feat: add converter for form patches to mutate patches (#44)

src/encoders/form-compat/compat-path.test-d.ts

@@ -0,0 +1,9 @@
+import {expectTypeOf, test} from 'vitest'
+
+import {type Path} from '../../path'
+import {type CompatPath} from './form-patch-types'
+
+test('compat paths', () => {
+  expectTypeOf<Path>().toMatchTypeOf<CompatPath | Readonly<CompatPath>>()
+  expectTypeOf<CompatPath>().toMatchTypeOf<Path>()
+})

src/encoders/form-compat/encode.ts

@@ -0,0 +1,65 @@
+import {at} from '../../mutations/creators'
+import {
+  diffMatchPatch,
+  insert,
+  set,
+  setIfMissing,
+  unset,
+} from '../../mutations/operations/creators'
+import {type NodePatch} from '../../mutations/types'
+import {type KeyedPathElement} from '../../path'
+import {
+  type CompatPath,
+  type FormPatchLike,
+  type FormPatchPath,
+} from './form-patch-types'
+
+function assertCompatible(formPatchPath: FormPatchPath): CompatPath {
+  if (formPatchPath.length === 0) {
+    return formPatchPath as never[]
+  }
+  for (const element of formPatchPath) {
+    if (Array.isArray(element)) {
+      throw new Error('Form patch paths cannot include arrays')
+    }
+  }
+  return formPatchPath as CompatPath
+}
+
+/**
+ * Convert a Sanity form patch (ie emitted from an input component) to a {@link NodePatch}
+ * Note the lack of encodeMutation here. Sanity forms never emit *mutations*, only patches
+ * @param patches - Array of {@link FormPatchLike}
+ * @internal
+ */
+export function encodePatches(patches: FormPatchLike[]): NodePatch[] {
+  return patches.map(formPatch => {
+    const path = assertCompatible(formPatch.path)
+    if (formPatch.type === 'unset') {
+      return at(path, unset())
+    }
+    if (formPatch.type === 'set') {
+      return at(path, set(formPatch.value))
+    }
+    if (formPatch.type === 'setIfMissing') {
+      return at(path, setIfMissing(formPatch.value))
+    }
+    if (formPatch.type === 'insert') {
+      const arrayPath = path.slice(0, -1)
+      const itemRef = formPatch.path[formPatch.path.length - 1]
+      return at(
+        arrayPath,
+        insert(
+          formPatch.items,
+          formPatch.position,
+          itemRef as number | KeyedPathElement,
+        ),
+      )
+    }
+    if (formPatch.type === 'diffMatchPatch') {
+      return at(path, diffMatchPatch(formPatch.value))
+    }
+    // @ts-expect-error - should be exhaustive
+    throw new Error(`Unknown patch type ${formPatch.type}`)
+  })
+}

src/encoders/form-compat/form-patch-types.ts

@@ -0,0 +1,150 @@
+/**
+ * Inlined from the 'sanity' package
+ */
+import {type ElementType} from '../../path'
+
+/**
+ * @deprecated
+ */
+export type FormPatchPathKeyedSegment = {_key: string}
+/**
+ * @deprecated
+ */
+export type FormPatchPathIndexTuple = [number | '', number | '']
+
+/**
+ * @deprecated
+ */
+export type FormPatchPathSegment =
+  | string
+  | number
+  | FormPatchPathKeyedSegment
+  | FormPatchPathIndexTuple
+
+/**
+ * @deprecated
+ */
+export type FormPatchPath = FormPatchPathSegment[]
+
+/**
+ * A variant of the FormPath type that never contains index tupes
+ */
+export type CompatPath = Exclude<
+  ElementType<FormPatchPath>,
+  FormPatchPathIndexTuple
+>[]
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export type FormPatchJSONValue =
+  | number
+  | string
+  | boolean
+  | {[key: string]: FormPatchJSONValue}
+  | FormPatchJSONValue[]
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export type FormPatchOrigin = 'remote' | 'local' | 'internal'
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export interface FormSetPatch {
+  path: FormPatchPath
+  type: 'set'
+  value: FormPatchJSONValue
+}
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export interface FormIncPatch {
+  path: FormPatchPath
+  type: 'inc'
+  value: FormPatchJSONValue
+}
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export interface FormDecPatch {
+  path: FormPatchPath
+  type: 'dec'
+  value: FormPatchJSONValue
+}
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export interface FormSetIfMissingPatch {
+  path: FormPatchPath
+  type: 'setIfMissing'
+  value: FormPatchJSONValue
+}
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export interface FormUnsetPatch {
+  path: FormPatchPath
+  type: 'unset'
+}
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export type FormInsertPatchPosition = 'before' | 'after'
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export interface FormInsertPatch {
+  path: FormPatchPath
+  type: 'insert'
+  position: FormInsertPatchPosition
+  items: FormPatchJSONValue[]
+}
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export interface FormDiffMatchPatch {
+  path: FormPatchPath
+  type: 'diffMatchPatch'
+  value: string
+}
+
+/**
+ *
+ * @internal
+ * @deprecated
+ */
+export type FormPatchLike =
+  | FormSetPatch
+  | FormSetIfMissingPatch
+  | FormUnsetPatch
+  | FormInsertPatch
+  | FormDiffMatchPatch

src/encoders/form-compat/index.ts

@@ -0,0 +1,2 @@
+export {encodePatches} from './encode'
+export * from './form-patch-types'

src/index.ts

@@ -1,11 +1,12 @@
 import * as CompactEncoder from './encoders/compact'
+import * as FormCompatEncoder from './encoders/form-compat'
 import * as SanityEncoder from './encoders/sanity'
 import * as CompactFormatter from './formatters/compact'
 
 export * from './mutations/autoKeys'
 export * from './mutations/creators'
 export * from './mutations/operations/creators'
-export {CompactEncoder, SanityEncoder}
+export {CompactEncoder, FormCompatEncoder, SanityEncoder}
 
 export {CompactFormatter}