test_that("read_yaff() and write_yaff()", {
    yaff_file <- system.file("fonts/fixed/4x6.yaff.gz", package = "bittermelon")
    yaff <- read_yaff(yaff_file)
    expect_true(is_bm_font(yaff))

    expect_true(any(grepl("Send bug reports to Markus Kuhn",
                          attr(yaff, "comments"))))

    expect_equal(attr(yaff, "properties")$name,
                 "Fixed Medium 6")
    expect_equal(attr(yaff, "properties")[["source-name"]],
                 "4x6.bdf")

    plus_cp <- name2ucp("PLUS SIGN") # code point U+002B
    expect_equal(length(read_yaff(textConnection(""))), 0L)

    f <- tempfile(fileext = ".yaff.gz")
    write_yaff(yaff, gzfile(f))
    yaff2 <- read_yaff(f)
    unlink(f)

    expect_equal(yaff[[plus_cp]], yaff2[[plus_cp]])
})

test_that("is_combining_character()", {
    expect_false(is_combining_character(str2ucp("a")))
    expect_true(is_combining_character("U+0300"))
    expect_true(is_combining_character("U+20DD"))
})