feat: add ability to downgrade aur package using git

This reverts commit cb15393 and brings
back `--git`.

Author: pbrisbin

dist/completion/downgrade/fish

@@ -4,6 +4,7 @@ complete -c $cmd -l pacman -xa "(complete -C(commandline -ct))" -d 'pacman comma
 complete -c $cmd -l pacman-conf -r -d 'pacman configuration file'
 complete -c $cmd -l pacman-cache -r -d 'pacman cache directory'
 complete -c $cmd -l pacman-log -r -d 'pacman log file'
+complete -c $cmd -l git -d 'uses git for choosing version, viable only for aur packages'
 complete -c $cmd -l maxdepth -x -d 'maximum depth to search for cached packages'
 complete -c $cmd -l ala-url -x -d 'location of ALA server'
 complete -c $cmd -l ala-only -d 'only use ALA server'

dist/completion/downgrade/zsh

@@ -20,6 +20,7 @@ _downgrade () {
     '--pacman-conf[pacman configuration file]:pacman config file:_files' \
     '*--pacman-cache[pacman cache directory]:pacman cache directory:_path_files -/' \
     '--pacman-log[pacman log file]:pacman log file:_files' \
+    '--git[uses git for choosing version, viable only for aur packages]' \
     '--maxdepth[maximum depth to search for cached packages]:maximum search depth' \
     '--ala-url[location of ALA server]:ala url' \
     '--ala-only[only use ALA server]' \

doc/downgrade.8.ronn

@@ -72,6 +72,15 @@ on the ALA.
     Pacman log file, default value is extracted from pacman configuration file, or
     otherwise defaults to _/var/log/pacman.log_.
 
+  * `--git`:
+    If the pacman cache contains the source repository for the package (e.g. if
+    you use yay and are downgrading an AUR package), present any version-like
+    tags as available for downgrading (together with cached packages if
+    present). If selected, build and install the package from sources checked
+    out at that tag.
+
+    See [EXAMPLES].
+
   * `--maxdepth`=<INTEGER>:
     Maximum depth to search for cached packages, defaults to _1_.
 
@@ -168,6 +177,11 @@ Non-interactively downgrade `foo` to `1.0.0-1`
 
     # downgrade --latest --prefer-cache --ignore never 'foo=1.0.0-1'
 
+Present cached `downgrade` pkgbuilds together with tags with version greater
+than 9
+
+    # downgrade --git --pacman-cache ~/.cache/yay --maxdepth 2 'downgrade>9.0.0'
+
 ## AUTHORS
 
 * Patrick Brisbin \<pbrisbin@gmail.com>

src/downgrade

@@ -19,6 +19,7 @@ $(gettext "Options"):
                   $(gettext "pacman log file,")
                   $(gettext "default value taken from pacman configuration file,")
                   $(gettext "or otherwise defaults to") "/var/log/pacman.log"
+  --git           $(gettext "uses git for choosing version, viable only for aur packages")
   --maxdepth      <$(gettext "integer")>
                   $(gettext "maximum depth to search for cached packages, defaults to") 1
   --ala-url       <url>
@@ -167,8 +168,10 @@ matches_name_version_filter() {
     return 0
   fi
 
-  version_regex="[^-]+-[0-9.]+"
-  pkg_version=$(sed -r "s/.*$name-($version_regex)-(any|$DOWNGRADE_ARCH)\\.pkg\\.tar\\.(gz|xz|zst)/\1/g" <<<"$pkg")
+  # version: 2025.11.12.r15.g0eed3fe
+  version_regex="[a-zA-Z0-9.]+"
+  hash_or_minor="([0-9]+|[a-z0-9]{6,})"
+  pkg_version=$(sed -r "s/.*$name-($version_regex)(-$hash_or_minor)?-(any|$DOWNGRADE_ARCH)\\.(git)?pkg\\.tar\\.(gz|xz|zst)/\1\2/g" <<<"$pkg")
   cmp=$(vercmp "$pkg_version" "$search_version")
 
   case "$operator" in
@@ -196,6 +199,34 @@ matches_name_version_filter() {
   esac
 }
 
+search_git() {
+  local name=$1 pairs path
+
+  # Delay this defaulting so #read_pacman_conf behavior is tested
+  if ((!${#PACMAN_CACHE[@]})); then
+    mapfile -t PACMAN_CACHE < <(read_pacman_conf CacheDir)
+  fi
+
+  for cache in "${PACMAN_CACHE[@]}"; do
+    path="$cache/$name" # directory name
+    if ! [[ -d "$path/.git" ]]; then
+      {
+        gettext "\`$path\" not a git directory, skipping..."
+        echo
+      } >&2
+      continue
+    fi
+
+    # TODO: in future could be enhanced by counting every commit
+    # that DOES NOT change version as minor like 0.0.1-2 instead of any
+    # pair = abcd12 1.0
+    pairs=$(git -C "$path" log -p --oneline --format="GIT: %h" PKGBUILD | grep -e 'GIT:.*' -e '+pkgver' | grep -Pzo 'GIT: .*\n\+pkgver=.*\n' | sed 's/GIT: \|+pkgver=//' | tr -d '\0')
+
+    # shellcheck disable=SC2086
+    echo "$path/$name" $pairs | awk '{for(i=2;i<NF;i+=2) printf "%s-%s-%s-any.gitpkg.tar.gz\n", $1, $(i+1), $i}' | sort -V
+  done
+}
+
 search_ala() {
   local name=$1 uriname pkgfile_re index
 
@@ -217,7 +248,10 @@ search_ala() {
 search_cache() {
   local name=$1 pkgfile_re index
 
-  pkgfile_re="$name-[^-]+-[0-9.]+-(any|$DOWNGRADE_ARCH)\\.pkg\\.tar\\.(gz|xz|zst)"
+  # version: 2025.11.12.r15.g0eed3fe
+  version_regex="[a-zA-Z0-9.]+"
+  hash_or_minor="([0-9]+|[a-z0-9]{6,})"
+  pkgfile_re="$name-($version_regex)(-$hash_or_minor)?-(any|$DOWNGRADE_ARCH)\\.pkg\\.tar\\.(gz|xz|zst)"
 
   # Delay this defaulting so #read_pacman_conf behavior is tested
   if ((!${#PACMAN_CACHE[@]})); then
@@ -258,7 +292,7 @@ output_package() {
   fi
 
   # Remote or local file
-  if [[ $path =~ ^/ ]]; then
+  if [[ $path =~ ^/ && ! ($path =~ gitpkg) ]]; then
     location="$(dirname "$path")"
     timestamp=$(stat -c '%y' "$path" | cut -d' ' -f1)
   else
@@ -293,7 +327,7 @@ extract_version_parts() {
     s|^.\{'${#pkgname}'\}-\?||;
 
     # Strip package extension
-    s|\.pkg\(\.tar\)\?\(\.[a-z0-9A-Z]\+\)\?$||;
+    s|\.\(git\)\?pkg\(\.tar\)\?\(\.[a-z0-9A-Z]\+\)\?$||;
 
     # (epoch:)?version(-release)?(-arch)? -> epoch,version,release,arch
     s|\(\([^:]*\):\)\?\([^-]*\)\(-\([^-]*\)\)\?\(-\(.*\)\)\?|\2,\3,\5,\7|;
@@ -320,6 +354,11 @@ process_term() {
 
   candidates=($(printf '%s\n' "${candidates[@]}" | sort_packages))
 
+  # this is already sorted
+  if ((DOWNGRADE_FROM_GIT)); then
+    candidates=($(search_git "$name" | filter_packages "$name" "$operator" "$version") "${candidates[@]}")
+  fi
+
   if (("${#candidates[@]}" == 0)); then
     {
       gettext "No results found"
@@ -440,6 +479,9 @@ parse_options() {
           exit 1
         fi
         ;;
+      --git)
+        DOWNGRADE_FROM_GIT=1
+        ;;
       --maxdepth)
         if [[ -n "$2" ]]; then
           shift
@@ -523,6 +565,34 @@ parse_options() {
   fi
 }
 
+build_pkg() {
+  local item="$1" path commit_hash build_failed versionreg hashreg gitpkgreg
+  if [[ "$item" =~ .*gitpkg.tar.gz ]]; then
+    # version: 2025.11.12.r15.g0eed3fe
+    versionreg="([a-zA-Z0-9]+\.?)*"
+    hashreg='[a-z0-9]{6,}'
+    #hash_or_minor="-([0-9]+|[a-z0-9]{6,})" # leaving this as a note, only hash should appear tho
+    gitpkgreg="(.*)-$versionreg-($hashreg)-(any|$DOWNGRADE_ARCH).gitpkg.tar.gz"
+    path=$(dirname "$item")
+    commit_hash=$(sed -r "s/$gitpkgreg/\3/" <<<"$item")
+
+    pushd "$path" >/dev/null
+    su -P "$(stat -c"%U" PKGBUILD)" -c "git checkout $commit_hash &>/dev/null && makepkg -fs | tee makepkg.log"
+    build_failed=$?
+    # NOTE: when force-canceling, users might need to manually do checkout master
+    # otherwise they won't be able to update that pkg using yay or whatever I guess...
+    su "$(stat -c"%U" PKGBUILD)" -c "git switch - &>/dev/null"
+    if ((build_failed)); then
+      exit 1
+    fi
+
+    item="$(find "$path" -maxdepth 1 -type f -name "$(sed -nr '/.*Finished making: ([^ ]+) ([^ ]+) .*/{s//\1-\2/;p}' makepkg.log)*" -print -quit)"
+    rm makepkg.log
+    popd >/dev/null
+  fi
+  printf "%s\0" "$item" >>new_to_install.downgrade
+}
+
 cli() {
   local conf_args=()
 
@@ -536,6 +606,14 @@ cli() {
 
   # Proceed with rest of workflow
   main "${terms[@]}"
+  if ((DOWNGRADE_FROM_GIT)); then
+    for item in "${to_install[@]}"; do
+      build_pkg "$item"
+    done
+    mapfile -d '' to_install <new_to_install.downgrade
+    rm new_to_install.downgrade
+  fi
+
   pacman -U "${pacman_args[@]}" "${to_install[@]}"
   prompt_to_ignore "${to_ignore[@]}"
 }
@@ -545,6 +623,7 @@ PACMAN="pacman"
 PACMAN_CONF="/etc/pacman.conf"
 DOWNGRADE_ARCH="$(pacman-conf Architecture | head -n 1)"
 DOWNGRADE_ALA_URL="https://archive.archlinux.org"
+DOWNGRADE_FROM_GIT=0
 DOWNGRADE_FROM_ALA=1
 DOWNGRADE_FROM_CACHE=1
 DOWNGRADE_MAXDEPTH=1

test/search_git.t

@@ -0,0 +1,16 @@
+  $ source "$TESTDIR/helper.sh"
+  > cache=$(mktemp -d)
+  > git clone -q "https://aur.archlinux.org/downgrade.git" "$cache/downgrade"
+  > write_pacman_conf "[options]" "CacheDir = $cache"
+  > export DOWNGRADE_FROM_GIT=1
+
+List packages based on git tags
+
+  $ search_git 'downgrade' | head -n 2
+  /tmp/*/downgrade-5.1.3-0bdb507-any.gitpkg.tar.gz (glob)
+  /tmp/*/downgrade-5.1.4-dee7bd9-any.gitpkg.tar.gz (glob)
+
+Outputs appropriately for filter_packages
+
+  $ search_git 'downgrade' | filter_packages 'downgrade' '=~' '^7' | head -n 1
+  /tmp/*/downgrade-7.0.0-513f504-any.gitpkg.tar.gz (glob)