Replace hardcoded value in precompileMorphs for tuple defaults (#1574)

* expose hardcoded default value in precompileMorphs (introduced in #1381)

* fix hardcoded default value in `precompuledMorphs`

Author: shaungrady

ark/schema/structure/structure.ts

@@ -1026,7 +1026,8 @@ const precompileMorphs = (js: NodeCompiler, node: Structure.Node) => {
 		if (node.sequence?.defaultables) {
 			js.for(
 				`i < ${node.sequence.defaultables.length}`,
-				js => js.set(`data[i]`, 5),
+				js =>
+					js.line(`${node.sequence!.defaultValueMorphsReference}[i]${args}`),
 				`data.length - ${node.sequence.prefixLength}`
 			)
 		}

ark/type/__tests__/arrays/defaults.test.ts

@@ -1,4 +1,5 @@
 import { attest, contextualize } from "@ark/attest"
+import { Traversal } from "@ark/schema"
 import { type } from "arktype"
 import { defaultablePostOptionalMessage } from "arktype/internal/parser/tupleLiteral.ts"
 
@@ -108,4 +109,18 @@ contextualize(() => {
 
 		attest(T.out.expression).snap("[number]")
 	})
+
+	it("compiled defaults use correct values", () => {
+		const T = type(["string = 'foo'"])
+		const internal = T.internal
+
+		// Call traverseApply directly with a Traversal context
+		// This exercises the JIT-compiled code path
+		const data: string[] = []
+		const ctx = new Traversal(data, internal.$.resolvedConfig)
+		internal.traverseApply(data, ctx)
+		const result = ctx.finalize(null)
+
+		attest(result).equals(["foo"])
+	})
 })