Series of checks + warnings for PlatformIO when working with ATtiny84 platform, to ensure you're using the correct CW/CCW pinmapping

ATtinyX4_pinmap_warnings.cpp

// Warnings to ensure ATtinyX4's Arduino pinmapping is defined correctly
#ifdef __AVR_ATtinyX4__ // ensure ATtinyX4 platform, proceed with warning checks

// SETUP: Uncomment ONE of the two definitions below to select the desired pinmapping:
#define USE_CW_PINMAPPING // this project uses CLOCKWISE (CW) pinmapping
// #define USE_CCW_PINMAPPING // this project uses COUNTERCLOCKWISE (CCW) pinmapping

#ifdef USE_CW_PINMAPPING
#ifdef USE_CCW_PINMAPPING
#error "Both CW and CCW pinmappings are specified - only one may be selected!"
#else
#ifdef PINMAPPING_CCW
#error "Project uses CW pin mapping, but CCW pinmapping is defined! Ensure ini board_build.variant is tinyX4_reverse (optional if board is attiny84_cw_pinmap), or omitted (if board is attiny84)"
#else
#ifndef PINMAPPING_CW
#error "Project uses CW pin mapping, but PINMAPPING_CW is undefined! Ensure ini board_build.variant is omitted (if board is attiny84), or that it's tinyX4 (optional, or if board is attiny84_cw_pinmap)"
#endif
#endif
#endif
#else
#ifndef USE_CCW_PINMAPPING
#error "Neither CW or CCW pinmappings are specified - one must be selected!"
#else
#ifdef PINMAPPING_CW
#error "Project uses CCW pin mapping, but CW pinmapping is defined! Ensure ini board_build.variant is omitted (if board is attiny84), or that it's tinyX4 (optional, or if board is attiny84_cw_pinmap)"
#else
#ifndef PINMAPPING_CCW
#error "Project uses CCW pin mapping, but PINMAPPING_CCW is undefined! Ensure ini board_build.variant is tinyX4_reverse (optional if board is attiny84_cw_pinmap), or omitted (if board is attiny84)"
#endif
#endif
#endif
#endif
// for more info see: https://github.com/SpenceKonde/ATTinyCore/blob/77ae92aafb2294f9838c3e15575c2b5477066439/avr/extras/ATtiny_x4.md#pin-mapping-options
#endif // --- end pinmapping warnings