pip: Update readme with help output

Author: bbhtt

pip/readme.md

@@ -20,15 +20,15 @@ This requires `requirements-parser` which can be installed on your host with `pi
 
 You can also list multiple packages in single command:
 ```
-flatpak-pip-generator --runtime='org.freedesktop.Sdk//22.08' foo\>=1.0.0,\<2.0.0 bar 
+flatpak-pip-generator --runtime='org.freedesktop.Sdk//22.08' foo\>=1.0.0,\<2.0.0 bar
 ```
 
-If your project contains a [requirements.txt file](https://pip.readthedocs.io/en/stable/user_guide/#requirements-files) with all the project dependencies, you can use 
+If your project contains a [requirements.txt file](https://pip.readthedocs.io/en/stable/user_guide/#requirements-files) with all the project dependencies, you can use
 ```
 flatpak-pip-generator --runtime='org.freedesktop.Sdk//22.08' --requirements-file='/the/path/to/requirements.txt' --output pypi-dependencies
 ```
 
-You can use that in your manifest like 
+You can use that in your manifest like
 ```json
 "modules": [
   "pypi-dependencies.json",
@@ -40,19 +40,35 @@ You can use that in your manifest like
 
 ## Options
 
-* `--python2`: Build with Python 2. Note that you will have to build [the Python 2 shared-module](https://github.com/flathub/shared-modules/tree/master/python2.7) as it is not in any runtime.
-* `--build-isolation`: Enable build isolation with pip (recommended but not always work).
-* `--cleanup=(scripts|all)`: Add `cleanup` to the manifest. This is used when the packages installed are only used at build time.
-* `--build-only`: Alias to `--cleanup=all`.
-* `--requirements-file=`, `-r`: Reads the list of packages from `requirements.txt` file. Mutually exclusive with `--pyproject-file`.
-* `--pyproject-file=`: Reads the list of packages from `pyproject.toml` file. Mutually exclusive with `--requirements-file` or `r`.
-* `--ignore-pkg=`: Ignore a specific package name in a requirements-file, otherwise ignored.
-* `--checker-data`: This adds `x-checker-data` to modules so you will be notified when new releases happen. See [flatpak-external-data-checker](https://github.com/flathub/flatpak-external-data-checker) for more details.
-* `--runtime=`: Runs `pip` inside of a specific Flatpak runtime instead of on your host. Highly recommended for reproducability and portability. Examples would be `org.freedesktop.Sdk//22.08` or `org.gnome.Sdk/aarch64/43`.
-* `--ignore-errors=`: Allow the generation of empty or otherwise broken files when downloading packages fails.
-* `--ignore-installed=`: Comma-separated list of package names for which pip should ignore already installed packages. Useful when the package is installed in the SDK but not in the runtime.
-* `--output=`: Sets an output file.
-* `--yaml`: Outputs a YAML file.
+```
+usage: flatpak-pip-generator.py [-h] [--python2] [--cleanup {scripts,all}] [--requirements-file REQUIREMENTS_FILE] [--pyproject-file PYPROJECT_FILE] [--build-only] [--build-isolation]
+                                [--ignore-installed IGNORE_INSTALLED] [--checker-data] [--output OUTPUT] [--runtime RUNTIME] [--yaml] [--ignore-errors] [--ignore-pkg [IGNORE_PKG ...]]
+                                [packages ...]
+
+positional arguments:
+  packages
+
+options:
+  -h, --help            show this help message and exit
+  --python2             Look for a Python 2 package
+  --cleanup {scripts,all}
+                        Select what to clean up after build
+  --requirements-file, -r REQUIREMENTS_FILE
+                        Specify requirements.txt file. Cannot be used with pyproject file.
+  --pyproject-file PYPROJECT_FILE
+                        Specify pyproject.toml file. Cannot be used with requirements file.
+  --build-only          Clean up all files after build
+  --build-isolation     Do not disable build isolation. Mostly useful on pip that does't support the feature.
+  --ignore-installed IGNORE_INSTALLED
+                        Comma-separated list of package names for which pip should ignore already installed packages. Useful when the package is installed in the SDK but not in the runtime.
+  --checker-data        Include x-checker-data in output for the "Flatpak External Data Checker"
+  --output, -o OUTPUT   Specify output file name
+  --runtime RUNTIME     Specify a flatpak to run pip inside of a sandbox, ensures python version compatibility. Format: $RUNTIME_ID//$RUNTIME_BRANCH
+  --yaml                Use YAML as output format instead of JSON
+  --ignore-errors       Ignore errors when downloading packages
+  --ignore-pkg [IGNORE_PKG ...]
+                        Ignore packages when generating the manifest. Needs to be specified with version constraints if present (e.g. --ignore-pkg 'foo>=3.0.0' 'baz>=21.0').
+```
 
 ## Development