[Kshot3000]

Summary

Fixes #481: CIP-30 signData returns a DataSignature of { signature, key }, where key is the CBOR-encoded COSE_Key needed to verify the signature. SignData.signData produces both, but the wallet's signMessage returned only { payload, signature } and dropped the key, and the wallet SignedMessage interface had no key field — so a consumer could not verify a message signed via the wallet API without obtaining the public key some other way.

Fix

• packages/evolution/src/sdk/wallet/Wallet.ts — SignedMessage gains a key field (hex-encoded COSE_Key), with the doc comment stating the CIP-30 DataSignature shape.
• packages/evolution/src/sdk/client/internal/Signing.ts — the seed/private-key wallet's signMessage returns key: Bytes.toHex(signed.key) alongside the signature; the key was already computed by SignData.signData, it was just discarded.
• packages/evolution/src/sdk/client/internal/Wallets.ts — the CIP-30 api wallet's signMessage carries the extension's result.key through, so both wallet types return a complete DataSignature.

Tests

New file packages/evolution/test/SignMessage.DataSignature.test.ts (4 tests), each verified failing on main first:

• seed wallet: result.key is undefined on main (expected 'undefined' to be 'string'); after the fix it is a non-empty hex string that decodes as CBOR.
• seed wallet: SignData.verifyData verifies using only the returned { signature, key } (plus the address and the signer's key hash) — self-contained CIP-30 verification, exactly what was impossible before.
• seed wallet: the returned key and signature match what SignData.signData produces for the signing key.
• CIP-30 api wallet: a stub extension returning { signature: "deadbeef", key: "cafebabe" } — on main the key is dropped; after the fix signMessage returns it unchanged.

Full suite: 1682 passed / 75 skipped / 0 failed, test files 102 passed / 1 skipped of 103 — exactly main's 1678 baseline + the 4 new tests. tsc --noEmit clean, eslint clean, and the three touched source files carry exactly the same prettier diff-line counts as unmodified main (5 / 10 / 320 — they fail prettier on main too; no new formatting drift). A patch changeset is included.

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Independent builder — not affiliated with the Cardano Foundation, IOG or Intersect.

@Kshot9000 (https://x.com/kshot9000) · ADA donations: addr1q8hnl6vl5a6k3rw3n5g3jtte696zcl76kfatzv7gpswa9r0dj7fma6klq55y4ffm7tf0em09udnyhuk4ah92pl5x9jpqjae44v

cc @cardano-foundation @IntersectMBO

[emmanuel-musau]

Closing: we're not accepting bulk
automated contributions. The linked issues stay open.