fix(toc): keep active outline entry visible

test/page-toc-scrollspy.test.tsadded+22-0

Changes to test/page-toc-scrollspy.test.ts

		@@ -0,0 +1,22 @@
	1	+import { describe, expect, test } from 'bun:test'
	2	+import { readFileSync } from 'node:fs'
	3	+import { join } from 'node:path'
	4	+
	5	+const root = join(import.meta.dir, '..')
	6	+const pageToc = readFileSync(join(root, 'packages/bunpress/src/templates/page-toc.stx'), 'utf8')
	7	+const pageOutline = readFileSync(join(root, 'packages/bunpress/src/templates/page-outline.stx'), 'utf8')
	8	+
	9	+describe('page outline scrollspy', () => {
	10	+ test('tracks both responsive outline variants', () => {
	11	+ expect(pageToc).toContain("document.querySelectorAll('.page-toc a, .bp-local-outline-items a')")
	12	+ expect(pageOutline).toContain('.bp-local-outline-items a.active')
	13	+ })
	14	+
	15	+ test('keeps the active link inside the visible outline viewport', () => {
	16	+ expect(pageToc).toContain('function keepActiveLinkVisible(activeLink)')
	17	+ expect(pageToc).toContain("activeLink.closest('.BPDocAside') || activeLink.closest('.bp-local-outline-items')")
	18	+ expect(pageToc).toContain('outlineViewport.scrollTop += linkRect.top - viewportRect.top - inset')
	19	+ expect(pageToc).toContain('outlineViewport.scrollTop += linkRect.bottom - viewportRect.bottom + inset')
	20	+ expect(pageToc).toContain('keepActiveLinkVisible(link)')
	21	+ })
	22	+})