smooth-scroll-into-view-if-needed/dist/index.cjs.map

Ponyfill for smooth scrolling elements into view (if needed!)

{"version":3,"file":"index.cjs","sources":["../src/index.ts"],"sourcesContent":["import scrollIntoView, {\n  Options,\n  StandardBehaviorOptions,\n  CustomBehaviorOptions,\n} from 'scroll-into-view-if-needed'\n\nexport interface CustomEasing {\n  (t: number): number\n}\n\ntype OnScrollChangeCallback = (scrollState: {\n  target: Element\n  elapsed: number\n  value: number\n  left: number\n  top: number\n}) => void\n\nexport type SmoothBehaviorOptions = Options & {\n  behavior?: 'smooth'\n  duration?: number\n  ease?: CustomEasing\n  onScrollChange?: OnScrollChangeCallback\n}\n\n// Memoize so we're much more friendly to non-dom envs\nlet memoizedNow: () => number\nconst now = () => {\n  if (!memoizedNow) {\n    memoizedNow =\n      'performance' in window ? performance.now.bind(performance) : Date.now\n  }\n  return memoizedNow()\n}\n\ntype SmoothScrollAction = {\n  el: Element\n  // [start, end] tuples of the distance animated\n  left: [number, number]\n  top: [number, number]\n}\n\ntype Context = {\n  scrollable: Element\n  method: (elapsed: number, value: number, x: number, y: number) => void\n  startTime: number\n  startX: number\n  startY: number\n  x: number\n  y: number\n  duration: number\n  ease: CustomEasing\n  cb: Function\n}\nfunction step(context: Context) {\n  const time = now()\n  const elapsed = Math.min((time - context.startTime) / context.duration, 1)\n  // apply easing to elapsed time\n  const value = context.ease(elapsed)\n\n  const currentX = context.startX + (context.x - context.startX) * value\n  const currentY = context.startY + (context.y - context.startY) * value\n\n  context.method(currentX, currentY, elapsed, value)\n\n  // scroll more if we have not reached our destination\n  if (currentX !== context.x || currentY !== context.y) {\n    requestAnimationFrame(() => step(context))\n  } else {\n    // If nothing left to scroll lets fire the callback\n    context.cb()\n  }\n}\n\nfunction smoothScroll(\n  el: Element,\n  x: number,\n  y: number,\n  duration = 600,\n  ease: CustomEasing = (t) => 1 + --t * t * t * t * t,\n  cb: Function,\n  onScrollChange?: OnScrollChangeCallback\n) {\n  // define scroll context\n  const scrollable = el\n  const startX = el.scrollLeft\n  const startY = el.scrollTop\n  const method = (x: number, y: number, elapsed: number, value: number) => {\n    // @TODO use Element.scroll if it exists, as it is potentially better performing\n    // use ceil to include the the fractional part of the number for the scrolling\n    const left = Math.ceil(x)\n    const top = Math.ceil(y)\n\n    el.scrollLeft = left\n    el.scrollTop = top\n\n    onScrollChange?.({\n      target: el,\n      elapsed,\n      value,\n      left,\n      top,\n    })\n  }\n\n  // scroll looping over a frame if needed\n  step({\n    scrollable: scrollable,\n    method: method,\n    startTime: now(),\n    startX: startX,\n    startY: startY,\n    x: x,\n    y: y,\n    duration,\n    ease,\n    cb,\n  })\n}\n\nconst shouldSmoothScroll = <T>(options: any): options is T => {\n  return (options && !options.behavior) || options.behavior === 'smooth'\n}\n\nfunction scroll(target: Element, options?: SmoothBehaviorOptions): Promise<any>\nfunction scroll<T>(target: Element, options: CustomBehaviorOptions<T>): T\nfunction scroll(target: Element, options: StandardBehaviorOptions): void\nfunction scroll<T>(target: Element, options?: any) {\n  const overrides = options || {}\n  if (shouldSmoothScroll<SmoothBehaviorOptions>(overrides)) {\n    return scrollIntoView<Promise<SmoothScrollAction[]>>(target, {\n      block: overrides.block,\n      inline: overrides.inline,\n      scrollMode: overrides.scrollMode,\n      boundary: overrides.boundary,\n      skipOverflowHiddenElements: overrides.skipOverflowHiddenElements,\n      behavior: (actions) =>\n        Promise.all(\n          actions.reduce(\n            (results: Promise<SmoothScrollAction>[], { el, left, top }) => {\n              const startLeft = el.scrollLeft\n              const startTop = el.scrollTop\n              if (startLeft === left && startTop === top) {\n                return results\n              }\n\n              return [\n                ...results,\n                new Promise((resolve) => {\n                  return smoothScroll(\n                    el,\n                    left,\n                    top,\n                    overrides.duration,\n                    overrides.ease,\n                    () =>\n                      resolve({\n                        el,\n                        left: [startLeft, left],\n                        top: [startTop, top],\n                      }),\n                    overrides.onScrollChange\n                  )\n                }),\n              ]\n            },\n            []\n          )\n        ),\n    })\n  }\n\n  return Promise.resolve(scrollIntoView<T>(target, options))\n}\n\n// re-assign here makes the flowtype generation work\nconst smoothScrollIntoView = scroll\n\nexport default smoothScrollIntoView\n"],"names":["_interopDefaultCompat","e","default","scrollIntoView__default","require","memoizedNow","now","window","performance","bind","Date","step","context","time","elapsed","Math","min","startTime","duration","value","ease","currentX","startX","x","currentY","startY","y","method","requestAnimationFrame","cb","smoothScroll","el","arguments","length","undefined","t","onScrollChange","scrollable","scrollLeft","scrollTop","left","ceil","top","target","shouldSmoothScroll","options","behavior","smoothScrollIntoView","overrides","scrollIntoView","block","inline","scrollMode","boundary","skipOverflowHiddenElements","actions","Promise","all","reduce","results","_ref","startLeft","startTop","resolve","module","exports"],"mappings":"AA0BA,aAAA,SAAAA,EAAAC,GAAA,OAAAA,GAAA,iBAAAA,GAAA,YAAAA,EAAAA,EAAA,CAAAC,QAAAD,EAAA,CAAA,IAAAE,EAAAH,EAAAI,QAAA,+BAAA,IAAIC,EACJ,MAAMC,EAAMA,KACLD,IACHA,EACE,gBAAiBE,OAASC,YAAYF,IAAIG,KAAKD,aAAeE,KAAKJ,KAEhED,KAsBT,SAASM,EAAKC,GACZ,MAAMC,EAAOP,IACPQ,EAAUC,KAAKC,KAAKH,EAAOD,EAAQK,WAAaL,EAAQM,SAAU,GAElEC,EAAQP,EAAQQ,KAAKN,GAErBO,EAAWT,EAAQU,QAAUV,EAAQW,EAAIX,EAAQU,QAAUH,EAC3DK,EAAWZ,EAAQa,QAAUb,EAAQc,EAAId,EAAQa,QAAUN,EAEjEP,EAAQe,OAAON,EAAUG,EAAUV,EAASK,GAGxCE,IAAaT,EAAQW,GAAKC,IAAaZ,EAAQc,EAC3BE,uBAAA,IAAMjB,EAAKC,KAGjCA,EAAQiB,IAEZ,CAEA,SAASC,EACPC,EACAR,EACAG,GAKA,IAJAR,EAAAc,UAAAC,OAAA,QAAAC,IAAAF,UAAA,GAAAA,UAAA,GAAW,IACXZ,EAAqBY,UAAAC,eAAAC,IAAAF,UAAA,GAAAA,UAAA,GAACG,GAAM,IAAMA,EAAIA,EAAIA,EAAIA,EAAIA,EAClDN,yCACAO,EACAJ,UAAAC,OAAAD,EAAAA,kBAAAE,EAEA,MAAMG,EAAaN,EACbT,EAASS,EAAGO,WACZb,EAASM,EAAGQ,UAoBb5B,EAAA,CACH0B,aACAV,OArBaA,CAACJ,EAAWG,EAAWZ,EAAiBK,KAG/C,MAAAqB,EAAOzB,KAAK0B,KAAKlB,GACjBmB,EAAM3B,KAAK0B,KAAKf,GAEtBK,EAAGO,WAAaE,EAChBT,EAAGQ,UAAYG,EAEE,MAAAN,GAAAA,EAAA,CACfO,OAAQZ,EACRjB,UACAK,QACAqB,OACAE,OACF,EAOAzB,UAAWX,IACXgB,SACAG,SACAF,IACAG,IACAR,WACAE,OACAS,MAEJ,CAEA,MAAMe,EAAyBC,GACrBA,IAAYA,EAAQC,UAAkC,WAArBD,EAAQC,SAuDnD,MAAMC,EAjDN,SAAmBJ,EAAiBE,GAC5B,MAAAG,EAAYH,GAAW,GACzB,OAAAD,EAA0CI,GACrCC,EAAAA,QAA8CN,EAAQ,CAC3DO,MAAOF,EAAUE,MACjBC,OAAQH,EAAUG,OAClBC,WAAYJ,EAAUI,WACtBC,SAAUL,EAAUK,SACpBC,2BAA4BN,EAAUM,2BACtCR,SAAWS,GACTC,QAAQC,IACNF,EAAQG,QACN,CAACC,EAAwCC,KAAsB,IAAtB7B,GAAEA,EAAIS,KAAAA,EAAAE,IAAMA,GAAUkB,EAC7D,MAAMC,EAAY9B,EAAGO,WACfwB,EAAW/B,EAAGQ,UAChB,OAAAsB,IAAcrB,GAAQsB,IAAapB,EAC9BiB,EAGF,IACFA,EACH,IAAIH,SAASO,GACJjC,EACLC,EACAS,EACAE,EACAM,EAAU9B,SACV8B,EAAU5B,MACV,IACE2C,EAAQ,CACNhC,KACAS,KAAM,CAACqB,EAAWrB,GAClBE,IAAK,CAACoB,EAAUpB,MAEpBM,EAAUZ,kBAGhB,GAEF,OAMHoB,QAAQO,QAAQd,EAAAA,QAAkBN,EAAQE,GACnD,EAG6BmB,OAAAC,QAAAlB"}