Unable to lock packages with odd version numbers

Issue description

Running pipenv install pdfminer.six fails.

Expected result

It succeeds to install the package

Actual result

> pipenv install pdfminer.six --verbose
Installing pdfminer.six…
⠋Installing 'pdfminer.six'
$ ['/Users/tom/.virtualenvs/tempenv-6fe770333809/bin/pip', 'install', '--verbose', '--upgrade', 'pdfminer.six', '-i', 'https://pypi.org/simple']
Created temporary directory: /private/var/folders/9w/twrv54nd0v19gsbjhjs3mlhc0000gn/T/pip-ephem-wheel-cache-fojnad2a
Created temporary directory: /private/var/folders/9w/twrv54nd0v19gsbjhjs3mlhc0000gn/T/pip-req-tracker-avndeix4
Created requirements tracker '/private/var/folders/9w/twrv54nd0v19gsbjhjs3mlhc0000gn/T/pip-req-tracker-avndeix4'
Created temporary directory: /private/var/folders/9w/twrv54nd0v19gsbjhjs3mlhc0000gn/T/pip-install-putzczfh
1 location(s) to search for versions of pdfminer.six:
* https://pypi.org/simple/pdfminer-six/
Getting page https://pypi.org/simple/pdfminer-six/
Looking up "https://pypi.org/simple/pdfminer-six/" in the cache
Request header has "max_age" as 0, cache bypassed
Starting new HTTPS connection (1): pypi.org:443
https://pypi.org:443 "GET /simple/pdfminer-six/ HTTP/1.1" 304 0
Analyzing links from page https://pypi.org/simple/pdfminer-six/
  Found link https://files.pythonhosted.org/packages/ab/60/8df8a1f2c56e191fef9cb3dc70f951ef7ef5df85523382d45a94180d38de/pdfminer.six-20140915.zip#sha256=b734cbad2d9431a794e2c9cb6edfb1aad36f20461b65d20af8d89c3469453fe6 (from https://pypi.org/simple/pdfminer-six/), version: 20140915
......
Cleaning up...
Removed build tracker '/private/var/folders/9w/twrv54nd0v19gsbjhjs3mlhc0000gn/T/pip-req-tracker-avndeix4'

Adding pdfminer.six to Pipfile's [packages]…
Pipfile.lock not found, creating…
Locking [dev-packages] dependencies…
Locking [packages] dependencies…
using sources: [{'url': 'https://pypi.org/simple', 'verify_ssl': True, 'name': 'pypi'}]
Using pip: -i https://pypi.org/simple

                          ROUND 1
Current constraints:
  pdfminer-six

Finding the best candidates:
Using pip: -i https://pypi.org/simple

                          ROUND 1
Current constraints:
  pdfminer-six

Finding the best candidates:

Warning: Your dependencies could not be resolved. You likely have a mismatch in your sub-dependencies.
  First try clearing your dependency cache with $ pipenv lock --clear, then try the original command again.
 Alternatively, you can use $ pipenv install --skip-lock to bypass this mechanism, then run $ pipenv graph to inspect the situation.
  Hint: try $ pipenv lock --pre if it is a pre-release dependency.
Could not find a version that matches pdfminer-six
No versions found
Was https://pypi.org/simple reachable?
Warning: Your dependencies could not be resolved. You likely have a mismatch in your sub-dependencies.
  First try clearing your dependency cache with $ pipenv lock --clear, then try the original command again.
 Alternatively, you can use $ pipenv install --skip-lock to bypass this mechanism, then run $ pipenv graph to inspect the situation.
  Hint: try $ pipenv lock --pre if it is a pre-release dependency.
Could not find a version that matches pdfminer-six
No versions found
Was https://pypi.org/simple reachable?

Steps to replicate

pipenv install pdfminer.six

Support

$ pipenv --support

Pipenv version: '2018.10.10.dev0'

Pipenv location: '/Users/tom/projects/pipenv/pipenv'

Python location: '/Users/tom/.virtualenvs/tempenv-6fe770333809/bin/python3'

Python installations found:

• 3.7.0: /Users/tom/.pyenv/shims/python3.7m
• 3.7.0: /Users/tom/.pyenv/shims/python3.7
• 3.7.0: /usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/bin/python3.7
• 3.7.0: /usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/bin/python3.7m
• 3.6.5: /Users/tom/.virtualenvs/tempenv-6fe770333809/bin/python3
• 3.6.5: /Users/tom/.pyenv/shims/python3
• 3.6.5: /Users/tom/.pyenv/shims/python
• 3.6.5: /Users/tom/.pyenv/shims/python3.6
• 2.7.15: /usr/local/Cellar/python@2/2.7.15_1/Frameworks/Python.framework/Versions/2.7/bin/python2.7
• 2.7.10: /usr/bin/python
• 2.7.10: /usr/bin/pythonw
• 2.7.10: /System/Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7

PEP 508 Information:

{'implementation_name': 'cpython',
 'implementation_version': '3.6.5',
 'os_name': 'posix',
 'platform_machine': 'x86_64',
 'platform_python_implementation': 'CPython',
 'platform_release': '18.0.0',
 'platform_system': 'Darwin',
 'platform_version': 'Darwin Kernel Version 18.0.0: Wed Aug 22 20:13:40 PDT '
                     '2018; root:xnu-4903.201.2~1/RELEASE_X86_64',
 'python_full_version': '3.6.5',
 'python_version': '3.6',
 'sys_platform': 'darwin'}

System environment variables:

• AWS_ACCESS_KEY_ID
• AWS_SECRET_ACCESS_KEY
• AWS_SESSION_TOKEN
• Apple_PubSub_Socket_Render
• COLORFGBG
• COLORTERM
• EDITOR
• HEX_REPO_KEY
• HOME
• HOMEBREW_AUTO_UPDATE_SECS
• ITERM_PROFILE
• ITERM_SESSION_ID
• LANG
• LC_ALL
• LC_CTYPE
• LOGNAME
• OL_client_id
• OL_client_secret
• OL_region
• OL_username
• ONFIDO_PROFILE
• ONFIDO_ROLE
• OP_SESSION
• OP_entry_name
• PATH
• PWD
• PYENV_SHELL
• SECURITYSESSIONID
• SHELL
• SHLVL
• SSH_AUTH_SOCK
• TERM
• TERM_PROGRAM
• TERM_PROGRAM_VERSION
• TERM_SESSION_ID
• TMPDIR
• USER
• VIRTUAL_ENV
• VIRTUAL_ENV_DISABLE_PROMPT
• XPC_FLAGS
• XPC_SERVICE_NAME
• __CF_USER_TEXT_ENCODING
• nvm_prefix
• PYTHONDONTWRITEBYTECODE
• PIP_SHIMS_BASE_MODULE
• PIP_PYTHON_PATH

Pipenv–specific environment variables:

Debug–specific environment variables:

• PATH: /usr/local/sbin:/Users/tom/.local/bin/:/Users/tom/.virtualenvs/tempenv-6fe770333809/bin:/Users/tom/.pyenv/shims:/Users/tom/.cargo/bin:/Users/tom/bin/:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/MacGPG2/bin:/Library/Frameworks/Mono.framework/Versions/Current/Commands:/Applications/Wireshark.app/Contents/MacOS
• SHELL: /usr/local/bin/fish
• EDITOR: charm
• LANG: en_US.UTF-8
• PWD: /private/var/folders/9w/twrv54nd0v19gsbjhjs3mlhc0000gn/T/tmp.ALE4xMXP
• VIRTUAL_ENV: /Users/tom/.virtualenvs/tempenv-6fe770333809

---

Contents of Pipfile (‘/private/var/folders/9w/twrv54nd0v19gsbjhjs3mlhc0000gn/T/tmp.ALE4xMXP/Pipfile’):

[[source]]
url = "https://pypi.org/simple"
verify_ssl = true
name = "pypi"

[packages]
pdfminer-six = "*"

[dev-packages]

[requires]
python_version = "3.6"

[orf]

I tested this with the latest master though. It worked if I added "pdfminer.six" with quotes to Pipfile. Without the quotes it would try and lock pdfminer.

[immerrr]

Looks like another duplicate of https://github.com/pypa/pipenv/issues/2956