firefox-extensions: fix the damn uBlock update script

pkgs/by-name/firefox-extensions/addon-version-lister

@@ -0,0 +1,53 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p bash -p common-updater-scripts -p coreutils -p curl
+
+NEWLINE=$'\n'
+
+numeric_version() {
+  # TODO: consider `b<n>` or `rc<n>` suffixes?
+  echo "$1" | egrep --only-matching "[0-9.]+" | head -n1
+}
+
+sort_versions() {
+  local lines=
+  for v in $1; do
+    local n=$(numeric_version "$v")
+    lines="$lines$n $v$NEWLINE"
+  done
+  echo "$lines" | sort --version-sort --reverse | cut -d" " -f 2
+}
+
+set -ex
+url="$1"
+
+MAX_VERSIONS=${MAX_VERSIONS:-10}
+
+# check that caller supplied all arguments
+test -n "$url"
+test -n "$UPDATE_NIX_OLD_VERSION"
+
+# we need the bare git URL.
+# strip `https://github.com/OWNER/NAME/releases/download/...` -> `https://github.com/OWNER/NAME`
+repo_url="${url/\/releases*/}"
+
+set +x
+all_versions=$(list-git-tags --url="$repo_url")
+all_versions=$(sort_versions "$all_versions")
+
+# filter to the versions for which we can actually download an artifact.
+# some packages (uBlock) publish releases even before all artifacts are available.
+versions=()
+for v in $all_versions; do
+  test_url=''${url//$UPDATE_NIX_OLD_VERSION/$v}
+  if $(set -x; curl --fail "$test_url"); then
+    versions+=("$v")
+  fi
+
+  if [[ ${#versions[@]} -ge $MAX_VERSIONS ]]; then
+    # if we have a bunch of versions already, then exit now instead of crawling through hundreds more tags we're just going to throw away.
+    break
+  fi
+done
+
+set -x
+echo "${versions[*]}"

pkgs/by-name/firefox-extensions/package.nix

@@ -2,18 +2,27 @@
   callPackage,
   concatTextFile,
   fetchurl,
+  genericUpdater,
   jq,
   lib,
   newScope,
   nix-update-script,
   runCommand,
+  static-nix-shell,
   stdenv,
   strip-nondeterminism,
   unzip,
   writers,
+  writeShellScript,
   zip,
 }:
 let
+  addon-version-lister = static-nix-shell.mkBash {
+    pname = "addon-version-lister";
+    pkgs = [ "common-updater-scripts" "coreutils" "curl" ];
+    srcRoot = ./.;
+  };
+
   wrapAddon = addon: args:
   let
     extid = addon.passthru.extid;
@@ -107,14 +116,17 @@ let
       cp $src $out
     '';
 
-    passthru.updateScript = nix-update-script {
-      # ignore beta versions
-      extraArgs = [ "--version-regex" "([0-9.]+)$" ];
+    passthru.updateScript = genericUpdater {
+      versionLister = writeShellScript "${pname}-version-lister" ''
+        ${lib.getExe addon-version-lister} ${url}
+      '';
     };
     passthru.extid = extid;
   };
 
   firefox-extensions = (lib.makeScope newScope (self: with self; {
+    inherit addon-version-lister;
+
     unwrapped = lib.recurseIntoAttrs {
       # get names from:
       # - ~/ref/nix-community/nur-combined/repos/rycee/pkgs/firefox-addons/generated-firefox-addons.nix