filter-branch: stop depending on Perl
While git-filter-branch(1) is written as a shell script, the `--state-branch` feature depends on Perl to save and extract the object ID mappings. This can lead to subtle breakage though: - We execute `perl` directly without respecting the `PERL_PATH` configured by the distribution. As such, it may happen that we use the wrong version of Perl. - We install the script unchanged even if Perl isn't available at all on the system, so using `--state-branch` would lead to failure altogether in that case. Fix this by dropping Perl and instead implementing the feature with shell scripting exclusively. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt committed
Apr 16, 2025 at 14:16 UTC
f6d855091e73fdab8a39185a8392b9d0df7ed46f
1 file changed
+19
-18
git-filter-branch.sh
+19
-18
@@ -295,15 +295,18 @@ then
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if test -n "$state_commit"
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then
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echo "Populating map from $state_branch ($state_commit)" 1>&2
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- perl -e'open(MAP, "-|", "git show $ARGV[0]:filter.map") or die;
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- while (<MAP>) {
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- m/(.*):(.*)/ or die;
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- open F, ">../map/$1" or die;
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- print F "$2" or die;
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- close(F) or die;
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- }
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- close(MAP) or die;' "$state_commit" \
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- || die "Unable to load state from $state_branch:filter.map"
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+
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+ git show "$state_commit:filter.map" >"$tempdir"/filter-map ||
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+ die "Unable to load state from $state_branch:filter.map"
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+ while read line
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+ do
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+ case "$line" in
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+ *:*)
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+ echo "${line%:*}" >../map/"${line#*:}";;
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+ *)
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+ die "Unable to load state from $state_branch:filter.map";;
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+ esac
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+ done <"$tempdir"/filter-map
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else
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echo "Branch $state_branch does not exist. Will create" 1>&2
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fi
@@ -633,15 +636,13 @@ if test -n "$state_branch"
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then
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echo "Saving rewrite state to $state_branch" 1>&2
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state_blob=$(
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- perl -e'opendir D, "../map" or die;
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- open H, "|-", "git hash-object -w --stdin" or die;
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- foreach (sort readdir(D)) {
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- next if m/^\.\.?$/;
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- open F, "<../map/$_" or die;
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- chomp($f = <F>);
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- print H "$_:$f\n" or die;
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- }
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- close(H) or die;' || die "Unable to save state")
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+ for file in ../map/*
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+ do
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+ from_commit=$(basename "$file")
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+ to_commit=$(cat "$file")
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+ echo "$from_commit:$to_commit"
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+ done | git hash-object -w --stdin || die "Unable to save state"
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+ )
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state_tree=$(printf '100644 blob %s\tfilter.map\n' "$state_blob" | git mktree)
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if test -n "$state_commit"
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then