Repository: pypa/pipenv

Issue:
The `--categories` argument of the `install` and `requirements` commands expects different values and formatting
### Issue description

The `requirements` and `install` commands have different expectations for the `--categories` argument.

### Expected result

With the following `Pipfile`:

```toml
[[source]]
url = "https://pypi.org/simple"
verify_ssl = true
name = "pypi"

[packages]
pyvisa = "*"

[internal]
requests = "*"

[dev-packages]

[requires]
python_version = "3.9"
```

```shell
> pipenv install --categories "packages internal"
> pipenv requirements --categories "packages internal"
```

I expect to see `pyvisa`, `requests`, and their dependencies printed to the console.

### Actual result

The `requirements` command prints only the PyPI index.

```shell
> pipenv install --categories "packages internal" --verbose
Installing dependencies from Pipfile.lock (476f79)...
Installing dependencies from Pipfile.lock (476f79)...
To activate this project's virtualenv, run pipenv shell.
Alternatively, run a command inside the virtualenv with pipenv run.
> pipenv requirements --categories "packages internal"
-i https://pypi.org/simple
> 
```

### Further Debugging

I found the `install` command recommends `packages` if `default` is used.

```shell
>  pipenv install --categories "default internal" --verbose
Usage: pipenv install [OPTIONS] [PACKAGES]...

ERROR:: Cannot install to category `default`-- did you mean `packages`?
```

Nothing is installed if a comma is used.

```shell
> pipenv install --categories "default,internal" --verbose    
Installing dependencies from Pipfile.lock (476f79)...
To activate this project's virtualenv, run pipenv shell.
Alternatively, run a command inside the virtualenv with pipenv run.
```

The `requirements` command expects `default` instead of `packages`.

```shell
> pipenv requirements --categories "packages"                   
-i https://pypi.org/simple
> pipenv requirements --categories "default" 
-i https://pypi.org/simple
pyvisa==1.13.0
typing-extensions==4.4.0 ; python_version >= '3.7'
```

It also expects multiple categories to be comma separated.

```shell
> pipenv requirements --categories "default internal"
-i https://pypi.org/simple
> pipenv requirements --categories "default,internal"
-i https://pypi.org/simple
pyvisa==1.13.0
typing-extensions==4.4.0 ; python_version >= '3.7'
certifi==2022.12.7 ; python_version >= '3.6'
charset-normalizer==3.0.1
idna==3.4 ; python_version >= '3.5'
requests==2.28.2
urllib3==1.26.14 ; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4, 3.5'
```

-------------------------------------------------------------------------------

<details><summary>$ pipenv --support</summary>

Pipenv version: `'2022.12.19'`

Pipenv location: `'/Users/sean/.local/pipx/venvs/pipenv/lib/python3.10/site-packages/pipenv'`

Python location: `'/Users/sean/.local/pipx/venvs/pipenv/bin/python'`

OS Name: `'posix'`

User pip version: `'22.3.1'`

user Python installations found:

  - `3.10.6`: `/opt/brew/bin/python3`
  - `3.9.13`: `/Users/sean/.pyenv/versions/3.9.13/bin/python3`
  - `3.9.6`: `/usr/bin/python3`
  - `3.9.5`: `/Users/sean/.pyenv/versions/3.9.5/bin/python3`

PEP 508 Information:

```
{'implementation_name': 'cpython',
 'implementation_version': '3.10.6',
 'os_name': 'posix',
 'platform_machine': 'x86_64',
 'platform_python_implementation': 'CPython',
 'platform_release': '22.2.0',
 'platform_system': 'Darwin',
 'platform_version': 'Darwin Kernel Version 22.2.0: Fri Nov 11 02:08:47 PST '
                     '2022; root:xnu-8792.61.2~4/RELEASE_X86_64',
 'python_full_version': '3.10.6',
 'python_version': '3.10',
 'sys_platform': 'darwin'}
```

System environment variables:

  - `PATH`
  - `__CFBundleIdentifier`
  - `SHELL`
  - `TERM`
  - `USER`
  - `TMPDIR`
  - `COMMAND_MODE`
  - `TERMINAL_EMULATOR`
  - `LOGIN_SHELL`
  - `__INTELLIJ_COMMAND_HISTFILE__`
  - `SSH_AUTH_SOCK`
  - `XPC_FLAGS`
  - `TERM_SESSION_ID`
  - `__CF_USER_TEXT_ENCODING`
  - `LOGNAME`
  - `LC_CTYPE`
  - `XPC_SERVICE_NAME`
  - `HOME`
  - `SHLVL`
  - `PWD`
  - `OLDPWD`
  - `PYENV_ROOT`
  - `PYENV_SHELL`
  - `PIPENV_VENV_IN_PROJECT`
  - `ZSH`
  - `PAGER`
  - `LESS`
  - `LSCOLORS`
  - `HOMEBREW_PREFIX`
  - `PS1`
  - `_`
  - `PIP_DISABLE_PIP_VERSION_CHECK`
  - `PIP_PYTHON_PATH`
  - `PYTHONDONTWRITEBYTECODE`
  - `PYTHONFINDER_IGNORE_UNSUPPORTED`

Pipenv–specific environment variables:

 - `PIPENV_VENV_IN_PROJECT`: `1`

Debug–specific environment variables:

  - `PATH`: `/Users/sean/.pyenv/shims:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/opt/brew/bin:/Library/Apple/usr/bin:/Users/sean/.local/bin`
  - `SHELL`: `/bin/zsh`
  - `PWD`: `/Users/sean/Projects/sandbox`


---------------------------

Contents of `Pipfile` ('/Users/sean/Projects/sandbox/Pipfile'):

```toml
[[source]]
url = "https://pypi.org/simple"
verify_ssl = true
name = "pypi"

[packages]
pyvisa = "*"

[internal]
requests = "*"

[dev-packages]

[requires]
python_version = "3.9"

```


Contents of `Pipfile.lock` ('/Users/sean/Projects/sandbox/Pipfile.lock'):

```json
{
    "_meta": {
        "hash": {
            "sha256": "db365c3aafb745edd4ecfc246d9a9369a1d4f0ea231c5d0093468a9eb2476f79"
        },
        "pipfile-spec": 6,
        "requires": {
            "python_version": "3.9"
        },
        "sources": [
            {
                "name": "pypi",
                "url": "https://pypi.org/simple",
                "verify_ssl": true
            }
        ]
    },
    "default": {
        "pyvisa": {
            "hashes": [
                "sha256:805c55a514b1993dd1e0e2b18377f36fb3db6c2cd4953886144307d0c80795ce",
                "sha256:89fa008b58465c928655459508513c51e942ca7bf3e2a727da869366e0c8f9c6"
            ],
            "index": "pypi",
            "version": "==1.13.0"
        },
        "typing-extensions": {
            "hashes": [
                "sha256:1511434bb92bf8dd198c12b1cc812e800d4181cfcb867674e0f8279cc93087aa",
                "sha256:16fa4864408f655d35ec496218b85f79b3437c829e93320c7c9215ccfd92489e"
            ],
            "markers": "python_version >= '3.7'",
            "version": "==4.4.0"
        }
    },
    "develop": {},
    "internal": {
        "certifi": {
            "hashes": [
                "sha256:35824b4c3a97115964b408844d64aa14db1cc518f6562e8d7261699d1350a9e3",
                "sha256:4ad3232f5e926d6718ec31cfc1fcadfde020920e278684144551c91769c7bc18"
            ],
            "markers": "python_version >= '3.6'",
            "version": "==2022.12.7"
        },
        "charset-normalizer": {
            "hashes": [
                "sha256:00d3ffdaafe92a5dc603cb9bd5111aaa36dfa187c8285c543be562e61b755f6b",
                "sha256:024e606be3ed92216e2b6952ed859d86b4cfa52cd5bc5f050e7dc28f9b43ec42",
                "sha256:0298eafff88c99982a4cf66ba2efa1128e4ddaca0b05eec4c456bbc7db691d8d",
                "sha256:02a51034802cbf38db3f89c66fb5d2ec57e6fe7ef2f4a44d070a593c3688667b",
                "sha256:083c8d17153ecb403e5e1eb76a7ef4babfc2c48d58899c98fcaa04833e7a2f9a",
                "sha256:0a11e971ed097d24c534c037d298ad32c6ce81a45736d31e0ff0ad37ab437d59",
                "sha256:0bf2dae5291758b6f84cf923bfaa285632816007db0330002fa1de38bfcb7154",
                "sha256:0c0a590235ccd933d9892c627dec5bc7511ce6ad6c1011fdf5b11363022746c1",
                "sha256:0f438ae3532723fb6ead77e7c604be7c8374094ef4ee2c5e03a3a17f1fca256c",
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                "sha256:292d5e8ba896bbfd6334b096e34bffb56161c81408d6d036a7dfa6929cff8783",
                "sha256:2c03cc56021a4bd59be889c2b9257dae13bf55041a3372d3295416f86b295fb5",
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                "sha256:f5057856d21e7586765171eac8b9fc3f7d44ef39425f85dbcccb13b3ebea806c",
                "sha256:f6f45710b4459401609ebebdbcfb34515da4fc2aa886f95107f556ac69a9147e",
                "sha256:f97e83fa6c25693c7a35de154681fcc257c1c41b38beb0304b9c4d2d9e164479",
                "sha256:f9d0c5c045a3ca9bedfc35dca8526798eb91a07aa7a2c0fee134c6c6f321cbd7",
                "sha256:ff6f3db31555657f3163b15a6b7c6938d08df7adbfc9dd13d9d19edad678f1e8"
            ],
            "version": "==3.0.1"
        },
        "idna": {
            "hashes": [
                "sha256:814f528e8dead7d329833b91c5faa87d60bf71824cd12a7530b5526063d02cb4",
                "sha256:90b77e79eaa3eba6de819a0c442c0b4ceefc341a7a2ab77d7562bf49f425c5c2"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==3.4"
        },
        "requests": {
            "hashes": [
                "sha256:64299f4909223da747622c030b781c0d7811e359c37124b4bd368fb8c6518baa",
                "sha256:98b1b2782e3c6c4904938b84c0eb932721069dfdb9134313beff7c83c2df24bf"
            ],
            "index": "pypi",
            "version": "==2.28.2"
        },
        "urllib3": {
            "hashes": [
                "sha256:076907bf8fd355cde77728471316625a4d2f7e713c125f51953bb5b3eecf4f72",
                "sha256:75edcdc2f7d85b137124a6c3c9fc3933cdeaa12ecb9a6a959f22797a0feca7e1"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4, 3.5'",
            "version": "==1.26.14"
        }
    },
    "pyvisa": {
        "certifi": {
            "hashes": [
                "sha256:35824b4c3a97115964b408844d64aa14db1cc518f6562e8d7261699d1350a9e3",
                "sha256:4ad3232f5e926d6718ec31cfc1fcadfde020920e278684144551c91769c7bc18"
            ],
            "markers": "python_version >= '3.6'",
            "version": "==2022.12.7"
        },
        "charset-normalizer": {
            "hashes": [
                "sha256:00d3ffdaafe92a5dc603cb9bd5111aaa36dfa187c8285c543be562e61b755f6b",
                "sha256:024e606be3ed92216e2b6952ed859d86b4cfa52cd5bc5f050e7dc28f9b43ec42",
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            ],
            "version": "==3.0.1"
        },
        "idna": {
            "hashes": [
                "sha256:814f528e8dead7d329833b91c5faa87d60bf71824cd12a7530b5526063d02cb4",
                "sha256:90b77e79eaa3eba6de819a0c442c0b4ceefc341a7a2ab77d7562bf49f425c5c2"
            ],
            "markers": "python_version >= '3.5'",
            "version": "==3.4"
        },
        "requests": {
            "hashes": [
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                "sha256:98b1b2782e3c6c4904938b84c0eb932721069dfdb9134313beff7c83c2df24bf"
            ],
            "index": "pypi",
            "version": "==2.28.2"
        },
        "urllib3": {
            "hashes": [
                "sha256:076907bf8fd355cde77728471316625a4d2f7e713c125f51953bb5b3eecf4f72",
                "sha256:75edcdc2f7d85b137124a6c3c9fc3933cdeaa12ecb9a6a959f22797a0feca7e1"
            ],
            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4, 3.5'",
            "version": "==1.26.14"
        }
    }
}

```
</details>




Discussion:

Resolving patch:
diff --git a/pipenv/cli/command.py b/pipenv/cli/command.py
--- a/pipenv/cli/command.py
+++ b/pipenv/cli/command.py
@@ -1,4 +1,5 @@
 import os
+import re
 import sys
 
 from pipenv import environments
@@ -21,6 +22,7 @@
     uninstall_options,
     verbose_option,
 )
+from pipenv.utils.dependencies import get_lockfile_section_using_pipfile_category
 from pipenv.utils.environment import load_dot_env
 from pipenv.utils.processes import subprocess_run
 from pipenv.vendor.click import (
@@ -779,11 +781,11 @@ def requirements(
         echo(" ".join([prefix, package_index["url"]]))
 
     deps = {}
-    categories_list = categories.split(",") if categories else []
+    categories_list = re.split(r", *| ", categories) if categories else []
 
     if categories_list:
         for category in categories_list:
-            category = category.strip()
+            category = get_lockfile_section_using_pipfile_category(category.strip())
             deps.update(lockfile.get(category, {}))
     else:
         if dev or dev_only:
diff --git a/pipenv/cli/options.py b/pipenv/cli/options.py
--- a/pipenv/cli/options.py
+++ b/pipenv/cli/options.py
@@ -1,4 +1,5 @@
 import os
+import re
 
 from pipenv.project import Project
 from pipenv.utils.internet import is_valid_url
@@ -235,7 +236,7 @@ def categories_option(f):
     def callback(ctx, param, value):
         state = ctx.ensure_object(State)
         if value:
-            for opt in value.split(" "):
+            for opt in re.split(r", *| ", value):
                 state.installstate.categories.append(opt)
         return value
 


Test patch:
diff --git a/tests/integration/test_install_categories.py b/tests/integration/test_install_categories.py
--- a/tests/integration/test_install_categories.py
+++ b/tests/integration/test_install_categories.py
@@ -18,7 +18,8 @@ def test_basic_category_install(pipenv_instance_private_pypi):
 
 @pytest.mark.categories
 @pytest.mark.install
-def test_multiple_category_install(pipenv_instance_private_pypi):
+@pytest.mark.parametrize('categories', ["prereq other", "prereq, other"])
+def test_multiple_category_install(pipenv_instance_private_pypi, categories):
     with pipenv_instance_private_pypi() as p:
         c = p.pipenv('install six --categories="prereq other"')
         assert c.returncode == 0