Compile fails with Vala 0.48

[bserem]

Expected Behavior

While trying to run ninja the compilation fails because of Vala.

Current Behavior

../src/Model/JsonObject.vala:34.5-34.33: error: Creation method of abstract class cannot be public.
    public JsonObject.from_object (Json.Object object) {
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
../src/Model/JsonObject.vala:339.5-339.26: error: Creation method of abstract class cannot be public.
    public JsonObjectArray (Json.Object object, string property_name) {
    ^^^^^^^^^^^^^^^^^^^^^^
../src/Services/RateLimiter.vala:91.5-91.22: error: Creation method of abstract class cannot be public.
    public QueuedEvent (string id) {
    ^^^^^^^^^^^^^^^^^^
Compilation failed: 3 error(s), 0 warning(s)

Possible Solution

Other projects had similiar experiences with Vala 0.42+ (akiraux/Akira@e21d4e1)

Steps to Reproduce (for bugs)

1. Try to install with latest version of Vala (debian testing in my case)

Your Environment (for bugs)

• Lights-Up Version: 480494a
• OS Info:

$ uname -a && cat /etc/os-release
Linux dwarf 5.5.0-13.1-liquorix-amd64 #1 ZEN SMP PREEMPT liquorix 5.5-16.1~bullseye (2020-03-25) x86_64 GNU/Linux
PRETTY_NAME="Debian GNU/Linux bullseye/sid"
NAME="Debian GNU/Linux"
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"