test: add unit tests for getFieldByPath (#11533)

Adds unit tests for the new function `getFieldByPath` that was added
here https://github.com/payloadcms/payload/pull/11512

packages/payload/src/utilities/getFieldByPath.spec.ts

@@ -0,0 +1,108 @@
+import { assert } from 'ts-essentials'
+import { flattenAllFields } from './flattenAllFields.js'
+import { getFieldByPath } from './getFieldByPath.js'
+import type { FlattenedArrayField, FlattenedGroupField } from '../fields/config/types.js'
+
+const fields = flattenAllFields({
+  fields: [
+    {
+      type: 'text',
+      name: 'text',
+    },
+    {
+      type: 'text',
+      name: 'textLocalized',
+      localized: true,
+    },
+    {
+      type: 'array',
+      name: 'array',
+      fields: [
+        {
+          name: 'text',
+          type: 'text',
+        },
+        {
+          name: 'textLocalized',
+          localized: true,
+          type: 'text',
+        },
+        {
+          name: 'group',
+          type: 'group',
+          fields: [
+            {
+              name: 'text',
+              type: 'text',
+            },
+          ],
+        },
+      ],
+    },
+    {
+      type: 'tabs',
+      tabs: [
+        {
+          name: 'tab',
+          fields: [
+            {
+              type: 'array',
+              name: 'localizedArray',
+              localized: true,
+              fields: [
+                {
+                  name: 'text',
+                  type: 'text',
+                },
+              ],
+            },
+          ],
+        },
+      ],
+    },
+  ],
+})
+
+describe('getFieldByPath', () => {
+  it('asserts getFieldByPath', () => {
+    const assert_1 = getFieldByPath({ fields, path: 'text' })
+    assert(assert_1)
+    expect(assert_1.field).toBe(fields[0])
+    expect(assert_1.pathHasLocalized).toBe(false)
+
+    const assert_2 = getFieldByPath({ fields, path: 'textLocalized' })
+    assert(assert_2)
+    expect(assert_2.field).toBe(fields[1])
+    expect(assert_2.pathHasLocalized).toBe(true)
+    expect(assert_2.localizedPath).toBe('textLocalized.<locale>')
+
+    const arrayField = fields[2] as FlattenedArrayField
+    const assert_3 = getFieldByPath({ fields, path: 'array' })
+    assert(assert_3)
+    expect(assert_3.field).toBe(arrayField)
+    expect(assert_3.pathHasLocalized).toBe(false)
+
+    const assert_4 = getFieldByPath({ fields, path: 'array.text' })
+    assert(assert_4)
+    expect(assert_4.field).toBe(arrayField.flattenedFields[0])
+    expect(assert_4.pathHasLocalized).toBe(false)
+
+    const assert_5 = getFieldByPath({ fields, path: 'array.textLocalized' })
+    assert(assert_5)
+    expect(assert_5.field).toBe(arrayField.flattenedFields[1])
+    expect(assert_5.pathHasLocalized).toBe(true)
+    expect(assert_5.localizedPath).toBe('array.textLocalized.<locale>')
+
+    const groupWithinArray = arrayField.flattenedFields[2] as FlattenedGroupField
+    const assert_6 = getFieldByPath({ fields, path: 'array.group.text' })
+    assert(assert_6)
+    expect(assert_6.field).toBe(groupWithinArray.flattenedFields[0])
+    expect(assert_6.pathHasLocalized).toBe(false)
+
+    const assert_7 = getFieldByPath({ fields, path: 'tab.localizedArray.text' })
+    assert(assert_7)
+    expect(assert_7.field).toBe((fields[3] as any).flattenedFields[0].flattenedFields[0])
+    expect(assert_7.pathHasLocalized).toBe(true)
+    expect(assert_7.localizedPath).toBe('tab.localizedArray.<locale>.text')
+  })
+})