fix(Label_QQ): guard groundspeed on the actual 45..48 field, not remaining.text

[fuleinist]

Fixes #507.

Problem

Label_QQ.decode() guards the groundspeed field by testing decodeResult.remaining.text !== '---', but at that point remaining.text holds the previous unknown field (substring(42, 45)), not the groundspeed field (substring(45, 48)). When 45..48 is --- but 42..45 is not (e.g. ...028---0009), the guard passes and Number('---') stores a NaN groundspeed, rendering "NaN knots".

Fix

Read the groundspeed field into a local (gsField) and include it in the guard:

const gsField = message.text.substring(45, 48);
if (decodeResult.remaining.text !== '---' && gsField !== '---') {
  ResultFormatter.groundspeed(decodeResult, Number(gsField));
} else {
  ResultFormatter.unknown(decodeResult, gsField);
}

Note: I intentionally kept the existing remaining.text check rather than replacing it with a check on gsField alone. The variant 2 fixture (...10.1---0200009) asserts that when the 42..45 field is ---, the following 020 is recorded as unknown rather than decoded as a 20-knot groundspeed. Guarding on gsField alone would change that established behavior; this version preserves both existing fixtures while eliminating the NaN path.

Tests

• Added a regression test for the 028--- split: no groundspeed in raw, no GSPD formatted item, field recorded as unknown.
• All existing Label_QQ tests unchanged and passing.
• Full suite: 100 suites, 469 passed, 9 skipped (pre-existing).

Summary by CodeRabbit

• Bug Fixes

  • Improved handling of Label QQ messages with unavailable groundspeed data.
  • Messages now decode successfully while preserving position, route, and remaining fields.
  • Unavailable groundspeed values are omitted instead of being displayed incorrectly.

• Tests

  • Added regression coverage for messages containing unavailable groundspeed fields.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 5867381c-50d8-4064-82f9-c8b2b28bcc28

📥 Commits

Reviewing files that changed from the base of the PR and between c4b61b4 and 1184c10.

📒 Files selected for processing (2)

• lib/plugins/Label_QQ.test.ts
• lib/plugins/Label_QQ.ts

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Walkthrough

Label QQ groundspeed decoding now checks the extracted groundspeed field. A regression test covers a populated preceding field followed by the '---' placeholder and verifies partial decoding without NaN.

Changes

Label QQ groundspeed decoding

Layer / File(s)	Summary
Groundspeed guard and regression coverage lib/plugins/Label_QQ.ts, lib/plugins/Label_QQ.test.ts	The decoder records '---' as unknown instead of converting it to NaN. The regression test verifies position and route parsing, preserved remaining text, undefined groundspeed, and omitted groundspeed formatting.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested reviewers: makrsmark

Poem

A rabbit checked the fields in line,
Found dashed speed, not a number fine.
No NaN hops through the route,
Unknown marks now safely sprout.
Tests watch every gentle sign.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly identifies the groundspeed guard fix in Label_QQ and matches the primary change.
Linked Issues check	✅ Passed	The change reads the actual 45..48 groundspeed field and adds regression coverage for the split-field case in issue #507.
Out of Scope Changes check	✅ Passed	The changes are limited to the Label_QQ decoder and its regression test, both directly related to issue #507.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

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[Copilot]

🟢 Ready to approve

The fix addresses the documented NaN bug and adds a targeted regression test; remaining feedback is a minor test assertion/type-safety cleanup.

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Pull request overview

Fixes Label_QQ.decode() groundspeed decoding so the --- placeholder is detected on the actual groundspeed field (45..48), preventing Number('---') from producing a NaN groundspeed and "NaN knots" output.

Changes:

• Read groundspeed into a local gsField and guard decoding on gsField !== '---' (while preserving the existing remaining.text !== '---' behavior).
• Add a regression test covering the 028--- split case to ensure groundspeed is not decoded and is recorded as unknown.

File summaries

File	Description
lib/plugins/Label_QQ.ts	Fix groundspeed placeholder guarding by checking the 45..48 groundspeed field directly.
lib/plugins/Label_QQ.test.ts	Add regression coverage for the 028--- case (non-placeholder 42..45 followed by placeholder groundspeed).

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 1
• Review effort level: Lite

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