| package styles | |
| import ( | |
| "testing" | |
| "github.com/charmbracelet/x/ansi" | |
| "github.com/rivo/uniseg" | |
| "github.com/stretchr/testify/require" | |
| ) | |
| // TestCodespanPaddingIsOneCellWide guards the flicker regression from the | |
| // emoji-presentation variation selector: when the sentinel ended in U+FE0F, | |
| // ansi.StringWidth measured it as two cells wide while terminals rendered it | |
| // as one, and that mismatch made the frame differ repaint the line on every | |
| // frame. The sentinel must measure exactly one cell under every width | |
| // authority in play (glamour wraps with x/ansi, cells are stored with | |
| // uniseg). | |
| func TestCodespanPaddingIsOneCellWide(t *testing.T) { | |
| t.Parallel() | |
| require.Equal(t, 1, ansi.StringWidth(CodespanPadding), | |
| "codespan padding must budget one cell, or word wrap disagrees with the terminal") | |
| require.Equal(t, 1, uniseg.StringWidth(CodespanPadding), | |
| "codespan padding must occupy one screen cell") | |
| state := -1 | |
| cluster, _, w, _ := uniseg.FirstGraphemeClusterInString(CodespanPadding, state) | |
| require.Equal(t, CodespanPadding, cluster, "padding must be a single grapheme cluster") | |
| require.Equal(t, 1, w) | |
| require.NotEqual(t, "\u00a0", CodespanPadding, | |
| "sentinel must stay distinguishable from a real no-break space") | |
| } | |