git-subtree: Bail out if we find output from Rust rewrite
This is going to be forward compatible, but not backward compatible: projects are expected to adopt the new tool, but not go back to this old one. CC: Colin Stagner <ask+git@howdoi.land> CC: Johannes Schindelin <Johannes.Schindelin@gmx.de> Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ian Jackson committed
Jul 6, 2026 at 12:58 UTC
cd6ad979ab5a81800c40e32e7e92bdc6f0ec0090
1 file changed
+18
contrib/subtree/git-subtree.sh
+18
@@ -278,6 +278,20 @@ main () {
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"cmd_$arg_command" "$@"
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}
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+# Usage: reject_if_v2_config REV
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+#
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+# Bails if we find .git-subtree/config. This file is used by the RIIR
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+# git-subtree, which can read data from this script, but which generates
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+# data that this script cannot cope with. So if we find that the user's
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+# project has already been processed with the new tool, we stop, to
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+# avoid generating broken output.
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+reject_if_v2_config () {
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+ local config=.git-subtree/config
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+ if git rev-parse --verify -q "$rev:$config"; then
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+ die "fatal: tree contains $config: has been processed with new standalone (Rust) git-subtree; use that tool instead of this one. See https://codeberg.org/diziet/git-subtree https://crates.io/crates/git-subtree"
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+ fi
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+}
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+
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# Usage: cache_setup
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cache_setup () {
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assert test $# = 0
@@ -846,6 +860,7 @@ process_split_commit () {
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# Or: cmd_add REPOSITORY REF
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cmd_add () {
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+ reject_if_v2_config HEAD
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ensure_clean
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if test $# -eq 1
@@ -934,6 +949,8 @@ cmd_split () {
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die "fatal: you must provide exactly one revision, and optionally a repository. Got: '$*'"
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fi
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+ reject_if_v2_config "$rev"
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+
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# Now validate prefix against the commit, not the working tree
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if ! git cat-file -e "$rev:$dir" 2>/dev/null
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then
@@ -1034,6 +1051,7 @@ cmd_merge () {
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then
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repository="$2"
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fi
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+ reject_if_v2_config HEAD
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ensure_clean
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if test -n "$arg_addmerge_squash"