From 0b3d85925751c2b3fd49effa50f7bd7b558b4926 Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Fri, 12 Jan 2018 11:02:19 +0000
Subject: scripts: add backporting script

This adds a simple script for backporting pull requests to older
branches. It accepts as parameters a list of pull request numbers which
whose commits are to be cherry-picked. The identification of PRs
currently happens by using the commit message of the merge of the PR,
which should conform to the message "Merge pull request #<PR>".

While the heuristic works in practice, we could instead also use the
direct references from GitHub via "pull/#<PR>/head". This requires the
user to have all these references fetched, though, so we can just use
the current heuristic until we experience any issues with that.
---
 script/backport.sh | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100755 script/backport.sh

(limited to 'script')

diff --git a/script/backport.sh b/script/backport.sh
new file mode 100755
index 000000000..3c2f899d6
--- /dev/null
+++ b/script/backport.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+if test $# -eq 0
+then
+    echo "USAGE: $0 <#PR> [<#PR>...]"
+    exit
+fi
+
+commits=
+
+for pr in $*
+do
+    mergecommit=$(git rev-parse ":/Merge pull request #$pr" || exit 1)
+    mergebase=$(git merge-base "$mergecommit"^1 "$mergecommit"^2 || exit 1)
+
+    commits="$commits $(git rev-list --reverse "$mergecommit"^2 ^"$mergebase")"
+done
+
+echo "Cherry-picking the following commits:"
+git rev-list --no-walk --oneline $commits
+echo
+
+git cherry-pick $commits
-- 
cgit v1.2.1