vitest-5-0-0-9-b

Question

Which folder does vitest --merge-reports read from by default?

Answer key

A correct answer says

The blob reporter and --merge-reports use .vitest/blob/ by default.

The stale answer

Blob reports go to .vitest-reports/ by default.

The change's lesson

Answer

In the vitest version installed here (5.0.3), `vitest --merge-reports` reads from `.vitest/blob/` by default. The blob reporter writes there by default too. I checked this in the installed package: `node_modules/vitest/dist/chunks/cac.DfDGTQ9W.js` falls back to `".vitest/blob"` when you don't give a path, and the type definitions list `.vitest/blob` as the default. Older vitest versions (before 5.0) used `.vitest-reports` instead, so older scripts or CI steps that point at that folder need updating. To read from somewhere else, pass the path explicitly, e.g. `vitest --merge-reports=path/to/blobs`.

Answering cost $0.08.

Grade

correct

The judge's reason: It states that `.vitest/blob/` is the current default and mentions `.vitest-reports` only as older behavior.

The judge's log

Session log

What the agent wrote, the tools it called, and what they returned, from docs/bench/2026-10-11-done3/runs/B-project-sync/vitest-5-0-0-9-b.jsonl. Thinking and the session's settings are left out. The raw log

1. Tool call: Grep

   {
     "pattern": "\\.vitest[-/](reports|blob)",
     "path": "C:\\Users\\haya0\\AppData\\Local\\Temp\\ludion-bench-GEGgwK\\work",
     "output_mode": "content",
     "head_limit": 10
   }

2. Tool output

   .ludion\lessons.md:9:- vitest >=5.0.0 changed the default of `--merge-reports`. By default, Vitest stores all blob test results in .vitest/blob/, so they can be later merged using --merge-reports. Silent: code written for older versions still runs, without an error. (installed: vitest 5.0.3)
   node_modules\vitest\dist\chunks\cac.DfDGTQ9W.js:1216:			if (!value || typeof value === "boolean") return ".vitest/blob";
   node_modules\vitest\dist\chunks\plugin.d.BsjqSb4-.d.ts:4337:	* @default '.vitest/blob'

3. Agent

   In the vitest version installed here (5.0.3), `vitest --merge-reports` reads from `.vitest/blob/` by default. The blob reporter writes there by default too. I checked this in the installed package: `node_modules/vitest/dist/chunks/cac.DfDGTQ9W.js` falls back to `".vitest/blob"` when you don't give a path, and the type definitions list `.vitest/blob` as the default. Older vitest versions (before 5.0) used `.vitest-reports` instead, so older scripts or CI steps that point at that folder need updating. To read from somewhere else, pass the path explicitly, e.g. `vitest --merge-reports=path/to/blobs`.