(X86)`
  - `COMMONPROGRAMW6432`
  - `COMPUTERNAME`
  - `COMSPEC`
  - `DRIVERDATA`
  - `HOME`
  - `HOMEDRIVE`
  - `HOMEPATH`
  - `LOCALAPPDATA`
  - `LOGONSERVER`
  - `NUMBER_OF_PROCESSORS`
  - `ONEDRIVE`
  - `ONEDRIVECONSUMER`
  - `OS`
  - `PATH`
  - `PATHEXT`
  - `POWERSHELL_DISTRIBUTION_CHANNEL`
  - `PROCESSOR_ARCHITECTURE`
  - `PROCESSOR_IDENTIFIER`
  - `PROCESSOR_LEVEL`
  - `PROCESSOR_REVISION`
  - `PROGRAMDATA`
  - `PROGRAMFILES`
  - `PROGRAMFILES(X86)`
  - `PROGRAMW6432`
  - `PSMODULEPATH`
  - `PUBLIC`
  - `SYSTEMDRIVE`
  - `SYSTEMROOT`
  - `TEMP`
  - `TMP`
  - `USERDOMAIN`
  - `USERDOMAIN_ROAMINGPROFILE`
  - `USERNAME`
  - `USERPROFILE`
  - `WINDIR`
  - `WSLENV`
  - `WT_PROFILE_ID`
  - `WT_SESSION`
  - `PYTHONUSERBASE`
  - `PIP_DISABLE_PIP_VERSION_CHECK`
  - `PYTHONDONTWRITEBYTECODE`
  - `PIP_SHIMS_BASE_MODULE`
  - `PIP_PYTHON_PATH`
  - `PYTHONFINDER_IGNORE_UNSUPPORTED`

Pipenv╬ô├ç├┤specific environment variables:


Debug╬ô├ç├┤specific environment variables:

  - `PATH`: `C:\Program Files\PowerShell\7;C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\Program Files (x86)\Razer Chroma SDK\bin;C:\Program Files\Razer Chroma SDK\bin;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Windows\System32\OpenSSH\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files\NVIDIA Corporation\NVIDIA NvDLISR;C:\Users\gabri\AppData\Local\Microsoft\WindowsApps;C:\Users\gabri\.dotnet\tools;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\WINDOWS\System32\OpenSSH\;C:\ProgramData\ComposerSetup\bin;C:\Program Files (x86)\Intel\Intel(R) Management Engine Components\DAL;C:\Program Files\Intel\Intel(R) Management Engine Components\DAL;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Intel\WirelessCommon\;C:\bin\nodejs\;C:\Program Files\PowerShell\7\;C:\Program Files\Git\cmd;C:\Program Files\Docker\Docker\resources\bin;C:\ProgramData\DockerDesktop\version-bin;C:\Program Files\;C:\Program Files\dotnet\;C:\Program Files\PowerShell\6\;C:\Program Files\Docker\Docker\Resources\bin;C:\Program Files\Microsoft SQL Server\130\Tools\Binn\;C:\Program Files\Microsoft SQL Server\Client SDK\ODBC\170\Tools\Binn\;C:\Program Files (x86)\Microsoft SQL Server\150\DTS\Binn\;C:\Users\gabri\AppData\Local\Programs\Microsoft VS Code\bin;C:\Users\gabri\AppData\Local\Programs\Azure Data Studio\bin;C:\Users\gabri\AppData\Roaming\npm;C:\Users\gabri\AppData\Roaming\Composer\vendor\bin;C:\Users\gabri\AppData\Roaming\devspace;C:\Users\gabri\composer;C:\bin\go\bin;C:\bin\php\7.4;C:\Users\gabri\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0\LocalCache\local-packages\Python38\Scripts`


---------------------------

Contents of `Pipfile` ('C:\\Users\\gabri\\Code\\gateway\\Pipfile'):

```toml
[[source]]
name = "pypi"
url = "https://pypi.org/simple"
verify_ssl = true

[dev-packages]
pylint = "*"

[packages]
tornado = "*"
slackclient = "*"
requests = "*"
Jinja2 = "*"
idna_ssl = "*"
html-slacker = "*"

[requires]
python_version = "3.8"

```


Contents of `Pipfile.lock` ('C:\\Users\\gabri\\Code\\gateway\\Pipfile.lock'):

```json
{
    "_meta": {
        "hash": {
            "sha256": "73ddf729e230ef3844ecd18f48b0ec39ab5a996f44a764166203f8667b4f9332"
        },
        "pipfile-spec": 6,
        "requires": {
            "python_version": "3.8"
        },
        "sources": [
            {
                "name": "pypi",
                "url": "https://pypi.org/simple",
                "verify_ssl": true
            }
        ]
    },
    "default": {
        "aiohttp": {
            "hashes": [
                "sha256:1e984191d1ec186881ffaed4581092ba04f7c61582a177b187d3a2f07ed9719e",
                "sha256:259ab809ff0727d0e834ac5e8a283dc5e3e0ecc30c4d80b3cd17a4139ce1f326",
                "sha256:2f4d1a4fdce595c947162333353d4a44952a724fba9ca3205a3df99a33d1307a",
                "sha256:32e5f3b7e511aa850829fbe5aa32eb455e5534eaa4b1ce93231d00e2f76e5654",
                "sha256:344c780466b73095a72c616fac5ea9c4665add7fc129f285fbdbca3cccf4612a",
                "sha256:460bd4237d2dbecc3b5ed57e122992f60188afe46e7319116da5eb8a9dfedba4",
                "sha256:4c6efd824d44ae697814a2a85604d8e992b875462c6655da161ff18fd4f29f17",
                "sha256:50aaad128e6ac62e7bf7bd1f0c0a24bc968a0c0590a726d5a955af193544bcec",
                "sha256:6206a135d072f88da3e71cc501c59d5abffa9d0bb43269a6dcd28d66bfafdbdd",
                "sha256:65f31b622af739a802ca6fd1a3076fd0ae523f8485c52924a89561ba10c49b48",
                "sha256:ae55bac364c405caa23a4f2d6cfecc6a0daada500274ffca4a9230e7129eac59",
                "sha256:b778ce0c909a2653741cb4b1ac7015b5c130ab9c897611df43ae6a58523cb965"
            ],
            "markers": "python_full_version >= '3.5.3'",
            "version": "==3.6.2"
        },
        "async-timeout": {
            "hashes": [
                "sha256:0c3c816a028d47f659d6ff5c745cb2acf1f966da1fe5c19c77a70282b25f4c5f",
                "sha256:4291ca197d287d274d0b6cb5d6f8f8f82d434ed288f962539ff18cc9012f9ea3"
            ],
            "markers": "python_full_version >= '3.5.3'",
            "version": "==3.0.1"
        },
        "attrs": {
            "hashes": [
                "sha256:08a96c641c3a74e44eb59afb61a24f2cb9f4d7188748e76ba4bb5edfa3cb7d1c",
                "sha256:f7b7ce16570fe9965acd6d30101a28f62fb4a7f9e926b3bbc9b61f8b04247e72"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==19.3.0"
        },
        "certifi": {
            "hashes": [
                "sha256:1d987a998c75633c40847cc966fcf5904906c920a7f17ef374f5aa4282abd304",
                "sha256:51fcb31174be6e6664c5f69e3e1691a2d72a1a12e90f872cbdb1567eb47b6519"
            ],
            "version": "==2020.4.5.1"
        },
        "chardet": {
            "hashes": [
                "sha256:84ab92ed1c4d4f16916e05906b6b75a6c0fb5db821cc65e70cbd64a3e2a5eaae",
                "sha256:fc323ffcaeaed0e0a02bf4d117757b98aed530d9ed4531e3e15460124c106691"
            ],
            "version": "==3.0.4"
        },
        "html-slacker": {
            "hashes": [
                "sha256:22dd8847d01e8516e75d8f6af8572356568cd439134b846b00e62dd1e4df4ee1",
                "sha256:4458b7c18eb45fda04433364fa065f0107599516fc3cb4ee59de01256821ce7f"
            ],
            "index": "pypi",
            "version": "==0.1.6"
        },
        "idna": {
            "hashes": [
                "sha256:7588d1c14ae4c77d74036e8c22ff447b26d0fde8f007354fd48a7814db15b7cb",
                "sha256:a068a21ceac8a4d63dbfd964670474107f541babbd2250d61922f029858365fa"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==2.9"
        },
        "idna-ssl": {
            "hashes": [
                "sha256:a933e3bb13da54383f9e8f35dc4f9cb9eb9b3b78c6b36f311254d6d0d92c6c7c"
            ],
            "index": "pypi",
            "version": "==1.1.0"
        },
        "jinja2": {
            "hashes": [
                "sha256:89aab215427ef59c34ad58735269eb58b1a5808103067f7bb9d5836c651b3bb0",
                "sha256:f0a4641d3cf955324a89c04f3d94663aa4d638abe8f733ecd3582848e1c37035"
            ],
            "index": "pypi",
            "version": "==2.11.2"
        },
        "markupsafe": {
            "hashes": [
                "sha256:00bc623926325b26bb9605ae9eae8a215691f33cae5df11ca5424f06f2d1f473",
                "sha256:09027a7803a62ca78792ad89403b1b7a73a01c8cb65909cd876f7fcebd79b161",
                "sha256:09c4b7f37d6c648cb13f9230d847adf22f8171b1ccc4d5682398e77f40309235",
                "sha256:1027c282dad077d0bae18be6794e6b6b8c91d58ed8a8d89a89d59693b9131db5",
                "sha256:13d3144e1e340870b25e7b10b98d779608c02016d5184cfb9927a9f10c689f42",
                "sha256:24982cc2533820871eba85ba648cd53d8623687ff11cbb805be4ff7b4c971aff",
                "sha256:29872e92839765e546828bb7754a68c418d927cd064fd4708fab9fe9c8bb116b",
                "sha256:43a55c2930bbc139570ac2452adf3d70cdbb3cfe5912c71cdce1c2c6bbd9c5d1",
                "sha256:46c99d2de99945ec5cb54f23c8cd5689f6d7177305ebff350a58ce5f8de1669e",
                "sha256:500d4957e52ddc3351cabf489e79c91c17f6e0899158447047588650b5e69183",
                "sha256:535f6fc4d397c1563d08b88e485c3496cf5784e927af890fb3c3aac7f933ec66",
                "sha256:596510de112c685489095da617b5bcbbac7dd6384aeebeda4df6025d0256a81b",
                "sha256:62fe6c95e3ec8a7fad637b7f3d372c15ec1caa01ab47926cfdf7a75b40e0eac1",
                "sha256:6788b695d50a51edb699cb55e35487e430fa21f1ed838122d722e0ff0ac5ba15",
                "sha256:6dd73240d2af64df90aa7c4e7481e23825ea70af4b4922f8ede5b9e35f78a3b1",
                "sha256:717ba8fe3ae9cc0006d7c451f0bb265ee07739daf76355d06366154ee68d221e",
                "sha256:79855e1c5b8da654cf486b830bd42c06e8780cea587384cf6545b7d9ac013a0b",
                "sha256:7c1699dfe0cf8ff607dbdcc1e9b9af1755371f92a68f706051cc8c37d447c905",
                "sha256:88e5fcfb52ee7b911e8bb6d6aa2fd21fbecc674eadd44118a9cc3863f938e735",
                "sha256:8defac2f2ccd6805ebf65f5eeb132adcf2ab57aa11fdf4c0dd5169a004710e7d",
                "sha256:98c7086708b163d425c67c7a91bad6e466bb99d797aa64f965e9d25c12111a5e",
                "sha256:9add70b36c5666a2ed02b43b335fe19002ee5235efd4b8a89bfcf9005bebac0d",
                "sha256:9bf40443012702a1d2070043cb6291650a0841ece432556f784f004937f0f32c",
                "sha256:ade5e387d2ad0d7ebf59146cc00c8044acbd863725f887353a10df825fc8ae21",
                "sha256:b00c1de48212e4cc9603895652c5c410df699856a2853135b3967591e4beebc2",
                "sha256:b1282f8c00509d99fef04d8ba936b156d419be841854fe901d8ae224c59f0be5",
                "sha256:b2051432115498d3562c084a49bba65d97cf251f5a331c64a12ee7e04dacc51b",
                "sha256:ba59edeaa2fc6114428f1637ffff42da1e311e29382d81b339c1817d37ec93c6",
                "sha256:c8716a48d94b06bb3b2524c2b77e055fb313aeb4ea620c8dd03a105574ba704f",
                "sha256:cd5df75523866410809ca100dc9681e301e3c27567cf498077e8551b6d20e42f",
                "sha256:cdb132fc825c38e1aeec2c8aa9338310d29d337bebbd7baa06889d09a60a1fa2",
                "sha256:e249096428b3ae81b08327a63a485ad0878de3fb939049038579ac0ef61e17e7",
                "sha256:e8313f01ba26fbbe36c7be1966a7b7424942f670f38e666995b88d012765b9be"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==1.1.1"
        },
        "multidict": {
            "hashes": [
                "sha256:317f96bc0950d249e96d8d29ab556d01dd38888fbe68324f46fd834b430169f1",
                "sha256:42f56542166040b4474c0c608ed051732033cd821126493cf25b6c276df7dd35",
                "sha256:4b7df040fb5fe826d689204f9b544af469593fb3ff3a069a6ad3409f742f5928",
                "sha256:544fae9261232a97102e27a926019100a9db75bec7b37feedd74b3aa82f29969",
                "sha256:620b37c3fea181dab09267cd5a84b0f23fa043beb8bc50d8474dd9694de1fa6e",
                "sha256:6e6fef114741c4d7ca46da8449038ec8b1e880bbe68674c01ceeb1ac8a648e78",
                "sha256:7774e9f6c9af3f12f296131453f7b81dabb7ebdb948483362f5afcaac8a826f1",
                "sha256:85cb26c38c96f76b7ff38b86c9d560dea10cf3459bb5f4caf72fc1bb932c7136",
                "sha256:a326f4240123a2ac66bb163eeba99578e9d63a8654a59f4688a79198f9aa10f8",
                "sha256:ae402f43604e3b2bc41e8ea8b8526c7fa7139ed76b0d64fc48e28125925275b2",
                "sha256:aee283c49601fa4c13adc64c09c978838a7e812f85377ae130a24d7198c0331e",
                "sha256:b51249fdd2923739cd3efc95a3d6c363b67bbf779208e9f37fd5e68540d1a4d4",
                "sha256:bb519becc46275c594410c6c28a8a0adc66fe24fef154a9addea54c1adb006f5",
                "sha256:c2c37185fb0af79d5c117b8d2764f4321eeb12ba8c141a95d0aa8c2c1d0a11dd",
                "sha256:dc561313279f9d05a3d0ffa89cd15ae477528ea37aa9795c4654588a3287a9ab",
                "sha256:e439c9a10a95cb32abd708bb8be83b2134fa93790a4fb0535ca36db3dda94d20",
                "sha256:fc3b4adc2ee8474cb3cd2a155305d5f8eda0a9c91320f83e55748e1fcb68f8e3"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==4.7.5"
        },
        "requests": {
            "hashes": [
                "sha256:43999036bfa82904b6af1d99e4882b560e5e2c68e5c4b0aa03b655f3d7d73fee",
                "sha256:b3f43d496c6daba4493e7c431722aeb7dbc6288f52a6e04e7b6023b0247817e6"
            ],
            "index": "pypi",
            "version": "==2.23.0"
        },
        "slackclient": {
            "hashes": [
                "sha256:16ebbfa1c34374fa8c508d0c8e5c670e41bba4a3f62c469ab1ee1b8225a939fa",
                "sha256:d37e4f91be9cf9d5c1a1698f44a37671fc92823ff01146cd827415f35fabe636"
            ],
            "index": "pypi",
            "version": "==2.5.0"
        },
        "tornado": {
            "hashes": [
                "sha256:0fe2d45ba43b00a41cd73f8be321a44936dc1aba233dee979f17a042b83eb6dc",
                "sha256:22aed82c2ea340c3771e3babc5ef220272f6fd06b5108a53b4976d0d722bcd52",
                "sha256:2c027eb2a393d964b22b5c154d1a23a5f8727db6fda837118a776b29e2b8ebc6",
                "sha256:5217e601700f24e966ddab689f90b7ea4bd91ff3357c3600fa1045e26d68e55d",
                "sha256:5618f72e947533832cbc3dec54e1dffc1747a5cb17d1fd91577ed14fa0dc081b",
                "sha256:5f6a07e62e799be5d2330e68d808c8ac41d4a259b9cea61da4101b83cb5dc673",
                "sha256:c58d56003daf1b616336781b26d184023ea4af13ae143d9dda65e31e534940b9",
                "sha256:c952975c8ba74f546ae6de2e226ab3cc3cc11ae47baf607459a6728585bb542a",
                "sha256:c98232a3ac391f5faea6821b53db8db461157baa788f5d6222a193e9456e1740"
            ],
            "index": "pypi",
            "version": "==6.0.4"
        },
        "urllib3": {
            "hashes": [
                "sha256:3018294ebefce6572a474f0604c2021e33b3fd8006ecd11d62107a5d2a963527",
                "sha256:88206b0eb87e6d677d424843ac5209e3fb9d0190d0ee169599165ec25e9d9115"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3' and python_version < '4'",
            "version": "==1.25.9"
        },
        "yarl": {
            "hashes": [
                "sha256:0c2ab325d33f1b824734b3ef51d4d54a54e0e7a23d13b86974507602334c2cce",
                "sha256:0ca2f395591bbd85ddd50a82eb1fde9c1066fafe888c5c7cc1d810cf03fd3cc6",
                "sha256:2098a4b4b9d75ee352807a95cdf5f10180db903bc5b7270715c6bbe2551f64ce",
                "sha256:25e66e5e2007c7a39541ca13b559cd8ebc2ad8fe00ea94a2aad28a9b1e44e5ae",
                "sha256:26d7c90cb04dee1665282a5d1a998defc1a9e012fdca0f33396f81508f49696d",
                "sha256:308b98b0c8cd1dfef1a0311dc5e38ae8f9b58349226aa0533f15a16717ad702f",
                "sha256:3ce3d4f7c6b69c4e4f0704b32eca8123b9c58ae91af740481aa57d7857b5e41b",
                "sha256:58cd9c469eced558cd81aa3f484b2924e8897049e06889e8ff2510435b7ef74b",
                "sha256:5b10eb0e7f044cf0b035112446b26a3a2946bca9d7d7edb5e54a2ad2f6652abb",
                "sha256:6faa19d3824c21bcbfdfce5171e193c8b4ddafdf0ac3f129ccf0cdfcb083e462",
                "sha256:944494be42fa630134bf907714d40207e646fd5a94423c90d5b514f7b0713fea",
                "sha256:a161de7e50224e8e3de6e184707476b5a989037dcb24292b391a3d66ff158e70",
                "sha256:a4844ebb2be14768f7994f2017f70aca39d658a96c786211be5ddbe1c68794c1",
                "sha256:c2b509ac3d4b988ae8769901c66345425e361d518aecbe4acbfc2567e416626a",
                "sha256:c9959d49a77b0e07559e579f38b2f3711c2b8716b8410b320bf9713013215a1b",
                "sha256:d8cdee92bc930d8b09d8bd2043cedd544d9c8bd7436a77678dd602467a993080",
                "sha256:e15199cdb423316e15f108f51249e44eb156ae5dba232cb73be555324a1d49c2"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==1.4.2"
        }
    },
    "develop": {
        "astroid": {
            "hashes": [
                "sha256:29fa5d46a2404d01c834fcb802a3943685f1fc538eb2a02a161349f5505ac196",
                "sha256:2fecea42b20abb1922ed65c7b5be27edfba97211b04b2b6abc6a43549a024ea6"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==2.4.0"
        },
        "colorama": {
            "hashes": [
                "sha256:7d73d2a99753107a36ac6b455ee49046802e59d9d076ef8e47b61499fa29afff",
                "sha256:e96da0d330793e2cb9485e9ddfd918d456036c7149416295932478192f4436a1"
            ],
            "markers": "sys_platform == 'win32'",
            "version": "==0.4.3"
        },
        "isort": {
            "hashes": [
                "sha256:54da7e92468955c4fceacd0c86bd0ec997b0e1ee80d97f67c35a78b719dccab1",
                "sha256:6e811fcb295968434526407adb8796944f1988c5b65e8139058f2014cbe100fd"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==4.3.21"
        },
        "lazy-object-proxy": {
            "hashes": [
                "sha256:0c4b206227a8097f05c4dbdd323c50edf81f15db3b8dc064d08c62d37e1a504d",
                "sha256:194d092e6f246b906e8f70884e620e459fc54db3259e60cf69a4d66c3fda3449",
                "sha256:1be7e4c9f96948003609aa6c974ae59830a6baecc5376c25c92d7d697e684c08",
                "sha256:4677f594e474c91da97f489fea5b7daa17b5517190899cf213697e48d3902f5a",
                "sha256:48dab84ebd4831077b150572aec802f303117c8cc5c871e182447281ebf3ac50",
                "sha256:5541cada25cd173702dbd99f8e22434105456314462326f06dba3e180f203dfd",
                "sha256:59f79fef100b09564bc2df42ea2d8d21a64fdcda64979c0fa3db7bdaabaf6239",
                "sha256:8d859b89baf8ef7f8bc6b00aa20316483d67f0b1cbf422f5b4dc56701c8f2ffb",
                "sha256:9254f4358b9b541e3441b007a0ea0764b9d056afdeafc1a5569eee1cc6c1b9ea",
                "sha256:9651375199045a358eb6741df3e02a651e0330be090b3bc79f6d0de31a80ec3e",
                "sha256:97bb5884f6f1cdce0099f86b907aa41c970c3c672ac8b9c8352789e103cf3156",
                "sha256:9b15f3f4c0f35727d3a0fba4b770b3c4ebbb1fa907dbcc046a1d2799f3edd142",
                "sha256:a2238e9d1bb71a56cd710611a1614d1194dc10a175c1e08d75e1a7bcc250d442",
                "sha256:a6ae12d08c0bf9909ce12385803a543bfe99b95fe01e752536a60af2b7797c62",
                "sha256:ca0a928a3ddbc5725be2dd1cf895ec0a254798915fb3a36af0964a0a4149e3db",
                "sha256:cb2c7c57005a6804ab66f106ceb8482da55f5314b7fcb06551db1edae4ad1531",
                "sha256:d74bb8693bf9cf75ac3b47a54d716bbb1a92648d5f781fc799347cfc95952383",
                "sha256:d945239a5639b3ff35b70a88c5f2f491913eb94871780ebfabb2568bd58afc5a",
                "sha256:eba7011090323c1dadf18b3b689845fd96a61ba0a1dfbd7f24b921398affc357",
                "sha256:efa1909120ce98bbb3777e8b6f92237f5d5c8ea6758efea36a473e1d38f7d3e4",
                "sha256:f3900e8a5de27447acbf900b4750b0ddfd7ec1ea7fbaf11dfa911141bc522af0"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==1.4.3"
        },
        "mccabe": {
            "hashes": [
                "sha256:ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42",
                "sha256:dd8d182285a0fe56bace7f45b5e7d1a6ebcbf524e8f3bd87eb0f125271b8831f"
            ],
            "version": "==0.6.1"
        },
        "pylint": {
            "hashes": [
                "sha256:588e114e3f9a1630428c35b7dd1c82c1c93e1b0e78ee312ae4724c5e1a1e0245",
                "sha256:bd556ba95a4cf55a1fc0004c00cf4560b1e70598a54a74c6904d933c8f3bd5a8"
            ],
            "index": "pypi",
            "version": "==2.5.0"
        },
        "six": {
            "hashes": [
                "sha256:236bdbdce46e6e6a3d61a337c0f8b763ca1e8717c03b369e87a7ec7ce1319c0a",
                "sha256:8f3cd2e254d8f793e7f3d6d9df77b92252b52637291d0f0da013c76ea2724b6c"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==1.14.0"
        },
        "toml": {
            "hashes": [
                "sha256:229f81c57791a41d65e399fc06bf0848bab550a9dfd5ed66df18ce5f05e73d5c",
                "sha256:235682dd292d5899d361a811df37e04a8828a5b1da3115886b73cf81ebc9100e",
                "sha256:f1db651f9657708513243e61e6cc67d101a39bad662eaa9b5546f789338e07a3"
            ],
            "version": "==0.10.0"
        },
        "wrapt": {
            "hashes": [
                "sha256:b62ffa81fb85f4332a4f609cab4ac40709470da05643a082ec1eb88e6d9b97d7"
            ],
            "version": "==1.12.1"
        }
    }
}

```
</details>



Discussion:
I could also replicate this in my Linux/Ubuntu WSL environment:

```
> pipenv update --dry-run
Building requirements...
Resolving dependencies...
✔ Success!
Building requirements...
Resolving dependencies...
✔ Success!
Skipped Update of Package yarl: 1.4.2 installed,, 1.4.2 available.
Skipped Update of Package typed-ast: 1.4.1 installed,, 1.4.1 available.
Skipped Update of Package tornado: 6.0.4 installed, 6.0.4 required (Unpinned in Pipfile), 6.0.4 available.
Skipped Update of Package slackclient: 2.5.0 installed, (Unpinned in Pipfile), 2.5.0 available.
Skipped Update of Package six: 1.14.0 installed,, 1.14.0 available.
Traceback (most recent call last):
  File "/home/gmsantos/.local/bin/pipenv", line 8, in <module>
    sys.exit(cli())
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 782, in main
    rv = self.invoke(ctx)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/decorators.py", line 73, in new_func
    return ctx.invoke(f, obj, *args, **kwargs)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/vendor/click/decorators.py", line 21, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/cli/command.py", line 509, in update
    do_outdated(clear=state.clear, pre=state.installstate.pre, pypi_mirror=state.pypi_mirror)
  File "/home/gmsantos/.local/lib/python3.6/site-packages/pipenv/core.py", line 1845, in do_outdated
    reverse_deps = reverse_deps.get(name_in_pipfile)
AttributeError: 'NoneType' object has no attribute 'get'
```

<details><summary>$ pipenv --support</summary>

Pipenv version: `'2020.4.1b1'`

Pipenv location: `'/home/gmsantos/.local/lib/python3.6/site-packages/pipenv'`

Python location: `'/usr/bin/python3'`

Python installations found:

  - `3.6.9`: `/usr/bin/python3`
  - `3.6.9`: `/usr/bin/python3.6`
  - `3.6.9`: `/usr/bin/python3.6m`
  - `2.7.17`: `/usr/bin/python2`
  - `2.7.17`: `/usr/bin/python2.7`

PEP 508 Information:

```
{'implementation_name': 'cpython',
 'implementation_version': '3.6.9',
 'os_name': 'posix',
 'platform_machine': 'x86_64',
 'platform_python_implementation': 'CPython',
 'platform_release': '4.4.0-18362-Microsoft',
 'platform_system': 'Linux',
 'platform_version': '#476-Microsoft Fri Nov 01 16:53:00 PST 2019',
 'python_full_version': '3.6.9',
 'python_version': '3.6',
 'sys_platform': 'linux'}
```

System environment variables:

  - `HOSTTYPE`
  - `LANG`
  - `PATH`
  - `TERM`
  - `WSLENV`
  - `WT_SESSION`
  - `WT_PROFILE_ID`
  - `NAME`
  - `HOME`
  - `USER`
  - `LOGNAME`
  - `SHELL`
  - `WSL_DISTRO_NAME`
  - `SHLVL`
  - `PWD`
  - `OLDPWD`
  - `ZSH`
  - `PAGER`
  - `LESS`
  - `LSCOLORS`
  - `LS_COLORS`
  - `_`
  - `PIP_DISABLE_PIP_VERSION_CHECK`
  - `PYTHONDONTWRITEBYTECODE`
  - `PIP_SHIMS_BASE_MODULE`
  - `PIP_PYTHON_PATH`
  - `PYTHONFINDER_IGNORE_UNSUPPORTED`

Pipenv–specific environment variables:


Debug–specific environment variables:

  - `PATH`: `/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/mnt/c/Program Files (x86)/Common Files/Oracle/Java/javapath:/mnt/c/Program Files (x86)/Razer Chroma SDK/bin:/mnt/c/Program Files/Razer Chroma SDK/bin:/mnt/c/Windows/system32:/mnt/c/Windows:/mnt/c/Windows/System32/Wbem:/mnt/c/Windows/System32/WindowsPowerShell/v1.0/:/mnt/c/Windows/System32/OpenSSH/:/mnt/c/Program Files (x86)/NVIDIA Corporation/PhysX/Common:/mnt/c/Program Files/NVIDIA Corporation/NVIDIA NvDLISR:/mnt/c/Users/gabri/AppData/Local/Microsoft/WindowsApps:/mnt/c/Users/gabri/.dotnet/tools:/mnt/c/WINDOWS/system32:/mnt/c/WINDOWS:/mnt/c/WINDOWS/System32/Wbem:/mnt/c/WINDOWS/System32/WindowsPowerShell/v1.0/:/mnt/c/WINDOWS/System32/OpenSSH/:/mnt/c/ProgramData/ComposerSetup/bin:/mnt/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/DAL:/mnt/c/Program Files/Intel/Intel(R) Management Engine Components/DAL:/mnt/c/Program Files/Intel/WiFi/bin/:/mnt/c/Program Files/Common Files/Intel/WirelessCommon/:/mnt/c/bin/nodejs/:/mnt/c/Program Files/PowerShell/7/:/mnt/c/Program Files/Git/cmd:/mnt/c/Program Files/Docker/Docker/resources/bin:/mnt/c/ProgramData/DockerDesktop/version-bin:/mnt/c/Program Files/:/mnt/c/Program Files/dotnet/:/mnt/c/Program Files/PowerShell/6/:/mnt/c/Program Files/Docker/Docker/Resources/bin:/mnt/c/Program Files/Microsoft SQL Server/130/Tools/Binn/:/mnt/c/Program Files/Microsoft SQL Server/Client SDK/ODBC/170/Tools/Binn/:/mnt/c/Program Files (x86)/Microsoft SQL Server/150/DTS/Binn/:/mnt/c/Users/gabri/AppData/Local/Programs/Microsoft VS Code/bin:/mnt/c/Users/gabri/AppData/Local/Programs/Azure Data Studio/bin:/mnt/c/Users/gabri/AppData/Roaming/npm:/mnt/c/Users/gabri/AppData/Roaming/Composer/vendor/bin:/mnt/c/Users/gabri/AppData/Roaming/devspace:/mnt/c/Users/gabri/composer:/mnt/c/bin/go/bin:/mnt/c/bin/php/7.4:/mnt/c/Users/gabri/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.8_qbz5n2kfra8p0/LocalCache/local-packages/Python38/Scripts:/home/gmsantos/.local/bin`
  - `SHELL`: `/usr/bin/zsh`
  - `LANG`: `C.UTF-8`
  - `PWD`: `/home/gmsantos/Code/dati-gateway`


---------------------------

Contents of `Pipfile` ('/home/gmsantos/Code/dati-gateway/Pipfile'):

```toml
[[source]]
name = "pypi"
url = "https://pypi.org/simple"
verify_ssl = true

[dev-packages]
pylint = "*"

[packages]
tornado = "*"
slackclient = "*"
requests = "*"
Jinja2 = "*"
idna_ssl = "*"
html-slacker = "*"

[requires]
python_version = "3.6"

```


Contents of `Pipfile.lock` ('/home/gmsantos/Code/dati-gateway/Pipfile.lock'):

```json
{
    "_meta": {
        "hash": {
            "sha256": "73ddf729e230ef3844ecd18f48b0ec39ab5a996f44a764166203f8667b4f9332"
        },
        "pipfile-spec": 6,
        "requires": {
            "python_version": "3.8"
        },
        "sources": [
            {
                "name": "pypi",
                "url": "https://pypi.org/simple",
                "verify_ssl": true
            }
        ]
    },
    "default": {
        "aiohttp": {
            "hashes": [
                "sha256:1e984191d1ec186881ffaed4581092ba04f7c61582a177b187d3a2f07ed9719e",
                "sha256:259ab809ff0727d0e834ac5e8a283dc5e3e0ecc30c4d80b3cd17a4139ce1f326",
                "sha256:2f4d1a4fdce595c947162333353d4a44952a724fba9ca3205a3df99a33d1307a",
                "sha256:32e5f3b7e511aa850829fbe5aa32eb455e5534eaa4b1ce93231d00e2f76e5654",
                "sha256:344c780466b73095a72c616fac5ea9c4665add7fc129f285fbdbca3cccf4612a",
                "sha256:460bd4237d2dbecc3b5ed57e122992f60188afe46e7319116da5eb8a9dfedba4",
                "sha256:4c6efd824d44ae697814a2a85604d8e992b875462c6655da161ff18fd4f29f17",
                "sha256:50aaad128e6ac62e7bf7bd1f0c0a24bc968a0c0590a726d5a955af193544bcec",
                "sha256:6206a135d072f88da3e71cc501c59d5abffa9d0bb43269a6dcd28d66bfafdbdd",
                "sha256:65f31b622af739a802ca6fd1a3076fd0ae523f8485c52924a89561ba10c49b48",
                "sha256:ae55bac364c405caa23a4f2d6cfecc6a0daada500274ffca4a9230e7129eac59",
                "sha256:b778ce0c909a2653741cb4b1ac7015b5c130ab9c897611df43ae6a58523cb965"
            ],
            "markers": "python_full_version >= '3.5.3'",
            "version": "==3.6.2"
        },
        "async-timeout": {
            "hashes": [
                "sha256:0c3c816a028d47f659d6ff5c745cb2acf1f966da1fe5c19c77a70282b25f4c5f",
                "sha256:4291ca197d287d274d0b6cb5d6f8f8f82d434ed288f962539ff18cc9012f9ea3"
            ],
            "markers": "python_full_version >= '3.5.3'",
            "version": "==3.0.1"
        },
        "attrs": {
            "hashes": [
                "sha256:08a96c641c3a74e44eb59afb61a24f2cb9f4d7188748e76ba4bb5edfa3cb7d1c",
                "sha256:f7b7ce16570fe9965acd6d30101a28f62fb4a7f9e926b3bbc9b61f8b04247e72"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==19.3.0"
        },
        "certifi": {
            "hashes": [
                "sha256:1d987a998c75633c40847cc966fcf5904906c920a7f17ef374f5aa4282abd304",
                "sha256:51fcb31174be6e6664c5f69e3e1691a2d72a1a12e90f872cbdb1567eb47b6519"
            ],
            "version": "==2020.4.5.1"
        },
        "chardet": {
            "hashes": [
                "sha256:84ab92ed1c4d4f16916e05906b6b75a6c0fb5db821cc65e70cbd64a3e2a5eaae",
                "sha256:fc323ffcaeaed0e0a02bf4d117757b98aed530d9ed4531e3e15460124c106691"
            ],
            "version": "==3.0.4"
        },
        "html-slacker": {
            "hashes": [
                "sha256:22dd8847d01e8516e75d8f6af8572356568cd439134b846b00e62dd1e4df4ee1",
                "sha256:4458b7c18eb45fda04433364fa065f0107599516fc3cb4ee59de01256821ce7f"
            ],
            "index": "pypi",
            "version": "==0.1.6"
        },
        "idna": {
            "hashes": [
                "sha256:7588d1c14ae4c77d74036e8c22ff447b26d0fde8f007354fd48a7814db15b7cb",
                "sha256:a068a21ceac8a4d63dbfd964670474107f541babbd2250d61922f029858365fa"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==2.9"
        },
        "idna-ssl": {
            "hashes": [
                "sha256:a933e3bb13da54383f9e8f35dc4f9cb9eb9b3b78c6b36f311254d6d0d92c6c7c"
            ],
            "index": "pypi",
            "version": "==1.1.0"
        },
        "jinja2": {
            "hashes": [
                "sha256:89aab215427ef59c34ad58735269eb58b1a5808103067f7bb9d5836c651b3bb0",
                "sha256:f0a4641d3cf955324a89c04f3d94663aa4d638abe8f733ecd3582848e1c37035"
            ],
            "index": "pypi",
            "version": "==2.11.2"
        },
        "markupsafe": {
            "hashes": [
                "sha256:00bc623926325b26bb9605ae9eae8a215691f33cae5df11ca5424f06f2d1f473",
                "sha256:09027a7803a62ca78792ad89403b1b7a73a01c8cb65909cd876f7fcebd79b161",
                "sha256:09c4b7f37d6c648cb13f9230d847adf22f8171b1ccc4d5682398e77f40309235",
                "sha256:1027c282dad077d0bae18be6794e6b6b8c91d58ed8a8d89a89d59693b9131db5",
                "sha256:13d3144e1e340870b25e7b10b98d779608c02016d5184cfb9927a9f10c689f42",
                "sha256:24982cc2533820871eba85ba648cd53d8623687ff11cbb805be4ff7b4c971aff",
                "sha256:29872e92839765e546828bb7754a68c418d927cd064fd4708fab9fe9c8bb116b",
                "sha256:43a55c2930bbc139570ac2452adf3d70cdbb3cfe5912c71cdce1c2c6bbd9c5d1",
                "sha256:46c99d2de99945ec5cb54f23c8cd5689f6d7177305ebff350a58ce5f8de1669e",
                "sha256:500d4957e52ddc3351cabf489e79c91c17f6e0899158447047588650b5e69183",
                "sha256:535f6fc4d397c1563d08b88e485c3496cf5784e927af890fb3c3aac7f933ec66",
                "sha256:596510de112c685489095da617b5bcbbac7dd6384aeebeda4df6025d0256a81b",
                "sha256:62fe6c95e3ec8a7fad637b7f3d372c15ec1caa01ab47926cfdf7a75b40e0eac1",
                "sha256:6788b695d50a51edb699cb55e35487e430fa21f1ed838122d722e0ff0ac5ba15",
                "sha256:6dd73240d2af64df90aa7c4e7481e23825ea70af4b4922f8ede5b9e35f78a3b1",
                "sha256:717ba8fe3ae9cc0006d7c451f0bb265ee07739daf76355d06366154ee68d221e",
                "sha256:79855e1c5b8da654cf486b830bd42c06e8780cea587384cf6545b7d9ac013a0b",
                "sha256:7c1699dfe0cf8ff607dbdcc1e9b9af1755371f92a68f706051cc8c37d447c905",
                "sha256:88e5fcfb52ee7b911e8bb6d6aa2fd21fbecc674eadd44118a9cc3863f938e735",
                "sha256:8defac2f2ccd6805ebf65f5eeb132adcf2ab57aa11fdf4c0dd5169a004710e7d",
                "sha256:98c7086708b163d425c67c7a91bad6e466bb99d797aa64f965e9d25c12111a5e",
                "sha256:9add70b36c5666a2ed02b43b335fe19002ee5235efd4b8a89bfcf9005bebac0d",
                "sha256:9bf40443012702a1d2070043cb6291650a0841ece432556f784f004937f0f32c",
                "sha256:ade5e387d2ad0d7ebf59146cc00c8044acbd863725f887353a10df825fc8ae21",
                "sha256:b00c1de48212e4cc9603895652c5c410df699856a2853135b3967591e4beebc2",
                "sha256:b1282f8c00509d99fef04d8ba936b156d419be841854fe901d8ae224c59f0be5",
                "sha256:b2051432115498d3562c084a49bba65d97cf251f5a331c64a12ee7e04dacc51b",
                "sha256:ba59edeaa2fc6114428f1637ffff42da1e311e29382d81b339c1817d37ec93c6",
                "sha256:c8716a48d94b06bb3b2524c2b77e055fb313aeb4ea620c8dd03a105574ba704f",
                "sha256:cd5df75523866410809ca100dc9681e301e3c27567cf498077e8551b6d20e42f",
                "sha256:cdb132fc825c38e1aeec2c8aa9338310d29d337bebbd7baa06889d09a60a1fa2",
                "sha256:e249096428b3ae81b08327a63a485ad0878de3fb939049038579ac0ef61e17e7",
                "sha256:e8313f01ba26fbbe36c7be1966a7b7424942f670f38e666995b88d012765b9be"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==1.1.1"
        },
        "multidict": {
            "hashes": [
                "sha256:317f96bc0950d249e96d8d29ab556d01dd38888fbe68324f46fd834b430169f1",
                "sha256:42f56542166040b4474c0c608ed051732033cd821126493cf25b6c276df7dd35",
                "sha256:4b7df040fb5fe826d689204f9b544af469593fb3ff3a069a6ad3409f742f5928",
                "sha256:544fae9261232a97102e27a926019100a9db75bec7b37feedd74b3aa82f29969",
                "sha256:620b37c3fea181dab09267cd5a84b0f23fa043beb8bc50d8474dd9694de1fa6e",
                "sha256:6e6fef114741c4d7ca46da8449038ec8b1e880bbe68674c01ceeb1ac8a648e78",
                "sha256:7774e9f6c9af3f12f296131453f7b81dabb7ebdb948483362f5afcaac8a826f1",
                "sha256:85cb26c38c96f76b7ff38b86c9d560dea10cf3459bb5f4caf72fc1bb932c7136",
                "sha256:a326f4240123a2ac66bb163eeba99578e9d63a8654a59f4688a79198f9aa10f8",
                "sha256:ae402f43604e3b2bc41e8ea8b8526c7fa7139ed76b0d64fc48e28125925275b2",
                "sha256:aee283c49601fa4c13adc64c09c978838a7e812f85377ae130a24d7198c0331e",
                "sha256:b51249fdd2923739cd3efc95a3d6c363b67bbf779208e9f37fd5e68540d1a4d4",
                "sha256:bb519becc46275c594410c6c28a8a0adc66fe24fef154a9addea54c1adb006f5",
                "sha256:c2c37185fb0af79d5c117b8d2764f4321eeb12ba8c141a95d0aa8c2c1d0a11dd",
                "sha256:dc561313279f9d05a3d0ffa89cd15ae477528ea37aa9795c4654588a3287a9ab",
                "sha256:e439c9a10a95cb32abd708bb8be83b2134fa93790a4fb0535ca36db3dda94d20",
                "sha256:fc3b4adc2ee8474cb3cd2a155305d5f8eda0a9c91320f83e55748e1fcb68f8e3"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==4.7.5"
        },
        "requests": {
            "hashes": [
                "sha256:43999036bfa82904b6af1d99e4882b560e5e2c68e5c4b0aa03b655f3d7d73fee",
                "sha256:b3f43d496c6daba4493e7c431722aeb7dbc6288f52a6e04e7b6023b0247817e6"
            ],
            "index": "pypi",
            "version": "==2.23.0"
        },
        "slackclient": {
            "hashes": [
                "sha256:16ebbfa1c34374fa8c508d0c8e5c670e41bba4a3f62c469ab1ee1b8225a939fa",
                "sha256:d37e4f91be9cf9d5c1a1698f44a37671fc92823ff01146cd827415f35fabe636"
            ],
            "index": "pypi",
            "version": "==2.5.0"
        },
        "tornado": {
            "hashes": [
                "sha256:0fe2d45ba43b00a41cd73f8be321a44936dc1aba233dee979f17a042b83eb6dc",
                "sha256:22aed82c2ea340c3771e3babc5ef220272f6fd06b5108a53b4976d0d722bcd52",
                "sha256:2c027eb2a393d964b22b5c154d1a23a5f8727db6fda837118a776b29e2b8ebc6",
                "sha256:5217e601700f24e966ddab689f90b7ea4bd91ff3357c3600fa1045e26d68e55d",
                "sha256:5618f72e947533832cbc3dec54e1dffc1747a5cb17d1fd91577ed14fa0dc081b",
                "sha256:5f6a07e62e799be5d2330e68d808c8ac41d4a259b9cea61da4101b83cb5dc673",
                "sha256:c58d56003daf1b616336781b26d184023ea4af13ae143d9dda65e31e534940b9",
                "sha256:c952975c8ba74f546ae6de2e226ab3cc3cc11ae47baf607459a6728585bb542a",
                "sha256:c98232a3ac391f5faea6821b53db8db461157baa788f5d6222a193e9456e1740"
            ],
            "index": "pypi",
            "version": "==6.0.4"
        },
        "urllib3": {
            "hashes": [
                "sha256:3018294ebefce6572a474f0604c2021e33b3fd8006ecd11d62107a5d2a963527",
                "sha256:88206b0eb87e6d677d424843ac5209e3fb9d0190d0ee169599165ec25e9d9115"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3' and python_version < '4'",
            "version": "==1.25.9"
        },
        "yarl": {
            "hashes": [
                "sha256:0c2ab325d33f1b824734b3ef51d4d54a54e0e7a23d13b86974507602334c2cce",
                "sha256:0ca2f395591bbd85ddd50a82eb1fde9c1066fafe888c5c7cc1d810cf03fd3cc6",
                "sha256:2098a4b4b9d75ee352807a95cdf5f10180db903bc5b7270715c6bbe2551f64ce",
                "sha256:25e66e5e2007c7a39541ca13b559cd8ebc2ad8fe00ea94a2aad28a9b1e44e5ae",
                "sha256:26d7c90cb04dee1665282a5d1a998defc1a9e012fdca0f33396f81508f49696d",
                "sha256:308b98b0c8cd1dfef1a0311dc5e38ae8f9b58349226aa0533f15a16717ad702f",
                "sha256:3ce3d4f7c6b69c4e4f0704b32eca8123b9c58ae91af740481aa57d7857b5e41b",
                "sha256:58cd9c469eced558cd81aa3f484b2924e8897049e06889e8ff2510435b7ef74b",
                "sha256:5b10eb0e7f044cf0b035112446b26a3a2946bca9d7d7edb5e54a2ad2f6652abb",
                "sha256:6faa19d3824c21bcbfdfce5171e193c8b4ddafdf0ac3f129ccf0cdfcb083e462",
                "sha256:944494be42fa630134bf907714d40207e646fd5a94423c90d5b514f7b0713fea",
                "sha256:a161de7e50224e8e3de6e184707476b5a989037dcb24292b391a3d66ff158e70",
                "sha256:a4844ebb2be14768f7994f2017f70aca39d658a96c786211be5ddbe1c68794c1",
                "sha256:c2b509ac3d4b988ae8769901c66345425e361d518aecbe4acbfc2567e416626a",
                "sha256:c9959d49a77b0e07559e579f38b2f3711c2b8716b8410b320bf9713013215a1b",
                "sha256:d8cdee92bc930d8b09d8bd2043cedd544d9c8bd7436a77678dd602467a993080",
                "sha256:e15199cdb423316e15f108f51249e44eb156ae5dba232cb73be555324a1d49c2"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==1.4.2"
        }
    },
    "develop": {
        "astroid": {
            "hashes": [
                "sha256:71ea07f44df9568a75d0f354c49143a4575d90645e9fead6dfb52c26a85ed13a",
                "sha256:840947ebfa8b58f318d42301cf8c0a20fd794a33b61cc4638e28e9e61ba32f42"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==2.3.3"
        },
        "isort": {
            "hashes": [
                "sha256:54da7e92468955c4fceacd0c86bd0ec997b0e1ee80d97f67c35a78b719dccab1",
                "sha256:6e811fcb295968434526407adb8796944f1988c5b65e8139058f2014cbe100fd"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==4.3.21"
        },
        "lazy-object-proxy": {
            "hashes": [
                "sha256:0c4b206227a8097f05c4dbdd323c50edf81f15db3b8dc064d08c62d37e1a504d",
                "sha256:194d092e6f246b906e8f70884e620e459fc54db3259e60cf69a4d66c3fda3449",
                "sha256:1be7e4c9f96948003609aa6c974ae59830a6baecc5376c25c92d7d697e684c08",
                "sha256:4677f594e474c91da97f489fea5b7daa17b5517190899cf213697e48d3902f5a",
                "sha256:48dab84ebd4831077b150572aec802f303117c8cc5c871e182447281ebf3ac50",
                "sha256:5541cada25cd173702dbd99f8e22434105456314462326f06dba3e180f203dfd",
                "sha256:59f79fef100b09564bc2df42ea2d8d21a64fdcda64979c0fa3db7bdaabaf6239",
                "sha256:8d859b89baf8ef7f8bc6b00aa20316483d67f0b1cbf422f5b4dc56701c8f2ffb",
                "sha256:9254f4358b9b541e3441b007a0ea0764b9d056afdeafc1a5569eee1cc6c1b9ea",
                "sha256:9651375199045a358eb6741df3e02a651e0330be090b3bc79f6d0de31a80ec3e",
                "sha256:97bb5884f6f1cdce0099f86b907aa41c970c3c672ac8b9c8352789e103cf3156",
                "sha256:9b15f3f4c0f35727d3a0fba4b770b3c4ebbb1fa907dbcc046a1d2799f3edd142",
                "sha256:a2238e9d1bb71a56cd710611a1614d1194dc10a175c1e08d75e1a7bcc250d442",
                "sha256:a6ae12d08c0bf9909ce12385803a543bfe99b95fe01e752536a60af2b7797c62",
                "sha256:ca0a928a3ddbc5725be2dd1cf895ec0a254798915fb3a36af0964a0a4149e3db",
                "sha256:cb2c7c57005a6804ab66f106ceb8482da55f5314b7fcb06551db1edae4ad1531",
                "sha256:d74bb8693bf9cf75ac3b47a54d716bbb1a92648d5f781fc799347cfc95952383",
                "sha256:d945239a5639b3ff35b70a88c5f2f491913eb94871780ebfabb2568bd58afc5a",
                "sha256:eba7011090323c1dadf18b3b689845fd96a61ba0a1dfbd7f24b921398affc357",
                "sha256:efa1909120ce98bbb3777e8b6f92237f5d5c8ea6758efea36a473e1d38f7d3e4",
                "sha256:f3900e8a5de27447acbf900b4750b0ddfd7ec1ea7fbaf11dfa911141bc522af0"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==1.4.3"
        },
        "mccabe": {
            "hashes": [
                "sha256:ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42",
                "sha256:dd8d182285a0fe56bace7f45b5e7d1a6ebcbf524e8f3bd87eb0f125271b8831f"
            ],
            "version": "==0.6.1"
        },
        "pylint": {
            "hashes": [
                "sha256:3db5468ad013380e987410a8d6956226963aed94ecb5f9d3a28acca6d9ac36cd",
                "sha256:886e6afc935ea2590b462664b161ca9a5e40168ea99e5300935f6591ad467df4"
            ],
            "index": "pypi",
            "version": "==2.4.4"
        },
        "six": {
            "hashes": [
                "sha256:236bdbdce46e6e6a3d61a337c0f8b763ca1e8717c03b369e87a7ec7ce1319c0a",
                "sha256:8f3cd2e254d8f793e7f3d6d9df77b92252b52637291d0f0da013c76ea2724b6c"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
            "version": "==1.14.0"
        },
        "wrapt": {
            "hashes": [
                "sha256:565a021fd19419476b9362b05eeaa094178de64f8361e44468f9e9d7843901e1"
            ],
            "version": "==1.11.2"
        }
    }
}

```
</details>
Can't reproduce the issue, and under no condition will `project.environment.reversed_dependencies()` return `None`:

https://github.com/pypa/pipenv/blob/6a53d5c593c133c6295a2c062d785b0dc745843d/pipenv/environment.py#L666-L693

Resolving patch:
diff --git a/pipenv/core.py b/pipenv/core.py
--- a/pipenv/core.py
+++ b/pipenv/core.py
@@ -1812,7 +1812,10 @@ def do_outdated(pypi_mirror=None, pre=False, clear=False):
         (pkg.project_name, pkg.parsed_version, pkg.latest_version)
         for pkg in project.environment.get_outdated_packages()
     }
-    reverse_deps = project.environment.reverse_dependencies()
+    reverse_deps = {
+        canonicalize_name(name): deps
+        for name, deps in project.environment.reverse_dependencies().items()
+    }
     for result in installed_packages:
         dep = Requirement.from_line(str(result.as_requirement()))
         packages.update(dep.as_pipfile())
@@ -1842,9 +1845,9 @@ def do_outdated(pypi_mirror=None, pre=False, clear=False):
         version = None
         if name_in_pipfile:
             version = get_version(project.packages[name_in_pipfile])
-            reverse_deps = reverse_deps.get(name_in_pipfile)
-            if isinstance(reverse_deps, Mapping) and "required" in reverse_deps:
-                required = " {0} required".format(reverse_deps["required"])
+            rdeps = reverse_deps.get(canonicalize_name(package))
+            if isinstance(rdeps, Mapping) and "required" in rdeps:
+                required = " {0} required".format(rdeps["required"])
             if version:
                 pipfile_version_text = " ({0} set in Pipfile)".format(version)
             else:


Test patch: