Function resolveSplitPaneWidths

src/ui/diff/codeColumns.ts:84–93

(width: number)

/** Split-view panes reserve one rail column on the left and one separator column in the middle. */
export function resolveSplitPaneWidths(width: number) {
  const usableWidth = Math.max(0, width - DIFF_RAIL_PREFIX_WIDTH - DIFF_SPLIT_SEPARATOR_WIDTH);
  const leftWidth = Math.max(0, DIFF_RAIL_PREFIX_WIDTH + Math.floor(usableWidth / 2));
  const rightWidth = Math.max(
    0,
    DIFF_SPLIT_SEPARATOR_WIDTH + usableWidth - Math.floor(usableWidth / 2),
  );

  return { leftWidth, rightWidth };
}

/** Resolve the split-cell gutter and code viewport after the rail prefix. */
export function resolveSplitCellGeometry(