Update alerts

Some packages need a hand edit of the PKGBUILD at a known point of the upstream version line, which a bump of pkgver misses: a new major of a JDK needs a newer boot JDK in makedepends, a release changes the license, or the old major needs a package of its own. alerts names such points. Each rule fires on the step from current to the new version, and either holds the update or lets it through with a note for the maintainer.

alerts:
  - when: major
    note: Create the package for the old major
  - from: '0.4.0'
    hold: true
    note: License changes to Apache-2.0
  - match: '^29\+'
    hold: true
    note: Raise makedepends java-environment to 28

Field	Required	Description
when	one of when, from, match	major: the first number of the new version is greater than that of current, as in 28+25 → 29+1
from	one of when, from, match	a version: the new version is at or above it, and current is below it
match	one of when, from, match	an ERE: the new version matches it, and current does not
note	yes	one line of text for the maintainer. A number, a boolean or a date goes in quotes, as in note: '2024'
hold	no	true holds the update. Default false

A rule fires once at each crossing, when the new version meets its condition and current does not. A from rule can stay in the file after its release, and a when: major rule fires again at the next major. The versions are compared in pkgver form, as current holds them, with vercmp for from and by the first number for when: major, so 9 → 10 is a new major. A package without current fires no rule. A downgrade or a version jump that the package does not allow is skipped first, see Downgrades and version jumps.

With hold: true, check-all.sh writes held: <version>, logs the first line below and pushes nothing, and the README shows ✋ 29+1 held. The maintainer makes the edit, publishes the version by hand and sets current to it, and the rule no longer fires. Without hold, the update goes on and the log gets the second line. Each rule that fires logs its own line, so a held update shows the notes of the other rules too.

! myjdk-ea: update 28+25 → 29+1 held: Raise makedepends java-environment to 28
! myjdk-ea-bin: update 28+25 → 29+1 notice: Create the package for the old major

A held update gets the issue ✋ <package>: update held with the notes of every rule that fired, since a rule without hold no longer fires after the hand publish. The run closes it once the version is in the AUR. A published update with a note gets the issue 🔔 <package>: <version> notice, and the maintainer closes it after the edit, see Issues. A held update is no failure on the statistics card.

validate-pkg.sh refuses an entry that breaks the table: another key, not exactly one of when, from and match, or a value of the wrong kind. It also refuses when: major together with pkgver_format, because the fixed text of a format such as 4.%s holds the first number of every version. A rule that the check cannot evaluate fails the check of the package, so a broken rule never lets a held update through.