'git-cat-file commit branch | sed 1,2d >actual &&
diff -u expect actual'
+###
+### series F
+###
+
+old_branch=`git-rev-parse --verify branch^0`
+test_tick
+cat >input <<INPUT_END
+commit refs/heads/branch
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data <<COMMIT
+losing things already?
+COMMIT
+
+from refs/heads/branch~1
+
+reset refs/heads/other
+from refs/heads/branch
+
+INPUT_END
+test_expect_success \
+ 'F: non-fast-forward update skips' \
+ 'if git-fast-import <input
+ then
+ echo BAD gfi did not fail
+ return 1
+ else
+ if test $old_branch = `git-rev-parse --verify branch^0`
+ then
+ : branch unaffected and failure returned
+ return 0
+ else
+ echo BAD gfi changed branch $old_branch
+ return 1
+ fi
+ fi
+ '
+test_expect_success \
+ 'F: verify pack' \
+ 'for p in .git/objects/pack/*.pack;do git-verify-pack $p||exit;done'
+
+cat >expect <<EOF
+tree `git-rev-parse branch~1^{tree}`
+parent `git-rev-parse branch~1`
+author $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+
+losing things already?
+EOF
+test_expect_success \
+ 'F: verify other commit' \
+ 'git-cat-file commit other >actual &&
+ diff -u expect actual'
+
+###
+### series G
+###
+
+old_branch=`git-rev-parse --verify branch^0`
+test_tick
+cat >input <<INPUT_END
+commit refs/heads/branch
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data <<COMMIT
+losing things already?
+COMMIT
+
+from refs/heads/branch~1
+
+INPUT_END
+test_expect_success \
+ 'G: non-fast-forward update forced' \
+ 'git-fast-import --force <input'
+test_expect_success \
+ 'G: verify pack' \
+ 'for p in .git/objects/pack/*.pack;do git-verify-pack $p||exit;done'
+test_expect_success \
+ 'G: branch changed, but logged' \
+ 'test $old_branch != `git-rev-parse --verify branch^0` &&
+ test $old_branch = `git-rev-parse --verify branch@{1}`'
+
test_done