humanspeak / svelte-headless-table / 36576391648

90%

Build Type

push

github

Committed by web-flow

Commit Message

fix(virtual-scroll): viewportRange names row 1 at the top under a sticky header (#336)

`viewportRange` subtracts two DOM measurements: how much of the viewport
the header covers, and where the rows begin. The first was re-read on
every scroll, the second only when the first rendered row mounted or
resized, and only through `measureRowAction`. Whenever they disagreed by
a row's height, a "rows N-M" footer read 2 at the top of the table.

- Read both together: on scroll, when the header or the container
  resizes, and when the container mounts. Rows and header mount before
  their container, so the first reading used to depend on a
  ResizeObserver callback that a window which is not being rendered
  never delivers.
- When no row is measured with `measureRowAction`, take the rows to
  begin where the header ends instead of at the container's origin.
- Measure from inside the container's border rather than its outer edge.
- Locate the first row before recording its height, so the spacer it is
  compared against is the one the DOM is showing.

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

Coverage Stats

663 of 795 branches covered (83.4%)

Branch coverage included in aggregate %.

33 of 42 new or added lines in 1 file covered. (78.57%)

1 existing line in 1 file now uncovered.

1653 of 1779 relevant lines covered (92.92%)

28789.41 hits per line