bacnet-js / client / 23839569494

85%

Build Type

push

github

Committed by web-flow

Commit Message

fix: decode special log records in ReadRange without status flags (#77)

Fixes ReadRange decoding when TREND_LOG contains special log records
(e.g., `log-interrupted`, `time-change`) that don't have status flags.

## Problem

When reading a `TREND_LOG` that contains a special log record, records
after it were silently missing from the result. The issue was that
`decodeRange` unconditionally consumed the status flags bytes after the
log-datum value, but special records don't have status flags. This
caused the decoder to read into the bytes of the next record and lose
sync.

## Solution

Updated `decodeRange` in `src/lib/asn1.ts` to:
- Validate closing tag 1 before consuming it
- Check for context tag 2 presence before decoding status flags (status
flags are **optional for ALL record types** per ASHRAE 135 §12.25)
- Add support for log-status choice (context tag 0 - special records
like `log-disabled`, `buffer-purged`, `log-interrupted`)
- Add support for time-change choice (context tag 9 - clock adjustment
records)
- Add `isLogStatus`, `logStatus`, and `isTimeChange` fields to
differentiate special records

## Type Changes

- Extracted `LogRecord`, `LogStatusFlags`, `LogRecordStatusFlags`
interfaces to `types.ts`
- Updated `ReadRangeAcknowledge.values` to use `LogRecord[]` instead of
`any[]`
- Added `LogRecordValue` union type to narrow `LogRecord.value`
- Added ASHRAE 135 §12.25 standard references to code comments

## Testing

- Added unit test for special log-status records without status flags
(mixed with normal records)
- Added unit test for time-change records without status flags
- All 204 unit tests pass
- Linting passes
- Build passes
- CodeQL security scan - no issues found

<!-- START COPILOT ORIGINAL PROMPT -->



<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>ReadRange bug when response contains a special log
record</issue_title>
> <issue_descr... (continued)

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