[diff++] Attempt to track moving of items

packages/@sanity/desk-tool/src/panes/documentPane/documentHistory/history/mendozaDiffer.ts

@@ -7,7 +7,10 @@ import {Transaction} from './types'
 
 export type Meta = {chunk: Chunk; transactionIndex: number} | null
 
-export type AnnotationExtractor = (value: Value<Meta>) => Annotation
+export type AnnotationExtractor = {
+  fromValue(value: Value<Meta>): Annotation
+  fromMeta(meta: Meta): Annotation
+}
 
 class ArrayContentWrapper implements ArrayInput<Annotation> {
   type: 'array' = 'array'
@@ -44,6 +47,11 @@ class ArrayContentWrapper implements ArrayInput<Annotation> {
       this.extractor
     ))
   }
+
+  annotationAt(idx: number): Annotation {
+    const meta = this.content.metas[idx]
+    return this.extractor.fromMeta(meta)
+  }
 }
 
 class ObjectContentWrapper implements ObjectInput<Annotation> {
@@ -131,7 +139,7 @@ class StringContentWrapper implements StringInput<Annotation> {
         // eslint-disable-next-line max-depth
         if (subEnd <= 0) break
 
-        push(part.value.slice(subStart, subEnd), this.extractor(part))
+        push(part.value.slice(subStart, subEnd), this.extractor.fromValue(part))
       }
 
       idx += length
@@ -146,7 +154,7 @@ function wrapValue(
   raw: unknown,
   extractor: AnnotationExtractor
 ): Input<Annotation> {
-  const annotation = extractor(value)
+  const annotation = extractor.fromValue(value)
 
   if (value.content) {
     switch (value.content.type) {
@@ -172,47 +180,38 @@ function wrapValue(
 function extractAnnotationForFromInput(
   timeline: Timeline,
   firstChunk: Chunk | null,
-  value: Value<Meta>
+  meta: Meta
 ): Annotation {
-  let tx: Transaction | null = null
-  let chunk: Chunk | null = null
-
-  if (value.endMeta) {
+  if (meta) {
     // The next transaction is where it disappeared:
-    const nextTxIndex = value.endMeta.transactionIndex + 1
-    tx = timeline.transactionByIndex(nextTxIndex)
-    if (!tx) return null
-
-    chunk = timeline.chunkByTransactionIndex(nextTxIndex, value.endMeta.chunk.index)
+    return annotationForTransactionIndex(timeline, meta.transactionIndex + 1, meta.chunk.index)
   } else if (firstChunk) {
-    // Otherwise, it must have disappeared in the first transaction:
-    tx = timeline.transactionByIndex(firstChunk.start)
-    chunk = firstChunk
+    return annotationForTransactionIndex(timeline, firstChunk.start, firstChunk.index)
   }
 
-  if (tx && chunk) {
-    return {
-      chunk,
-      timestamp: tx.timestamp,
-      author: tx.author
-    }
+  return null
+}
+
+function extractAnnotationForToInput(timeline: Timeline, meta: Meta): Annotation {
+  if (meta) {
+    return annotationForTransactionIndex(timeline, meta.transactionIndex, meta.chunk.index)
   }
 
   return null
 }
 
-function extractAnnotationForToInput(timeline: Timeline, value: Value<Meta>): Annotation {
-  if (value.startMeta) {
-    const tx = timeline.transactionByIndex(value.startMeta.transactionIndex)!
+function annotationForTransactionIndex(timeline: Timeline, idx: number, chunkIdx?: number) {
+  const tx = timeline.transactionByIndex(idx)
+  if (!tx) return null
 
-    return {
-      chunk: value.startMeta.chunk,
-      timestamp: tx.timestamp,
-      author: tx.author
-    }
-  }
+  const chunk = timeline.chunkByTransactionIndex(idx, chunkIdx)
+  if (!chunk) return null
 
-  return null
+  return {
+    chunk,
+    timestamp: tx.timestamp,
+    author: tx.author
+  }
 }
 
 export function diffValue(
@@ -223,9 +222,22 @@ export function diffValue(
   to: Value<Meta>,
   toRaw: unknown
 ): Diff<Annotation> {
-  const fromInput = wrapValue(from, fromRaw, value =>
-    extractAnnotationForFromInput(timeline, firstChunk, value)
-  )
-  const toInput = wrapValue(to, toRaw, value => extractAnnotationForToInput(timeline, value))
+  const fromInput = wrapValue(from, fromRaw, {
+    fromValue(value) {
+      return extractAnnotationForFromInput(timeline, firstChunk, value.endMeta)
+    },
+    fromMeta(meta) {
+      return extractAnnotationForFromInput(timeline, firstChunk, meta)
+    }
+  })
+
+  const toInput = wrapValue(to, toRaw, {
+    fromValue(value) {
+      return extractAnnotationForToInput(timeline, value.startMeta)
+    },
+    fromMeta(meta) {
+      return extractAnnotationForToInput(timeline, meta)
+    }
+  })
   return diffInput(fromInput, toInput)
 }

packages/@sanity/diff/src/calculate/diffArray.ts

@@ -96,7 +96,8 @@ function diffExactByPosition<A>(
       fromIndex: idx,
       toIndex: idx,
       hasMoved: false,
-      diff
+      diff,
+      annotation: toInput.annotationAt(idx)
     })
   }
 
@@ -117,7 +118,8 @@ function diffArrayByReinsert<A>(
       fromIndex: undefined,
       toIndex: idx,
       hasMoved: false,
-      diff: addedInput(input, undefined, options)
+      diff: addedInput(input, undefined, options),
+      annotation: input.annotation
     })
   }
 
@@ -128,7 +130,8 @@ function diffArrayByReinsert<A>(
       fromIndex: idx,
       toIndex: undefined,
       hasMoved: false,
-      diff: removedInput(input, undefined, options)
+      diff: removedInput(input, undefined, options),
+      annotation: input.annotation
     })
   }
 
@@ -162,7 +165,8 @@ function diffArrayByKey<A>(
       fromIndex,
       toIndex,
       hasMoved,
-      diff
+      diff,
+      annotation: toArray.annotationAt(toIndex)
     })
 
     if (diff.isChanged || fromIndex !== toIndex) {
@@ -195,7 +199,8 @@ function diffArrayByKey<A>(
       fromIndex,
       toIndex: undefined,
       hasMoved: false,
-      diff: removedInput(input, undefined, options)
+      diff: removedInput(input, undefined, options),
+      annotation: fromArray.annotationAt(fromIndex)
     })
 
     isChanged = true
@@ -209,7 +214,8 @@ function diffArrayByKey<A>(
         fromIndex: undefined,
         toIndex,
         hasMoved: false,
-        diff: addedInput(input, undefined, options)
+        diff: addedInput(input, undefined, options),
+        annotation: toArray.annotationAt(toIndex)
       })
     }
 
@@ -343,7 +349,8 @@ export function removedArray<A>(
           fromIndex: i,
           toIndex: undefined,
           hasMoved: false,
-          diff: removedInput(item, undefined, options)
+          diff: removedInput(item, undefined, options),
+          annotation: input.annotationAt(i)
         })
       }
 
@@ -373,7 +380,8 @@ export function addedArray<A>(
           fromIndex: undefined,
           toIndex: i,
           hasMoved: false,
-          diff: addedInput(item, undefined, options)
+          diff: addedInput(item, undefined, options),
+          annotation: input.annotationAt(i)
         })
       }
 

packages/@sanity/diff/src/inputWrappers/array.ts

@@ -24,4 +24,8 @@ export default class ArrayWrapper<A> implements ArrayInput<A> {
 
     return (this.elements[idx] = wrap(this.value[idx], this.annotation))
   }
+
+  annotationAt(): A {
+    return this.annotation
+  }
 }

packages/@sanity/diff/src/types.ts

@@ -47,6 +47,7 @@ export interface ArrayInput<A> extends BaseInput<A> {
   value: unknown[]
   length: number
   at(idx: number): Input<A>
+  annotationAt(idx: number): A
 }
 
 type AddedDiff<A, V> = {
@@ -147,4 +148,5 @@ export type ItemDiff<A> = {
   toIndex: number | undefined
   hasMoved: boolean
   diff: Diff<A>
+  annotation: A
 }

packages/@sanity/field/src/diff/changes/buildChangeList.ts

@@ -176,7 +176,8 @@ export function buildArrayChangeList(
       hasMoved: itemDiff.hasMoved,
       toIndex: itemDiff.toIndex,
       fromIndex: itemDiff.fromIndex,
-      annotation: itemDiff.diff.action === 'unchanged' ? undefined : itemDiff.diff.annotation
+      annotation:
+        itemDiff.diff.action === 'unchanged' ? itemDiff.annotation : itemDiff.diff.annotation
     })
 
     const attachItemDiff = (change: ChangeNode): ChangeNode => {

packages/@sanity/field/src/types/portableText/diff/helpers.ts

@@ -433,6 +433,7 @@ export function prepareDiffForPortableText(
                 fromValue: fromPseudoValue.children[0],
                 toValue: toPseudoValue.children[0]
               },
+              annotation: null,
               fromIndex: 0,
               toIndex: 0,
               hasMoved: false

packages/mendoza/src/incremental-patcher.ts

@@ -1,3 +1,8 @@
+/* eslint-disable default-case */
+/* eslint-disable class-methods-use-this */
+/* eslint-disable no-else-return */
+/* eslint-disable no-lonely-if */
+/* eslint-disable prefer-const */
 import {ObjectModel} from './object-model'
 import {RawPatch} from './patch'
 import {Patcher} from './internal-patcher'
@@ -25,6 +30,7 @@ export type ObjectContent<T> = {
 export type ArrayContent<T> = {
   type: 'array'
   elements: Value<T>[]
+  metas: T[]
 }
 
 export type StringContent<T> = {
@@ -71,7 +77,8 @@ class Model<T>
   asArray(value: Value<T>): ArrayContent<T> {
     if (!value.content) {
       let elements = (value.data as unknown[]).map(item => this.wrapWithMeta(item, value.startMeta))
-      value.content = {type: 'array', elements}
+      let metas = elements.map(() => this.meta)
+      value.content = {type: 'array', elements, metas}
     }
 
     return value.content as ArrayContent<T>
@@ -185,11 +192,14 @@ class Model<T>
   }
 
   copyArray(value: Value<T> | null): ArrayContent<T> {
-    let elements = value ? this.asArray(value).elements : []
+    let arr = value ? this.asArray(value) : null
+    let elements = arr ? arr.elements : []
+    let metas = arr ? arr.metas : []
 
     return {
       type: 'array',
-      elements
+      elements,
+      metas
     }
   }
 
@@ -203,11 +213,13 @@ class Model<T>
 
   arrayAppendValue(target: ArrayContent<T>, value: Value<T>): void {
     target.elements.push(value)
+    target.metas.push(this.meta)
   }
 
   arrayAppendSlice(target: ArrayContent<T>, source: Value<T>, left: number, right: number): void {
-    let slice = this.asArray(source).elements.slice(left, right)
-    target.elements.push(...slice)
+    let arr = this.asArray(source)
+    target.elements.push(...arr.elements.slice(left, right))
+    target.metas.push(...arr.metas.slice(left, right))
   }
 
   stringAppendValue(target: StringContent<T>, value: Value<T>): void {