Re-vendoring rust-gst-plugin-gtk4
===========================
Current Ubuntu Main Inclusion policy requires that Rust apps in Ubuntu main
be vendored.

https://canonical-ubuntu-project.readthedocs-hosted.com/MIR/mir-rust/

Prerequisites
=============
sudo apt install cargo-vendor-filterer dh-cargo-tools dpkg-dev git quilt

Updating vendored crates
========================
Run
debian/rules vendor

This next part is currently more awkward to automate so we do it manually.
See https://launchpad.net/bugs/2115573

rm Cargo.toml
CARGO_VENDOR_DIR=debian/missing-sources/ /usr/share/cargo/bin/dh-cargo-vendored-sources
# Use the output of that command to replace the XS-Vendored-Sources-Rust line
# in debian/control then continue.
# If XS-Vendored-Sources-Rust is already up to date, the command won't output
# anything and you can skip to restoring Cargo.toml.
git add debian/control
git commit -m "Update XS-Vendored-Sources-Rust field"
git reset --hard # restore Cargo.toml

Debian Workflow
===============
Debian uses a complex workflow to manage this package
described at https://deb.li/rtbook

The debian/ files checked into Salsa are more minimal than expected for
a Debian package. The other files are generated.

Ubuntu Workflow
===============
This package is managed in Ubuntu with git-ubuntu at
https://code.launchpad.net/ubuntu/+source/rust-gst-plugin-gtk4

The documentation is still a work-in-progress and is scattered across
a few different places:
- https://canonical-git-ubuntu.readthedocs-hosted.com/
- https://github.com/canonical/ubuntu-maintainers-handbook/blob/main/PackageMerging.md
- https://canonical-ubuntu-packaging-guide.readthedocs-hosted.com

New Version
===========
If you need a new version of rust-gst-plugin-gtk4, it is generally easiest
to get this done in Debian first and then merge it into Ubuntu. If that isn't
practical, here are steps.

# Create a local temporary empty upstream branch with these instructions
https://honk.sigxcpu.org/projects/git-buildpackage/manual-html/gbp.import.convert.html#gbp.import.upstream.not.on.branch

# Then…
gbp import-orig --uscan --debian-branch=ubuntu/devel
dch -i # Create a new debian/changelog with the appropriate upstream version number

# Finally do a find and replace to update the version number in debian/control
# and debian/tests/control from the old upstream version number to the new
# upstream version number.
