feat: support nested groups

package.json

@@ -83,7 +83,7 @@
 	},
 	"devDependencies": {
 		"@prismicio/mock": "^0.3.1",
-		"@prismicio/types-internal": "^2.4.0",
+		"@prismicio/types-internal": "^2.5.0-alpha.4",
 		"@size-limit/preset-small-lib": "^9.0.0",
 		"@trivago/prettier-plugin-sort-imports": "^4.2.0",
 		"@typescript-eslint/eslint-plugin": "^6.7.4",

src/helpers/isFilled.ts

@@ -3,7 +3,7 @@ import type { ContentRelationshipField } from "../types/value/contentRelationshi
 import type { DateField } from "../types/value/date";
 import type { AnyOEmbed, EmbedField } from "../types/value/embed";
 import type { GeoPointField } from "../types/value/geoPoint";
-import type { GroupField } from "../types/value/group";
+import type { GroupField, NestedGroupField } from "../types/value/group";
 import type { ImageField, ImageFieldImage } from "../types/value/image";
 import type { IntegrationField } from "../types/value/integration";
 import type { KeyTextField } from "../types/value/keyText";
@@ -273,7 +273,9 @@ export const integrationFields = integrationField;
  *
  * @returns `true` if `group` contains at least one item, `false` otherwise.
  */
-export const group = <Fields extends Record<string, AnyRegularField>>(
+export const group = <
+	Fields extends Record<string, AnyRegularField | NestedGroupField>,
+>(
 	group: GroupField<Fields> | null | undefined,
 ): group is GroupField<Fields, "filled"> => {
 	return isNonNullish(group) && isNonEmptyArray(group);

src/index.ts

@@ -221,7 +221,7 @@ export type { GeoPointField } from "./types/value/geoPoint";
 type IntegrationFields = IntegrationField;
 export { IntegrationField, IntegrationFields };
 
-export type { GroupField } from "./types/value/group";
+export type { GroupField, NestedGroupField } from "./types/value/group";
 
 export type { SliceZone } from "./types/value/sliceZone";
 export type { Slice } from "./types/value/slice";
@@ -283,7 +283,10 @@ export {
 	CustomTypeModelIntegrationField,
 	CustomTypeModelIntegrationFieldsField,
 };
-export type { CustomTypeModelGroupField } from "./types/model/group";
+export type {
+	CustomTypeModelGroupField,
+	CustomTypeModelNestedGroupField,
+} from "./types/model/group";
 export type {
 	CustomTypeModelSliceZoneField,
 	CustomTypeModelSliceLabel,
@@ -304,6 +307,7 @@ export type { CustomTypeModelSeparatorField } from "./types/model/separator";
 export type {
 	CustomTypeModelField,
 	CustomTypeModelFieldForGroup,
+	CustomTypeModelFieldForNestedGroup,
 	CustomTypeModelFieldForSlicePrimary,
 } from "./types/model/types";
 

src/types/model/group.ts

@@ -1,5 +1,6 @@
 import type {
 	CustomTypeModelFieldForGroup,
+	CustomTypeModelFieldForNestedGroup,
 	CustomTypeModelFieldType,
 } from "./types";
 
@@ -22,3 +23,17 @@ export interface CustomTypeModelGroupField<
 		fields?: Fields;
 	};
 }
+
+/**
+ * A nested group custom type field.
+ *
+ * More details: {@link https://prismic.io/docs/group}
+ *
+ * @typeParam Fields - A record of fields that can be repeated.
+ */
+export type CustomTypeModelNestedGroupField<
+	Fields extends Record<string, CustomTypeModelFieldForNestedGroup> = Record<
+		string,
+		CustomTypeModelFieldForNestedGroup
+	>,
+> = CustomTypeModelGroupField<Fields>;

src/types/model/sharedSliceVariation.ts

@@ -1,5 +1,5 @@
 import type {
-	CustomTypeModelFieldForGroup,
+	CustomTypeModelFieldForNestedGroup,
 	CustomTypeModelFieldForSlicePrimary,
 } from "./types";
 
@@ -17,10 +17,10 @@ export interface SharedSliceModelVariation<
 		string,
 		CustomTypeModelFieldForSlicePrimary
 	> = Record<string, CustomTypeModelFieldForSlicePrimary>,
-	ItemFields extends Record<string, CustomTypeModelFieldForGroup> = Record<
+	ItemFields extends Record<
 		string,
-		CustomTypeModelFieldForGroup
-	>,
+		CustomTypeModelFieldForNestedGroup
+	> = Record<string, CustomTypeModelFieldForNestedGroup>,
 > {
 	id: ID;
 	name: string;

src/types/model/slice.ts

@@ -1,6 +1,6 @@
-import type { CustomTypeModelFieldForGroup } from "./types";
+import type { CustomTypeModelFieldForNestedGroup } from "./types";
 
-import type { CustomTypeModelGroupField } from "./group";
+import type { CustomTypeModelNestedGroupField } from "./group";
 import type { CustomTypeModelSliceType } from "./sliceZone";
 
 /**
@@ -12,14 +12,14 @@ import type { CustomTypeModelSliceType } from "./sliceZone";
  * @typeParam RepeatFields - A record of fields that can be repeated.
  */
 export interface CustomTypeModelSlice<
-	NonRepeatFields extends Record<string, CustomTypeModelFieldForGroup> = Record<
+	NonRepeatFields extends Record<
 		string,
-		CustomTypeModelFieldForGroup
-	>,
-	RepeatFields extends Record<string, CustomTypeModelFieldForGroup> = Record<
+		CustomTypeModelFieldForNestedGroup
+	> = Record<string, CustomTypeModelFieldForNestedGroup>,
+	RepeatFields extends Record<
 		string,
-		CustomTypeModelFieldForGroup
-	>,
+		CustomTypeModelFieldForNestedGroup
+	> = Record<string, CustomTypeModelFieldForNestedGroup>,
 > {
 	type: typeof CustomTypeModelSliceType.Slice;
 	fieldset?: string | null;
@@ -46,5 +46,5 @@ export const CustomTypeModelSliceDisplay = {
  * @deprecated - Legacy slice type. Do not use.
  */
 export type CustomTypeModelLegacySlice =
-	| CustomTypeModelGroupField
-	| CustomTypeModelFieldForGroup;
+	| CustomTypeModelNestedGroupField
+	| CustomTypeModelFieldForNestedGroup;

src/types/model/types.ts

@@ -4,7 +4,10 @@ import type { CustomTypeModelContentRelationshipField } from "./contentRelations
 import type { CustomTypeModelDateField } from "./date";
 import type { CustomTypeModelEmbedField } from "./embed";
 import type { CustomTypeModelGeoPointField } from "./geoPoint";
-import type { CustomTypeModelGroupField } from "./group";
+import type {
+	CustomTypeModelGroupField,
+	CustomTypeModelNestedGroupField,
+} from "./group";
 import type { CustomTypeModelImageField } from "./image";
 import type { CustomTypeModelIntegrationField } from "./integration";
 import type { CustomTypeModelKeyTextField } from "./keyText";
@@ -65,19 +68,26 @@ export type CustomTypeModelField =
 	| CustomTypeModelUIDField
 	| CustomTypeModelGroupField
 	| CustomTypeModelSliceZoneField
-	| CustomTypeModelFieldForGroup;
+	| CustomTypeModelFieldForNestedGroup;
 
 /**
  * Any custom type field that is valid for a slice's primary section.
  */
 export type CustomTypeModelFieldForSlicePrimary =
 	| CustomTypeModelGroupField
-	| CustomTypeModelFieldForGroup;
+	| CustomTypeModelFieldForNestedGroup;
 
 /**
  * Any custom type field that is valid for a group field.
  */
 export type CustomTypeModelFieldForGroup =
+	| CustomTypeModelNestedGroupField
+	| CustomTypeModelFieldForNestedGroup;
+
+/**
+ * Any custom type field that is valid for a nested group field.
+ */
+export type CustomTypeModelFieldForNestedGroup =
 	| CustomTypeModelBooleanField
 	| CustomTypeModelColorField
 	| CustomTypeModelDateField

src/types/value/group.ts

@@ -6,9 +6,22 @@ import type { AnyRegularField, FieldState } from "./types";
  * More details: {@link https://prismic.io/docs/group}
  */
 export type GroupField<
+	Fields extends Record<string, AnyRegularField | NestedGroupField> = Record<
+		string,
+		AnyRegularField | NestedGroupField
+	>,
+	State extends FieldState = FieldState,
+> = State extends "empty" ? [] : [Fields, ...Fields[]];
+
+/**
+ * A nested group field.
+ *
+ * More details: {@link https://prismic.io/docs/group}
+ */
+export type NestedGroupField<
 	Fields extends Record<string, AnyRegularField> = Record<
 		string,
 		AnyRegularField
 	>,
 	State extends FieldState = FieldState,
-> = State extends "empty" ? [] : [Fields, ...Fields[]];
+> = GroupField<Fields, State>;

test/types/customType-group.types.ts

@@ -77,6 +77,38 @@ expectType<
 	},
 });
 
+/**
+ * Supports nested groups.
+ */
+expectType<
+	prismic.CustomTypeModelGroupField<{
+		foo: prismic.CustomTypeModelNestedGroupField<{
+			bar: prismic.CustomTypeModelBooleanField;
+		}>;
+	}>
+>({
+	type: prismic.CustomTypeModelFieldType.Group,
+	config: {
+		label: "string",
+		fields: {
+			foo: {
+				type: prismic.CustomTypeModelFieldType.Group,
+				config: {
+					label: "string",
+					fields: {
+						bar: {
+							type: prismic.CustomTypeModelFieldType.Boolean,
+							config: {
+								label: "string",
+							},
+						},
+					},
+				},
+			},
+		},
+	},
+});
+
 /**
  * `@prismicio/types` extends `@prismicio/types-internal`
  */

test/types/customType.types.ts

@@ -255,6 +255,12 @@ expectType<
 		prismic.CustomTypeModelLinkToMediaField
 	>
 >(true);
+expectType<
+	TypeOf<
+		prismic.CustomTypeModelFieldForGroup,
+		prismic.CustomTypeModelNestedGroupField
+	>
+>(true);
 expectType<
 	TypeOf<
 		prismic.CustomTypeModelFieldForGroup,

test/types/fields-group.types.ts

@@ -58,15 +58,14 @@ expectType<prismic.GroupField<{ boolean: prismic.BooleanField }>>([
 	},
 ]);
 
+/**
+ * Supports nested groups.
+ */
+expectType<prismic.GroupField<{ group: prismic.NestedGroupField }>>([]);
+
 /**
  * Custom fields may only contain group-compatible fields.
  */
-expectType<
-	prismic.GroupField<// @ts-expect-error - Groups are invalid within group fields.
-	{
-		group: prismic.GroupField;
-	}>
->([]);
 expectType<
 	prismic.GroupField<// @ts-expect-error - Slice Zones are invalid within group fields.
 	{

test/types/fields.types.ts

@@ -19,7 +19,7 @@ import * as prismic from "../../src";
 };
 
 /**
- * AnyRegularField supports any field compatible with a Group.
+ * AnyRegularField supports any field compatible with a nested Group.
  */
 expectType<TypeOf<prismic.AnyRegularField, prismic.BooleanField>>(true);
 expectType<TypeOf<prismic.AnyRegularField, prismic.ColorField>>(true);
@@ -41,10 +41,11 @@ expectType<TypeOf<prismic.AnyRegularField, prismic.TimestampField>>(true);
 expectType<TypeOf<prismic.AnyRegularField, prismic.TitleField>>(true);
 
 /**
- * AnyRegularField excludes any fields not compatible with a Group.
+ * AnyRegularField excludes any fields not compatible with a nested Group.
  */
 expectType<TypeOf<prismic.AnyRegularField, prismic.SliceZone>>(false);
 expectType<TypeOf<prismic.AnyRegularField, prismic.GroupField>>(false);
+expectType<TypeOf<prismic.AnyRegularField, prismic.NestedGroupField>>(false);
 
 /**
  * AnySlicePrimaryField supports any field compatible with a slice's primary

test/types/helpers-isFilled.types.ts

@@ -517,7 +517,10 @@ type IntegrationFieldData = { foo: string };
  * Group
  */
 
-type GroupDefault = Record<string, prismic.AnyRegularField>;
+type GroupDefault = Record<
+	string,
+	prismic.AnyRegularField | prismic.NestedGroupField
+>;
 
 // Default
 (value: prismic.GroupField) => {