Unuse range

src/core/cache.spec.ts

@@ -10,7 +10,14 @@ import {
  hasUnmeasuredItemsInRange,
 } from "./cache";
 import type { Writeable } from "./types";
-import { range } from "./utils";
+
+const range = <T>(length: number, cb: (i: number) => T): T[] => {
+ const array: T[] = [];
+ for (let i = 0; i < length; i++) {
+ array.push(cb(i));
+ }
+ return array;
+};
 
 const sum = (cache: readonly number[]): number => {
  return cache.reduce((acc, c) => acc + c, 0);

src/core/cache.ts

@@ -1,5 +1,5 @@
 import type { DeepReadonly, Writeable } from "./types";
-import { exists, max, median, min, range } from "./utils";
+import { exists, max, median, min } from "./utils";
 
 export const UNCACHED = -1;
 
@@ -138,29 +138,28 @@ export const resetCache = (
  itemSize: number,
  cache?: Cache
 ): Cache => {
+ const sizes: number[] = [];
+ const offsets: number[] = [];
+ for (let i = 0; i < length; i++) {
+ const size = cache && cache._sizes[i];
+ sizes.push(exists(size) ? size : UNCACHED);
+
+ if (i === 0) {
+ // first offset must be 0
+ offsets.push(0);
+ } else {
+ const offset = cache && cache._offsets[i];
+ offsets.push(exists(offset) ? offset : UNCACHED);
+ }
+ }
+
  return {
  _defaultItemSize: cache ? cache._defaultItemSize : itemSize,
  _length: length,
  _measuredOffsetIndex: cache
  ? min(cache._measuredOffsetIndex, length - 1)
  : 0,
- _sizes: range(length, (i) => {
- const size = cache && cache._sizes[i];
- if (exists(size)) {
- return size;
- }
- return UNCACHED;
- }),
- _offsets: range(length, (i) => {
- if (i === 0) {
- // first offset must be 0
- return 0;
- }
- const offset = cache && cache._offsets[i];
- if (exists(offset)) {
- return offset;
- }
- return UNCACHED;
- }),
+ _sizes: sizes,
+ _offsets: offsets,
  };
 };

src/core/utils.ts

@@ -7,14 +7,6 @@ export const timeout = setTimeout;
 
 export const exists = <T>(v: T): v is Exclude<T, null | undefined> => v != null;
 
-export const range = <T>(length: number, cb: (i: number) => T): T[] => {
- const array: T[] = [];
- for (let i = 0; i < length; i++) {
- array.push(cb(i));
- }
- return array;
-};
-
 export const median = (arr: number[]): number => {
  const s = [...arr].sort((a, b) => a - b);
  const mid = (arr.length / 2) | 0;