From a1fbd16d8376cb4ab6422b2c7caabecb1726d664 Mon Sep 17 00:00:00 2001
From: Danijel Martinek <danijel@fraqtal.xyz>
Date: Tue, 12 May 2026 21:32:42 +0200
Subject: [PATCH] feat(core-shared/instrumentation): withCapture returns
 Captured<F>

---
 .../src/instrumentation/with-capture.test.ts         | 12 +++++++++++-
 .../core-shared/src/instrumentation/with-capture.ts  |  6 ++++--
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/packages/core-shared/src/instrumentation/with-capture.test.ts b/packages/core-shared/src/instrumentation/with-capture.test.ts
index 8b056d3..28b4803 100644
--- a/packages/core-shared/src/instrumentation/with-capture.test.ts
+++ b/packages/core-shared/src/instrumentation/with-capture.test.ts
@@ -1,7 +1,8 @@
-import { describe, it, expect, vi } from "vitest";
+import { describe, it, expect, expectTypeOf, vi } from "vitest";
 import { withCapture } from "@/instrumentation/with-capture";
 import type { ILogger } from "@/instrumentation/logger.interface";
 import { isReported } from "@/instrumentation/reported-flag";
+import type { Captured } from "@/conformance/brands";
 
 function makeLogger(): ILogger & { captureException: ReturnType<typeof vi.fn> } {
   return {
@@ -60,3 +61,12 @@ describe("withCapture", () => {
     });
   });
 });
+
+describe("withCapture — brand", () => {
+  it("returns a Captured<F>", () => {
+    const logger = makeLogger();
+    const fn = async (a: number) => a + 1;
+    const wrapped = withCapture(logger, { layer: "use-case" }, fn);
+    expectTypeOf(wrapped).toMatchTypeOf<Captured<typeof fn>>();
+  });
+});
diff --git a/packages/core-shared/src/instrumentation/with-capture.ts b/packages/core-shared/src/instrumentation/with-capture.ts
index f9fbeb9..ed17420 100644
--- a/packages/core-shared/src/instrumentation/with-capture.ts
+++ b/packages/core-shared/src/instrumentation/with-capture.ts
@@ -1,4 +1,5 @@
 import type { ILogger } from "./logger.interface";
+import type { Captured } from "../conformance/brands";
 import { isReported, markReported } from "./reported-flag";
 
 /**
@@ -25,8 +26,8 @@ export function withCapture<Args extends unknown[], R>(
   logger: ILogger,
   tags: Record<string, string>,
   fn: (...args: Args) => Promise<R>,
-): (...args: Args) => Promise<R> {
-  return async (...args) => {
+): Captured<(...args: Args) => Promise<R>> {
+  const wrapped: (...args: Args) => Promise<R> = async (...args) => {
     try {
       return await fn(...args);
     } catch (err) {
@@ -37,4 +38,5 @@ export function withCapture<Args extends unknown[], R>(
       throw err;
     }
   };
+  return wrapped as Captured<(...args: Args) => Promise<R>>;
 }