1 files changed, 56 insertions, 0 deletions
diff --git a/extract-ruby-svn b/extract-ruby-svn
new file mode 100755
index 0000000..63bedb9
--- /dev/null
+++ b/extract-ruby-svn
@@ -0,0 +1,56 @@
+#!/bin/sh
+set -e
+
+sha1_to_rev() { git show -s --format=format:%B $1 | tail -n1 | grep -Po '(?<=@)[0-9]+'; }
+rev_to_sha1() { git log --format=format:%H -n1 --grep '^git-svn-id: .*@'$2' ' $1; }
+
+BRANCH_EXTRACT=trunk-origin
+[ "$(git branch --list $BRANCH_EXTRACT)" ] ||
+	git branch $BRANCH_EXTRACT ruby-src/trunk
+
+[ ! -f trunk-work/.git ] &&
+	git worktree add trunk-work $BRANCH_EXTRACT
+
+cd trunk-work
+git checkout $BRANCH_EXTRACT
+
+# HEAD==ruby-src/trunk: first run; rewrite everything
+if [ $(git rev-parse HEAD) = $(git rev-parse ruby-src/trunk) ]; then
+	filter_range=
+else
+	old_head=$(git rev-parse HEAD)
+	echo "Updating '$BRANCH_EXTRACT'... HEAD was $old_head."
+	graftpoint="$(rev_to_sha1 ruby-src/trunk $(sha1_to_rev $old_head)) $old_head"
+	grep "^$graftpoint$" $(git rev-parse --git-common-dir)/info/grafts >/dev/null 2>&1 ||
+		echo "$graftpoint" >> $(git rev-parse --git-common-dir)/info/grafts
+	git reset -q --hard ruby-src/trunk
+	filter_range=$old_head..$BRANCH_EXTRACT
+fi
+
+echo "## Remove unrelated commits"
+git filter-branch -f --prune-empty --index-filter '
+	git rm --cached -qr --ignore-unmatch . &&
+	git reset -q $GIT_COMMIT -- ext/openssl test/openssl sample/openssl &&
+	git rm --cached -q --ignore-unmatch ext/openssl/depend ext/openssl/openssl.gemspec
+' -- $filter_range ||:
+
+echo "## Adjust path"
+git filter-branch -f --prune-empty --index-filter '
+	git ls-files --stage | \
+	    sed "s:\ttest/openssl:\ttest:" | \
+	    sed "s:\text/openssl/lib:\tlib:" | \
+	    sed "s:\text/openssl/sample:\tsample/openssl:" | \
+	    sed "s:\tsample/openssl:\tsample:" | \
+	    GIT_INDEX_FILE=$GIT_INDEX_FILE.new git update-index --index-info &&
+	mv "$GIT_INDEX_FILE.new" "$GIT_INDEX_FILE"
+	:
+' -- $filter_range ||:
+
+echo "## Fix author/committer email"
+git filter-branch -f --env-filter '
+	export GIT_AUTHOR_EMAIL=${GIT_AUTHOR_EMAIL/b2dd03c8-39d4-4d8f-98ff-823fe69b080e/ruby-lang.org}
+	export GIT_COMMITTER_EMAIL=${GIT_COMMITTER_EMAIL/b2dd03c8-39d4-4d8f-98ff-823fe69b080e/ruby-lang.org}
+' -- $filter_range ||:
+
+[ "$graftpoint" ] &&
+	sed -ie "/^$graftpoint$/d" $(git rev-parse --git-common-dir)/info/grafts