Add unittest

Add unittest

[   23s] + ./compiletest
[   23s]
[   23s] running 1 test
[   23s] test ui ... ignored
[   23s]
[   23s] test result: ok. 0 passed; 0 failed; 1 ignored; 0 measured; 0 filtered out; finished in 0.00s
[   23s]
[   23s] + for unit_test in '${unit_test_list}'
[   23s] + ./test
[   23s]
[   23s] running 37 tests
[   23s] test test_append_tokens ... ok
[   23s] test test_advanced ... ok
[   23s] test test_box_str ... ok
[   23s] test test_btreeset_repetition ... ok
[   23s] test test_array ... ok
[   23s] test test_char ... ok
[   23s] test test_cow ... ok
[   23s] test test_closure ... ok
[   23s] test test_duplicate ... ok
[   23s] test test_duplicate_name_repetition ... ok
[   23s] test test_duplicate_name_repetition_no_copy ... ok
[   23s] test test_empty_quote ... ok
[   23s] test test_fancy_repetition ... ok
[   23s] test test_floating ... ok
[   23s] test test_format_ident ... ok
[   23s] test test_format_ident_strip_raw ... ok
[   23s] test test_ident ... ok
[   23s] test test_inner_attr ... ok
[   23s] test test_inner_block_comment ... ok
[   23s] test test_inner_line_comment ... ok
[   23s] test test_integer ... ok
[   23s] test test_interpolated_literal ... ok
[   23s] test test_iter ... ok
[   23s] test test_nested_fancy_repetition ... ok
[   23s] test test_nonrep_in_repetition ... ok
[   23s] test test_outer_attr ... ok
[   23s] test test_outer_block_comment ... ok
[   23s] test test_outer_line_comment ... ok
[   23s] test test_quote_impl ... ok
[   23s] test test_quote_raw_id ... ok
[   23s] test test_quote_spanned_impl ... ok
[   23s] test test_star_after_repetition ... ok
[   23s] test test_str ... ok
[   23s] test test_string ... ok
[   23s] test test_substitution ... ok
[   23s] test test_underscore ... ok
[   23s] test test_variable_name_conflict ... ok
[   23s]
[   23s] test result: ok. 37 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.05s