t4200 (rerere): modernize style
Guard all test code with test_expect_success to make the
script easier to follow. While at it, pick some other nits:
- use test_tick (more than we have to, to be realistic);
- 'single quotes' and \escaped HERE documents where possible
simplify review for escaping problems;
- omit whitespace after >redirection operators for
consistency with other tests;
- use "update-index --refresh" instead of testing that
"ls-files -u" output is empty, since the former produces
nicer output on failure;
- compare to expected nonempty "ls-files -u" output instead
of counting lines when it is expected to be nonempty.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>