# discarded-shielded-send-result

> Canonical shielded send or mint metadata is discarded or retained only by unused immutable aliases.

Canonical: https://nightshade.dicksonwu.xyz/rules/discarded-shielded-send-result.html
Release: Nightshade 0.1.1 (v0.1.1)

| Field | Value |
| --- | --- |
| Rule ID | `discarded-shielded-send-result` |
| Severity | info |
| Confidence | varies |
| Maturity | experimental |
| Selection | Audit default |
| Policy intent | not required |
| Default enabled | yes |
| Category | Audit-default ordinary rules |
| Engine facts used | resolved-source-references, typed-source-constants |
| Release | v0.1.1 |

## Selection and scope

Selected by the default audit profile, so an ordinary scan runs it.

```sh
./.nightshade/node_modules/.bin/nightshade ./contracts --detectors discarded-shielded-send-result
./.nightshade/node_modules/.bin/nightshade detector show discarded-shielded-send-result
```

The first command runs only this rule; `--detectors` takes a comma-separated list. The second prints the rule's metadata from your installed version.

Severity is review priority. It does not express exploitability or impact. Confidence is detector metadata, not a probability. All built-in rules are experimental.

Compiler scope: the engine supports the pinned profiles 0.28.0, 0.29.0, 0.30.0, 0.31.1, 0.33.0-rc.2, 0.34.0, 0.35.0-rc.1 and 0.35.0, with ZKIR2 by default. Support for this rule can be narrower; the rule documentation below states any narrower scope.

## Corpus checks

Synthetic corpus checks for this rule in the 0.1.1 proof run. A check counts only with compiler acceptance and complete analysis.

| Positive detected | Corrected quiet | Lookalike quiet | Other negative quiet | Incomplete |
| ---: | ---: | ---: | ---: | ---: |
| 5/5 | 5/5 | 5/5 | 0/0 | 0 |

No deviations were recorded for this rule.

These are behavior checks on synthetic fixtures, not a precision or recall estimate. See [evaluation](https://nightshade.dicksonwu.xyz/evaluation.md#synthetic-corpus).

## Rule documentation

From https://github.com/DicksonWu654/nightshade/blob/v0.1.1/docs/detectors/discarded-shielded-send-result.md at v0.1.1.

Availability: **default**; informational severity, high confidence in the source
observation. No policy required.

Informational source-use review; no policy required. Select it alone with
`--detectors discarded-shielded-send-result`.

The rule observes discarded results from canonical stdlib `sendImmediateShielded`
and `sendShielded`, and coin descriptors from `mintShieldedToken`, in structurally
reachable root-source circuits. It recognizes
expression statements (including transparent disclosure/identity casts) and unused
immutable local identity alias chains. Imported aliases keep canonical identity;
custom same-name helpers do not match. A helper consisting only of an exact
return of a producer or another transparent helper also qualifies. Helpers with
setup, branches, partial field returns or computed returns remain outside.
Any non-alias reference, including field
selection, assignment, capture or return, conservatively retains the result.

The returned `ShieldedSendResult` contains `sent: ShieldedCoinInfo` and
`change: Maybe<ShieldedCoinInfo>`. Review whether the application needs that
metadata. Discard does not establish lost funds, spendability or exploitation:
wallet or transaction machinery may independently retain metadata. A use of one
field silences the rule without proving all metadata is handled correctly.
Returning the original input coin does not retain a discarded output descriptor.

This bounded source pass has a separate mode/cache and preserves ordinary,
validation and comparison allowances. It shares existing constant-source reach,
short-circuit and definite-rejection handling. Sequence-prefix discard, arbitrary
forwarding helpers, recipient policy and off-chain retention are outside scope.
Callback reach is structural and does not prove execution or nonzero iterations.
Exhaustion yields an incomplete-rule diagnostic and no findings. Main and Counter
scans route this rule through source-only analysis; no engine transfer changes.

## Suppress a match

If a match is intentional, suppress it on the line before with the exact rule ID and a reason of at least eight characters:

```compact
// nightshade-disable-next-line discarded-shielded-send-result -- Reason this match is intentional
```

Diagnostics cannot be suppressed, and an unmatched directive for a selected rule makes analysis incomplete. See [configuration](https://nightshade.dicksonwu.xyz/configuration.md#suppress-an-intentional-match) for fingerprint suppressions and baselines.

## References

- [Rule source document at v0.1.1](https://github.com/DicksonWu654/nightshade/blob/v0.1.1/docs/detectors/discarded-shielded-send-result.md)
- [Catalog entry in rules.json](https://nightshade.dicksonwu.xyz/rules.json)
- [All rules](https://nightshade.dicksonwu.xyz/rules.md#audit-default-ordinary-rules)
- [Limitations](https://nightshade.dicksonwu.xyz/limitations.md)