Contributor Spotlight: Mike (drmikecrypto) — CLI Parser Test Suite & Sensor Driver Documentation

[angeloINTJ]

Every contribution makes SIMUT better. This series highlights the people behind the commits.

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This week: @drmikecrypto

What he built: A host-testable CLI parser extracted from the firmware core, a 20-test unit suite covering every command path, and a complete sensor-driver walkthrough for new contributors.

Why it matters: SIMUT's USB serial CLI has zero authentication. A parser bug can wipe sensor config, change WiFi credentials, or trigger factory reset — all without auth. Before this PR, the parser lived inside CommandManager, a class that depends on Bluetooth, Serial, LittleFS, and a dozen other subsystems. Testing it required hardware or a mountain of stubs.

Mike extracted parseCliCommand() into a standalone CommandParser.cpp with zero I/O dependencies. It compiles on any machine with GCC. The same production code that runs on the Pico W now runs under 20 unit tests in under half a second:

pio test -e native_cli   # 20/20 passed

What the tests cover:

• Empty input, garbage, and three help variants (help, ajuda, ?)
• show system info, show sensors with extra whitespace
• Destructive confirm suffix detection (clear log confirm)
• User management: conf user add/del with and without passwords
• Sensor scan, telemetry server (case-preserving), tel mode (json/csv/custom)
• Sensor slot field with GPIO (sensor 4 tmin -5.0) and invalid GPIO rejection
• Partial commands (conf alone → unknown)
• UTF-8 SSIDs (café-π) and 256-char boundary lines

The documentation: 202 lines in docs/adding-a-new-sensor.md — a practical guide covering the mental model, the 4 touch points needed to add a driver, a step-by-step skeleton following the async state machine pattern, rules learned in production, flash checklist, and in-tree examples (DS18B20, DHT22, BME280).

This closes the tutorial gap from #63 and gives future sensor contributors a clear path.

Stats:

• 8 files changed: +784 / -338 lines
• 20 unit tests in new native_cli environment
• 202-line sensor driver walkthrough
• Zero flash regression (93.1%, unchanged)
• All 29 existing validator tests still pass
• Runs on any machine with GCC — no Pico W required

What the maintainer said:

"You didn't just write code — you built test infrastructure that didn't exist and documented the extension path for future contributors. The CLI parser was a security blind spot (USB without auth) that now has coverage. The refactoring is zero-cost — identical production logic, just testable. This is the kind of contribution that improves project health long-term."

Related: PR #70 · Issue #42 · Issue #63

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