Help with search bug

[Gapen]

I've forked vuetify trying my hand at solved an issue I raised a few weeks ago. #12732

I'm having a hard time in VDataTable.ts trying to find where the pagination changes as a user enters a search term.

Does anyone have an intuition on this matter?

function searchTableItems (
  items: any[],
  search: string | null,
  headersWithCustomFilters: DataTableHeader[],
  headersWithoutCustomFilters: DataTableHeader[],
  customFilter: DataTableFilterFunction
) {
  search = typeof search === 'string' ? search.trim() : null

  return items.filter(item => {
    // Headers with custom filters are evaluated whether or not a search term has been provided.
    // We need to match every filter to be included in the results.
    const matchesColumnFilters = headersWithCustomFilters.every(filterFn(item, search, defaultFilter))

    // Headers without custom filters are only filtered by the `search` property if it is defined.
    // We only need a single column to match the search term to be included in the results.
    const matchesSearchTerm = !search || headersWithoutCustomFilters.some(filterFn(item, search, customFilter))

    return matchesColumnFilters && matchesSearchTerm
  })
}

function filterFn (item: any, search: string | null, filter: DataTableFilterFunction) {
  return (header: DataTableHeader) => {
    const value = getObjectValueByPath(item, header.value)
    return header.filter ? header.filter(value, search, item) : filter(value, search, item)
  }
}

[Gapen]

I found where pagination changes on render, along with current-items and page-count.

render (): VNode {
    return this.$createElement(VData, {
      props: {
        ...this.$props,
        customFilter: this.customFilterWithColumns,
        customSort: this.customSortWithHeaders,
        itemsPerPage: this.computedItemsPerPage,
      },
      on: {
        'update:options': (v: DataOptions, old: DataOptions) => {
          this.internalGroupBy = v.groupBy || []
          !deepEqual(v, old) && this.$emit('update:options', v)
        },
        'update:page': (v: number) => this.$emit('update:page', v),
        'update:items-per-page': (v: number) => this.$emit('update:items-per-page', v),
        'update:sort-by': (v: string | string[]) => this.$emit('update:sort-by', v),
        'update:sort-desc': (v: boolean | boolean[]) => this.$emit('update:sort-desc', v),
        'update:group-by': (v: string | string[]) => this.$emit('update:group-by', v),
        'update:group-desc': (v: boolean | boolean[]) => this.$emit('update:group-desc', v),
        pagination: (v: DataPagination, old: DataPagination) => !deepEqual(v, old) && this.$emit('pagination', v),
        'current-items': (v: any[]) => {
          this.internalCurrentItems = v
          this.$emit('current-items', v)
        },
        'page-count': (v: number) => this.$emit('page-count', v),
      },
      scopedSlots: {
        default: this.genDefaultScopedSlot,
      },
    })
  }

[Gapen]

In VData.ts, in the paginateItems method:

paginateItems (items: any[]): any[] {
  // Make sure we don't try to display non-existant page if items suddenly change
  // TODO: Could possibly move this to pageStart/pageStop?
  if (this.serverItemsLength === -1 && items.length <= this.pageStart) {
    this.internalOptions.page = Math.max(1, this.internalOptions.page - 1)
  }

  return items.slice(this.pageStart, this.pageStop)
}

As of now, if the items.length is less than this.pageStart, Vuetify decrements the page by 1. This explains the behavior seen in my reproduction link. It would be more safe, and fix the bug if instead something like:

this.internalOptions.page = Math.max(1, Math.ceil(items.length/this.internalOptions.itemsPerPage))

were used. Should I submit a pull request? Should I write a test?