pipenv lock doesn't work after latest update

[J-M0]

Issue description

When trying to lock the dependencies for my project, it fails with this error

pipenv.exceptions.DependencyConflict: ERROR: Cannot resolve conflicting version django<3.0,>=2.2.9 while django==3.1.3 is locked.

even though Django 3.1 is not used in the project

Expected result

pipenv lock to succeed

Actual result

$ pipenv lock --verbose

Locking [dev-packages] dependencies...
Building requirements...
Resolving dependencies...
⠋ Locking...
                          ROUND 1                           
✘ Locking Failed! 
Current constraints:
  django-debug-toolbar (from -r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))

Finding the best candidates:
  found candidate django-debug-toolbar==3.1.1 (constraint was <any>)

Finding secondary dependencies:
  django-debug-toolbar==3.1.1 requires django>=2.2, sqlparse>=0.2.0

New dependencies found in this round:
  adding ['django', '>=2.2', '[]']
  adding ['sqlparse', '>=0.2.0', '[]']
Removed dependencies in this round:
------------------------------------------------------------
Result of round 1: not stable

                          ROUND 2                           
Current constraints:
  django>=2.2 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  django-debug-toolbar (from -r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  sqlparse>=0.2.0 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))

Finding the best candidates:
  found candidate django==3.1.3 (constraint was >=2.2)
  found candidate django-debug-toolbar==3.1.1 (constraint was <any>)
  found candidate sqlparse==0.4.1 (constraint was >=0.2.0)

Finding secondary dependencies:
  django-debug-toolbar==3.1.1 requires django>=2.2, sqlparse>=0.2.0
  django==3.1.3             requires asgiref<4,>=3.2.10, pytz, sqlparse>=0.2.2
  sqlparse==0.4.1           requires -

New dependencies found in this round:
  adding ['asgiref', '<4,>=3.2.10', '[]']
  adding ['pytz', '', '[]']
  adding ['sqlparse', '>=0.2.0,>=0.2.2', '[]']
Removed dependencies in this round:
  removing ['sqlparse', '>=0.2.0', '[]']
------------------------------------------------------------
Result of round 2: not stable

                          ROUND 3                           
Current constraints:
  asgiref<4,>=3.2.10 (from django==3.1.3->django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  django>=2.2 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  django-debug-toolbar (from -r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  pytz (from django==3.1.3->django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  sqlparse>=0.2.0,>=0.2.2 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))

Finding the best candidates:
  found candidate asgiref==3.3.1 (constraint was >=3.2.10,<4)
  found candidate django==3.1.3 (constraint was >=2.2)
  found candidate django-debug-toolbar==3.1.1 (constraint was <any>)
  found candidate pytz==2020.4 (constraint was <any>)
  found candidate sqlparse==0.4.1 (constraint was >=0.2.0,>=0.2.2)

Finding secondary dependencies:
  asgiref==3.3.1            requires -
  django==3.1.3             requires asgiref<4,>=3.2.10, pytz, sqlparse>=0.2.2
  django-debug-toolbar==3.1.1 requires django>=2.2, sqlparse>=0.2.0
  sqlparse==0.4.1           requires -
  pytz==2020.4              requires -
------------------------------------------------------------
Result of round 3: stable, done

Generating hashes:
  asgiref
  django
  django-debug-toolbar
  sqlparse
  pytz
Tried constraint: <InstallRequirement object: django<3.0,>=2.2.9 editable=False>
Traceback (most recent call last):
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 763, in <module>
    main()
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 759, in main
    parsed.requirements_dir, parsed.packages, parse_only=parsed.parse_only)
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 741, in _main
    resolve_packages(pre, clear, verbose, system, write, requirements_dir, packages)
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 714, in resolve_packages
    results = clean_results(results, resolver, project)
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 596, in clean_results
    entry_dict = translate_markers(entry.get_cleaned_dict(keep_outdated=False))
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 239, in get_cleaned_dict
    self.validate_constraints()
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 536, in validate_constraints
    raise DependencyConflict(msg)
pipenv.exceptions.DependencyConflict: ERROR: Cannot resolve conflicting version django<3.0,>=2.2.9 while django==3.1.3 is locked.
ROUND 1                           
Current constraints:
  django-debug-toolbar (from -r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))

Finding the best candidates:
  found candidate django-debug-toolbar==3.1.1 (constraint was <any>)

Finding secondary dependencies:
  django-debug-toolbar==3.1.1 requires django>=2.2, sqlparse>=0.2.0

New dependencies found in this round:
  adding ['django', '>=2.2', '[]']
  adding ['sqlparse', '>=0.2.0', '[]']
Removed dependencies in this round:
------------------------------------------------------------
Result of round 1: not stable

                          ROUND 2                           
Current constraints:
  django>=2.2 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  django-debug-toolbar (from -r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  sqlparse>=0.2.0 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))

Finding the best candidates:
  found candidate django==3.1.3 (constraint was >=2.2)
  found candidate django-debug-toolbar==3.1.1 (constraint was <any>)
  found candidate sqlparse==0.4.1 (constraint was >=0.2.0)

Finding secondary dependencies:
  django-debug-toolbar==3.1.1 requires django>=2.2, sqlparse>=0.2.0
  django==3.1.3             requires asgiref<4,>=3.2.10, pytz, sqlparse>=0.2.2
  sqlparse==0.4.1           requires -

New dependencies found in this round:
  adding ['asgiref', '<4,>=3.2.10', '[]']
  adding ['pytz', '', '[]']
  adding ['sqlparse', '>=0.2.0,>=0.2.2', '[]']
Removed dependencies in this round:
  removing ['sqlparse', '>=0.2.0', '[]']
------------------------------------------------------------
Result of round 2: not stable

                          ROUND 3                           
Current constraints:
  asgiref<4,>=3.2.10 (from django==3.1.3->django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  django>=2.2 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  django-debug-toolbar (from -r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  pytz (from django==3.1.3->django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))
  sqlparse>=0.2.0,>=0.2.2 (from django-debug-toolbar==3.1.1->-r /tmp/pipenv_gy3sdfkrequirements/pipenv-4p6znxo8-constraints.txt (line 2))

Finding the best candidates:
  found candidate asgiref==3.3.1 (constraint was >=3.2.10,<4)
  found candidate django==3.1.3 (constraint was >=2.2)
  found candidate django-debug-toolbar==3.1.1 (constraint was <any>)
  found candidate pytz==2020.4 (constraint was <any>)
  found candidate sqlparse==0.4.1 (constraint was >=0.2.0,>=0.2.2)

Finding secondary dependencies:
  asgiref==3.3.1            requires -
  django==3.1.3             requires asgiref<4,>=3.2.10, pytz, sqlparse>=0.2.2
  django-debug-toolbar==3.1.1 requires django>=2.2, sqlparse>=0.2.0
  sqlparse==0.4.1           requires -
  pytz==2020.4              requires -
------------------------------------------------------------
Result of round 3: stable, done

Generating hashes:
  asgiref
  django
  django-debug-toolbar
  sqlparse
  pytz
Tried constraint: <InstallRequirement object: django<3.0,>=2.2.9 editable=False>
Traceback (most recent call last):
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 763, in <module>
    main()
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 759, in main
    parsed.requirements_dir, parsed.packages, parse_only=parsed.parse_only)
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 741, in _main
    resolve_packages(pre, clear, verbose, system, write, requirements_dir, packages)
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 714, in resolve_packages
    results = clean_results(results, resolver, project)
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 596, in clean_results
    entry_dict = translate_markers(entry.get_cleaned_dict(keep_outdated=False))
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 239, in get_cleaned_dict
    self.validate_constraints()
  File "/home/kususer/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 536, in validate_constraints
    raise DependencyConflict(msg)
pipenv.exceptions.DependencyConflict: ERROR: Cannot resolve conflicting version django<3.0,>=2.2.9 while django==3.1.3 is locked.

Steps to replicate

pipenv install 'Django>=2.2.9,<3.0'
pipenv install --dev django-debug-toolbar

---

$ pipenv --support

Pipenv version: '2020.11.4'

Pipenv location: '/home/kususer/.local/lib/python3.6/site-packages/pipenv'

Python location: '/usr/bin/python3'

Python installations found:

• 3.6.8: /usr/bin/python3
• 3.6.8: /usr/bin/python3.6
• 3.6.8: /usr/bin/python3.6m
• 3.6.8: /bin/python3
• 3.6.8: /bin/python3.6
• 3.6.8: /bin/python3.6m
• 2.7.5: /usr/bin/python2
• 2.7.5: /usr/bin/python2.7
• 2.7.5: /bin/python2
• 2.7.5: /bin/python2.7

PEP 508 Information:

{'implementation_name': 'cpython',
 'implementation_version': '3.6.8',
 'os_name': 'posix',
 'platform_machine': 'x86_64',
 'platform_python_implementation': 'CPython',
 'platform_release': '3.10.0-1160.2.2.el7.x86_64',
 'platform_system': 'Linux',
 'platform_version': '#1 SMP Sat Oct 17 05:06:47 UTC 2020',
 'python_full_version': '3.6.8',
 'python_version': '3.6',
 'sys_platform': 'linux'}

System environment variables:

• COLORTERM
• DBUS_SESSION_BUS_ADDRESS
• DESKTOP_SESSION
• DISPLAY
• GDMSESSION
• GDM_LANG
• GJS_DEBUG_OUTPUT
• GJS_DEBUG_TOPICS
• GNOME_DESKTOP_SESSION_ID
• GNOME_SHELL_SESSION_MODE
• GNOME_TERMINAL_SCREEN
• GNOME_TERMINAL_SERVICE
• HOME
• IMSETTINGS_INTEGRATE_DESKTOP
• IMSETTINGS_MODULE
• LANG
• LESS
• LOGNAME
• LS_COLORS
• PATH
• PWD
• QT_IM_MODULE
• RPM_PACKAGER
• SESSION_MANAGER
• SHELL
• SHLVL
• SSH_AGENT_PID
• SSH_AUTH_SOCK
• TERM
• USER
• USERNAME
• VTE_VERSION
• WINDOWPATH
• XAUTHORITY
• XDG_CURRENT_DESKTOP
• XDG_DATA_DIRS
• XDG_MENU_PREFIX
• XDG_RUNTIME_DIR
• XDG_SEAT
• XDG_SESSION_DESKTOP
• XDG_SESSION_ID
• XDG_SESSION_TYPE
• XDG_VTNR
• XMODIFIERS
• fish_user_paths
• 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: /home/kususer/bin/:/home/kususer/.local/bin/:/home/kususer/.poetry/bin/:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin
• SHELL: /usr/bin/fish
• LANG: en_US.UTF-8
• PWD: /home/kususer/Documents/pl

---

Contents of Pipfile ('/home/kususer/Documents/pl/Pipfile'):

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

[packages]
django = ">=2.2.9,<3.0"

[dev-packages]
django-debug-toolbar = "*"

[requires]
python_version = "3.6"

Contents of Pipfile.lock ('/home/kususer/Documents/pl/Pipfile.lock'):

{
    "_meta": {
        "hash": {
            "sha256": "380611a92b6137f3ca308e9814f3889804511816acbb9b9411e8b3f3d7d73620"
        },
        "pipfile-spec": 6,
        "requires": {
            "python_version": "3.6"
        },
        "sources": [
            {
                "name": "pypi",
                "url": "https://pypi.org/simple",
                "verify_ssl": true
            }
        ]
    },
    "default": {
        "django": {
            "hashes": [
                "sha256:558cb27930defd9a6042133258caf797b2d1dee233959f537e3dc475cb49bd7c",
                "sha256:cf5370a4d7765a9dd6d42a7b96b53c74f9446cd38209211304b210fe0404b861"
            ],
            "index": "pypi",
            "version": "==2.2.17"
        },
        "pytz": {
            "hashes": [
                "sha256:3e6b7dd2d1e0a59084bcee14a17af60c5c562cdc16d828e8eba2e683d3a7e268",
                "sha256:5c55e189b682d420be27c6995ba6edce0c0a77dd67bfbe2ae6607134d5851ffd"
            ],
            "version": "==2020.4"
        },
        "sqlparse": {
            "hashes": [
                "sha256:017cde379adbd6a1f15a61873f43e8274179378e95ef3fede90b5aa64d304ed0",
                "sha256:0f91fd2e829c44362cbcfab3e9ae12e22badaa8a29ad5ff599f9ec109f0454e8"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==0.4.1"
        }
    },
    "develop": {}
}

[frostming]

Planning to cut a release after the regression issues are fixed and if no more to be added.