[PerryLink]

Problem

test runs yakumo test --import tsx, but the loader never reaches the node --test child process. yakumo's CLI splices every --import <path> argument out of process.argv and imports it into its own process; the test command then spawns node --test with only the options that are still present. The child therefore gets no TypeScript loader and dies on the first .ts file:

code: 'ERR_UNSUPPORTED_DIR_IMPORT'
url: 'file:///.../packages/element/src'
✖ packages/element/tests/segment.spec.ts

This is exactly the failure visible on the current v4 head in CI: test (20) and test (22) both end with ERR_UNKNOWN_FILE_EXTENSION before any test runs.

Fix

Put the loader in NODE_OPTIONS, which the spawned node --test inherits:

-    "test": "yakumo test --import tsx",
+    "test": "NODE_OPTIONS=\"--import tsx\" yakumo test",

One line. POSIX shell syntax is fine here — CI runs on ubuntu-latest, and the existing scripts already rely on a POSIX shell.

Relation to #433

#433 carries the same change against main. main is no longer where development happens: its install has been broken since 2026-10-07 on an unpublished dependency, and active work moved to v4. This PR is the v4 version of that fix; #433 is superseded by it.

Verification (local, Node 24.22.1)

Before, with the old script:

$ pnpm test element/segment
code: 'ERR_UNSUPPORTED_DIR_IMPORT',
url: 'file:///tmp/wk-satori/satori/packages/element/src'
✖ packages/element/tests/segment.spec.ts
ℹ pass 0
ℹ fail 1

After:

$ pnpm test element/segment
ℹ tests 13
ℹ pass 13
ℹ fail 0

Also:

• pnpm exec yakumo build element — exit 0 (lib/index.cjs, lib/index.mjs, lib/index.d.ts emitted)
• pnpm lint — exit 0 (no output)

CI

On v4's head the test job was red for this reason — it died at load time, not on an assertion (run 40496672330). With this PR all relevant checks pass (40895466269):

• test (20) — success
• test (22) — success (13 tests, 13 pass, 0 fail; @satorijs/element and @satorijs/protocol both load)
• lint — success
• build — success
• publish — skipped on pull requests

For completeness: the publish job is red on the v4 head run, but that is a pre-existing failure unrelated to this one-line script change. The test job's red state was not an unrelated pre-existing assertion failure — it was this loader bug, and it is fixed here.

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Additional details and impacted files

@@          Coverage Diff          @@
##             v4     #438   +/-   ##
=====================================
  Coverage      ?   92.53%           
=====================================
  Files         ?        2           
  Lines         ?     1072           
  Branches      ?      132           
=====================================
  Hits          ?      992           
  Misses        ?       80           
  Partials      ?        0           

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