Adafruit_GPS/extras/tests

Regression tests

Run every test on Linux with Python 3 and g++:

python3 extras/tests/run_tests.py

The runner discovers every .cpp and .ino in the test subdirectories. Each C++ test supplies main(). Each Arduino sketch supplies setup(), loop(), and a testsPassed flag that remains false until all checks pass. The runner calls setup() and loop() once and returns failure when that flag is false. New tests are picked up automatically without editing CI.

All tests use AddressSanitizer and UndefinedBehaviorSanitizer. Compiler warnings, failed checks, sanitizer findings, and a 30-second execution timeout fail the job. Other tests still run after an individual failure.

The Arduino sketches use the real library sources in four configurations: NMEA_EXTRAS=0 for the basic GPS API and NMEA_EXTRAS=1 for marine extensions, each with NMEA_FLOAT_T=float and NMEA_FLOAT_T=double. Definitions apply consistently to the sketch and library. The RMB test checks that basic builds reject the unsupported sentence and extended builds decode it without partial updates on error. Standalone C++ core tests run once.

extras/test_support provides serial output and a real monotonic clock; the wakeup timeout test takes ten seconds per configuration. I2C, SPI, GPIO, and hardware serial input abort if used. This runs the parser and mock-stream regressions, not physical GPS/SD hardware or MCU emulation. The sketches remain usable on Arduino boards with the normal Arduino core.

Coordinate precision tests preserve all nine retained fractional-minute digits in the GNSS core and distinguish positions about 0.185 mm apart through the GPS double output, including southern latitude and longitude near 180 degrees west. The coordinate-text regression also checks integer-only decimal-degree output with 11 fractional digits, including adjacent retained fractional-minute values and every output capacity. This output preserves detail on AVR without a global float-type override. The submillimeter positions deliberately share the same legacy E7 coordinate. The default float fields and E7 fields are not full-precision RTK outputs. Future receiver APIs and logging examples must preserve the core precision through storage, public results, and formatting without requiring a global float-type override.

The shared position decoder regression checks GGA/RMC/GLL results, independent fix and GGA-quality status, empty/missing fields, exact coordinates through text output, and rejection of malformed sentences without partial measurements. Returned values remain independent of the input buffer and other receivers.

Physical reception tests live separately in extras/hw_tests/gnss_receive. Build and run them explicitly on the documented Nano or HILBERT fixture; the host test runner does not operate attached boards.