Allow symbols in Brand (#180)

.changeset/rich-impalas-brake.md

@@ -0,0 +1,5 @@
+---
+"@effect/schema": minor
+---
+
+Allow symbols in Brand

docs/modules/Schema.ts.md

@@ -341,7 +341,7 @@ Schema<A> + B -> Schema<A & Brand<B>>
 **Signature**
 
 ```ts
-export declare const brand: <B extends string, A>(
+export declare const brand: <B extends string | symbol, A>(
   brand: B,
   options?: AnnotationOptions<A> | undefined
 ) => <I>(self: Schema<I, A>) => BrandSchema<I, any>

dtslint/ts4.7/Brand.errors.ts

@@ -0,0 +1,19 @@
+import * as S from "@effect/schema/Schema";
+import { pipe } from "@effect/data/Function";
+
+const Int1 = Symbol.for('Int')
+const Int2 = Symbol.for('Int')
+
+const schema1 = pipe(S.number, S.int(), S.brand(Int1))
+const schema2 = pipe(S.number, S.int(), S.brand(Int2))
+
+type A1 = S.To<typeof schema1>
+type A2 = S.To<typeof schema2>
+
+declare const a1: A1
+declare const a2: A2
+declare const f: (int: A1) => void
+
+f(a1)
+// $ExpectError
+f(a2)

package.json

@@ -106,8 +106,8 @@
     "zod": "^3.21.4"
   },
   "dependencies": {
-    "@effect/data": "~0.5.0",
-    "@effect/io": "^0.10.0",
+    "@effect/data": "^0.6.0",
+    "@effect/io": "^0.12.2",
     "fast-check": "^3.7.1"
   },
   "pnpm": {

src/Schema.ts

@@ -570,7 +570,7 @@ export interface BrandSchema<From, To extends Brand<any>>
  * @category combinators
  * @since 1.0.0
  */
-export const brand = <B extends string, A>(
+export const brand = <B extends string | symbol, A>(
   brand: B,
   options?: AnnotationOptions<A>
 ) =>
@@ -1217,7 +1217,7 @@ export const BrandTypeId = "@effect/schema/BrandTypeId"
  * @category combinators
  * @since 1.0.0
  */
-export const fromBrand = <C extends Brand<string>>(
+export const fromBrand = <C extends Brand<string | symbol>>(
   constructor: Brand.Constructor<C>,
   options?: AnnotationOptions<Brand.Unbranded<C>>
 ) =>

test/Decoder.ts

@@ -363,6 +363,17 @@ describe.concurrent("Decoder", () => {
     )
   })
 
+  it("brand/symbol decoding", async () => {
+    const Int = Symbol.for("Int")
+    const schema = pipe(S.string, S.numberFromString, S.int(), S.brand(Int))
+    await Util.expectParseSuccess(schema, "1", 1 as any)
+    await Util.expectParseFailure(
+      schema,
+      null,
+      `Expected string, actual null`
+    )
+  })
+
   it("tuple. empty", async () => {
     const schema = S.tuple()
     await Util.expectParseSuccess(schema, [])

test/Schema.ts

@@ -77,6 +77,26 @@ describe.concurrent("Schema", () => {
     })
   })
 
+  it("brand/symbol annotations", () => {
+    const A = Symbol.for("A")
+    const B = Symbol.for("B")
+    const Branded = pipe(
+      S.string,
+      S.numberFromString,
+      S.int(),
+      S.brand(A),
+      S.brand(B, {
+        description: "a B brand"
+      })
+    )
+    expect(Branded.ast.annotations).toEqual({
+      [AST.TypeAnnotationId]: "@effect/schema/IntTypeId",
+      [AST.BrandAnnotationId]: [A, B],
+      [AST.DescriptionAnnotationId]: "a B brand",
+      [AST.JSONSchemaAnnotationId]: { type: "integer" }
+    })
+  })
+
   it("brand/ ()", () => {
     const Int = pipe(S.string, S.numberFromString, S.int(), S.brand("Int"))
     expect(Int(1)).toEqual(1)