enbility / eebus-go / 27195019205

95%

Build Type

push

github

Committed by web-flow

Commit Message

Add missing nil/length guards before pointer dereferences (#219)

Follow-up to #218.

While fixing #217, I audited the codebase for the same class of bug — a
slice element subfield dereferenced without a nil guard, or `[0]`
indexing without a `len > 0` check. EEBus model fields are almost all
`*T` and optional per spec, so a conformant remote that omits one of
them would panic the client.

## Findings

| File | Site | Pattern |
| --- | --- | --- |
| `usecases/cem/evcem/public.go` | `PowerPerPhase` |
`*elParam[0].AcMeasuredPhases` dereferenced; only `len(elParam) == 0`
was guarded. `AcMeasuredPhases` is optional. |
| `usecases/cem/cevc/public_scen3.go` |
`WriteIncentiveTableDescriptions` | `descriptions[0].TariffDescription`
accessed after only an error check; no `len(descriptions) > 0` guard. |
| `usecases/eg/lpc/public.go` | `ConsumptionLimit` |
`*limitDescriptions[0].LimitId` dereferenced; `len(limitDescriptions) !=
1` was guarded but `LimitId == nil` was not. |
| `usecases/eg/lpp/public.go` | `ProductionLimit` | Same pattern as
`lpc/public.go`. |

Each site adds the missing guard and bails out early (`continue` / early
return / `api.ErrDataNotAvailable`).

## Test

No fixture changes — these are defensive guards against malformed remote
data and the existing per-usecase test suites continue to pass:

```
go test ./usecases/cem/evcem/... ./usecases/cem/cevc/... ./usecases/eg/lpc/... ./usecases/eg/lpp/...
ok  github.com/enbility/eebus-go/usecases/cem/evcem
ok  github.com/enbility/eebus-go/usecases/cem/cevc
ok  github.com/enbility/eebus-go/usecases/eg/lpc
ok  github.com/enbility/eebus-go/usecases/eg/lpp
```

Building and vetting the full module is clean.

Coverage Stats

4 of 6 new or added lines in 4 files covered. (66.67%)

13 existing lines in 1 file now uncovered.

7250 of 7612 relevant lines covered (95.24%)

12.41 hits per line