'
+test_expect_success 'use --edit-description' '
+ write_script editor <<-\EOF &&
+ echo "New contents" >"$1"
+ EOF
+ EDITOR=./editor git branch --edit-description &&
+ write_script editor <<-\EOF &&
+ git stripspace -s <"$1" >"EDITOR_OUTPUT"
+ EOF
+ EDITOR=./editor git branch --edit-description &&
+ echo "New contents" >expect &&
+ test_cmp EDITOR_OUTPUT expect
+'
+
+test_expect_success 'detect typo in branch name when using --edit-description' '
+ write_script editor <<-\EOF &&
+ echo "New contents" >"$1"
+ EOF
+ (
+ EDITOR=./editor &&
+ export EDITOR &&
+ test_must_fail git branch --edit-description no-such-branch
+ )
+'
+
+test_expect_success 'refuse --edit-description on unborn branch for now' '
+ write_script editor <<-\EOF &&
+ echo "New contents" >"$1"
+ EOF
+ git checkout --orphan unborn &&
+ (
+ EDITOR=./editor &&
+ export EDITOR &&
+ test_must_fail git branch --edit-description
+ )
+'
+
+ test_expect_success '--merged catches invalid object names' '
+ test_must_fail git branch --merged 0000000000000000000000000000000000000000
+ '
+
test_done