[base] Optimize and move collate function to draft-utils (#1422)

This optimizes how we collate drafts and published into a single entry for display in document lists. Also moved the collate function into the common draftUtils package so that we can re-use it anywhere else it's needed.

The numbers I got when collating a list of 10474 items locally (average of around 10 samples):

*Before*: 142.15 ms
*After*: 18.47 ms

packages/@sanity/base/src/util/draftUtils.js

@@ -42,15 +42,19 @@ export function createPublishedFrom(document) {
   }
 }
 
+// Takes a list of documents and collates draft/published pairs into single entries
+// {id: <published id>, draft?: <draft document>, published?: <published document>}
+export function collate(documents) {
+  const byId = documents.reduce((res, doc) => {
+    const id = getPublishedId(doc._id)
+    const entry = res[id] || (res[id] = {id})
+    entry[id === doc._id ? 'published' : 'draft'] = doc
+    return res
+  }, Object.create(null))
+  return Object.values(byId)
+}
+
 // Removes published documents that also has a draft
 export function removeDupes(documents) {
-  const drafts = documents.map(doc => doc._id).filter(isDraftId)
-
-  return documents.filter(doc => {
-    const draftId = getDraftId(doc._id)
-    const publishedId = getPublishedId(doc._id)
-    const hasDraft = drafts.includes(draftId)
-    const isPublished = doc._id === publishedId
-    return isPublished ? !hasDraft : true
-  })
+  return collate(documents).map(entry => entry.draft || entry.published)
 }

packages/@sanity/base/test/draftUtils.test.js

@@ -0,0 +1,23 @@
+import {collate, removeDupes} from '../src/util/draftUtils'
+
+test('collate()', () => {
+  const foo = {_id: 'foo'}
+  const fooDraft = {_id: 'drafts.foo'}
+  const barDraft = {_id: 'drafts.bar'}
+  const baz = {_id: 'baz'}
+
+  expect(collate([foo, fooDraft, barDraft, baz])).toEqual([
+    {id: 'foo', draft: fooDraft, published: foo},
+    {id: 'bar', draft: barDraft},
+    {id: 'baz', published: baz}
+  ])
+})
+
+test('removeDupes()', () => {
+  const foo = {_id: 'foo'}
+  const fooDraft = {_id: 'drafts.foo'}
+  const barDraft = {_id: 'drafts.bar'}
+  const baz = {_id: 'baz'}
+
+  expect(removeDupes([foo, fooDraft, barDraft, baz])).toEqual([fooDraft, barDraft, baz])
+})

packages/@sanity/desk-tool/src/pane/DocumentsListPane.js

@@ -1,6 +1,5 @@
 import React from 'react'
 import PropTypes from 'prop-types'
-import {partition} from 'lodash'
 import {withRouterHOC} from 'part:@sanity/base/router'
 import schema from 'part:@sanity/base/schema'
 import PlusIcon from 'part:@sanity/base/plus-icon'
@@ -9,12 +8,7 @@ import DefaultPane from 'part:@sanity/components/panes/default'
 import QueryContainer from 'part:@sanity/base/query-container'
 import Snackbar from 'part:@sanity/components/snackbar/default'
 import Spinner from 'part:@sanity/components/loading/spinner'
-import {
-  getPublishedId,
-  isDraftId,
-  isPublishedId,
-  getDraftId
-} from 'part:@sanity/base/util/draft-utils'
+import {collate, getPublishedId} from 'part:@sanity/base/util/draft-utils'
 import {isActionEnabled} from 'part:@sanity/base/util/document-action-utils'
 
 import {combineLatest} from 'rxjs'
@@ -28,15 +22,14 @@ import {map, tap} from 'rxjs/operators'
 const DEFAULT_ORDERING = [{field: '_createdAt', direction: 'desc'}]
 
 function removePublishedWithDrafts(documents) {
-  const [draftIds, publishedIds] = partition(documents.map(doc => doc._id), isDraftId)
-
-  return documents
-    .map(doc => ({
+  return collate(documents).map(entry => {
+    const doc = entry.draft || entry.published
+    return {
       ...doc,
-      hasPublished: publishedIds.includes(getPublishedId(doc._id)),
-      hasDraft: draftIds.includes(getDraftId(doc._id))
-    }))
-    .filter(doc => !(isPublishedId(doc._id) && doc.hasDraft))
+      hasPublished: !!entry.published,
+      hasDraft: !!entry.draft
+    }
+  })
 }
 
 function getDocumentKey(document) {