fix inference on constrained index signature (#986)

.changeset/quiet-hairs-tap.md

@@ -0,0 +1,3 @@
+---
+"@arktype/schema": patch
+---

ark/schema/ast.ts

@@ -21,9 +21,9 @@ export type Constraints = {
 	literal?: string | number
 }
 
-declare const constrained: unique symbol
+export declare const constrained: unique symbol
 
-type constrained = typeof constrained
+export type constrained = typeof constrained
 
 export type of<base, constraints extends Constraints> = [
 	base,

ark/schema/keywords/validation.ts

@@ -56,6 +56,7 @@ const creditCard = root.defineRoot({
 export interface validationExports {
 	alpha: string
 	alphanumeric: string
+	digits: string
 	lowercase: string
 	uppercase: string
 	creditCard: string
@@ -72,7 +73,8 @@ export type validation = SchemaModule<validationExports>
 export const validation: validation = schemaScope(
 	{
 		alpha: defineRegex(/^[A-Za-z]*$/, "only letters"),
-		alphanumeric: defineRegex(/^[A-Za-z\d]*$/, "only letters and digits"),
+		alphanumeric: defineRegex(/^[A-Za-z\d]*$/, "only letters and digits 0-9"),
+		digits: defineRegex(/^\d*$/, "only digits 0-9"),
 		lowercase: defineRegex(/^[a-z]*$/, "only lowercase letters"),
 		uppercase: defineRegex(/^[A-Z]*$/, "only uppercase letters"),
 		creditCard,

ark/type/CHANGELOG.md

@@ -1,5 +1,22 @@
 # arktype
 
+## 2.0.0-dev.18
+
+Add a `"digits"` keyword for strings consisting exclusively of 0-9.
+
+Fix an issue causing index signatures with constraints like regex to be considered invalid as definitions.
+
+The following is valid and now will be allowed as a definition.
+
+```ts
+const test = scope({
+	svgPath: /^\.\/(\d|a|b|c|d|e|f)+(-(\d|a|b|c|d|e|f)+)*\.svg$/,
+	svgMap: {
+		"[svgPath]": "digits"
+	}
+}).export()
+```
+
 ## 2.0.0-dev.17
 
 - Error thrown by `.assert` or `out.throw()` is now an instance of [AggregateError](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError), with the cause being an `ArkErrors` array.

ark/type/__tests__/expressions.test.ts

@@ -45,6 +45,7 @@ contextualize(
 					"url",
 					"alpha",
 					"alphanumeric",
+					"digits",
 					"lowercase",
 					"uppercase",
 					"creditCard",
@@ -94,6 +95,7 @@ contextualize(
 					"url",
 					"alpha",
 					"alphanumeric",
+					"digits",
 					"lowercase",
 					"uppercase",
 					"creditCard",

ark/type/__tests__/keywords.test.ts

@@ -102,7 +102,14 @@ contextualize(
 			attest(alphanumeric("user")).snap("user")
 			attest(alphanumeric("123")).snap("123")
 			attest(alphanumeric("abc@123").toString()).equals(
-				'must be only letters and digits (was "abc@123")'
+				'must be only letters and digits 0-9 (was "abc@123")'
+			)
+		})
+		it("digits", () => {
+			const digits = type("digits")
+			attest(digits("123")).snap("123")
+			attest(digits("user123").toString()).equals(
+				'must be only digits 0-9 (was "user123")'
 			)
 		})
 		it("lowercase", () => {

ark/type/__tests__/realWorld.test.ts

@@ -2,6 +2,7 @@ import { attest, contextualize } from "@arktype/attest"
 import type { AtLeastLength, AtMostLength, Out, string } from "@arktype/schema"
 import { registeredReference } from "@arktype/util"
 import { scope, type, type Type } from "arktype"
+import type { Module } from "../module.js"
 
 contextualize(() => {
 	// https://github.com/arktypeio/arktype/issues/915
@@ -430,16 +431,28 @@ nospace must be matched by ^\\S*$ (was "One space")`)
 
 		attest(out).snap([{ token: "lovelace", amount: "5000000n" }])
 	})
-	it("union with domain and proto", () => {
-		const t = type("RegExp | string")
-		attest(t.raw.assertHasKind("union").discriminantJson).snap({
-			kind: "domain",
-			path: [],
-			cases: { '"string"': true, '"object"': { proto: "RegExp" } }
+
+	it("regex index signature", () => {
+		const test = scope({
+			svgPath: /^\.\/(\d|a|b|c|d|e|f)+(-(\d|a|b|c|d|e|f)+)*\.svg$/,
+			svgMap: {
+				"[svgPath]": "digits"
+			}
+		}).export()
+		attest<
+			Module<{
+				svgMap: {
+					[x: string & string.matching<string>]: string
+				}
+				svgPath: string.matching<string>
+			}>
+		>(test)
+		attest(test.svgMap({ "./f.svg": "123", bar: 5 })).unknown.snap({
+			"./f.svg": "123",
+			bar: 5
 		})
-		attest(t.allows("es")).equals(true)
-		attest(t.allows(5)).equals(false)
-		attest(t("es")).equals("es")
-		attest(t(new Date()).toString()).snap("must be a RegExp (was Date)")
+		attest(test.svgMap({ "./f.svg": "123a" }).toString()).snap(
+			'value at ["./f.svg"] must be only digits 0-9 (was "123a")'
+		)
 	})
 })

ark/type/package.json

@@ -1,7 +1,7 @@
 {
 	"name": "arktype",
 	"description": "TypeScript's 1:1 validator, optimized from editor to runtime",
-	"version": "2.0.0-dev.17",
+	"version": "2.0.0-dev.18",
 	"license": "MIT",
 	"author": {
 		"name": "David Blass",

ark/type/parser/objectLiteral.ts

@@ -5,6 +5,7 @@ import {
 	type Default,
 	type MutableInner,
 	type NodeSchema,
+	type of,
 	type PropKind,
 	type StructureNode,
 	type UndeclaredKeyBehavior,
@@ -17,10 +18,10 @@ import {
 	stringAndSymbolicEntriesOf,
 	throwParseError,
 	unset,
+	type anyOrNever,
 	type Dict,
 	type ErrorMessage,
 	type Key,
-	type anyOrNever,
 	type keyError,
 	type merge,
 	type mutable,
@@ -150,7 +151,9 @@ export type validateObjectLiteral<def, $, args> = {
 		validateString<indexDef, $, args> extends ErrorMessage<infer message> ?
 			// add a nominal type here to avoid allowing the error message as input
 			keyError<message>
-		: inferDefinition<indexDef, $, args> extends PropertyKey ?
+		: inferDefinition<indexDef, $, args> extends (
+			PropertyKey | of<PropertyKey, {}>
+		) ?
 			// if the indexDef is syntactically and semantically valid,
 			// move on to the validating the value definition
 			validateDefinition<def[k], $, args>
@@ -177,7 +180,10 @@ type validatePossibleDefaultValue<def, k extends keyof def, $, args> =
 type nonOptionalKeyFrom<k, $, args> =
 	parseKey<k> extends PreparsedKey<"required", infer inner> ? inner
 	: parseKey<k> extends PreparsedKey<"index", infer inner> ?
-		inferDefinition<inner, $, args> & Key
+		inferDefinition<inner, $, args> extends infer t ?
+			// symbols are not constrainable
+			(t extends of<any, any> ? string : Key) & t
+		:	never
 	:	// "..." is handled at the type root so is handled neither here nor in optionalKeyFrom
 		// "+" has no effect on inference
 		never