use pio native to build standalone

platformio.ini

@@ -2,8 +2,9 @@
 ; override any settings with your own local ones in pio_local.ini
 
 [platformio]
-default_envs = esp32_4M
+; default_envs = esp32_4M
 ; default_envs = esp32_16M
+default_envs = standalone
 
 extra_configs = 
   factory_settings.ini
@@ -16,8 +17,8 @@ core_build_flags =
   -D NDEBUG
   -D ARDUINO_ARCH_ESP32=1
   -D ESP32=1
-  ; -std=gnu++17
-  ; -Os
+  -std=gnu++17
+  -Os
 
 ; core_unbuild_flags = -std=gnu++11 
 ; core_unbuild_flags = -std=gnu++17 
@@ -40,7 +41,6 @@ unbuild_flags =
   ${common.core_unbuild_flags}
 
 [env]
-framework = arduino
 monitor_speed = 115200
 monitor_raw = yes
 upload_speed = 921600
@@ -58,6 +58,7 @@ check_flags =
 [env:ci]
 extra_scripts = scripts/rename_fw.py
 board = esp32dev
+framework = arduino
 platform = espressif32
 board_build.partitions = esp32_partition_4M.csv
 board_build.filesystem = littlefs 
@@ -69,6 +70,7 @@ extra_scripts =
   pre:scripts/build_interface.py
   scripts/rename_fw.py
 board = esp32dev
+framework = arduino
 platform = espressif32
 board_upload.flash_size = 4MB
 board_build.partitions = esp32_partition_4M.csv
@@ -80,6 +82,7 @@ extra_scripts =
   pre:scripts/build_interface.py
   scripts/rename_fw.py
 board = esp32dev
+framework = arduino
 platform = espressif32
 board_upload.flash_size = 16MB
 board_build.partitions = esp32_partition_16M.csv
@@ -91,6 +94,7 @@ extra_scripts =
   pre:scripts/build_interface.py
   scripts/rename_fw.py
 board = lolin_c3_mini
+framework = arduino
 platform = espressif32
 board_upload.flash_size = 4MB
 board_build.partitions = esp32_partition_4M.csv
@@ -104,6 +108,7 @@ extra_scripts =
   pre:scripts/build_interface.py
   scripts/rename_fw.py
 board = lolin_c3_mini
+framework = arduino
 platform = espressif32
 board_upload.flash_size = 4MB
 board_build.partitions = esp32_partition_4M.csv
@@ -115,8 +120,42 @@ extra_scripts =
   pre:scripts/build_interface.py
   scripts/rename_fw.py
 board = lolin_s2_mini
+framework = arduino
 platform = espressif32
 board_upload.flash_size = 4MB
 board_build.partitions = esp32_partition_4M.csv
 build_flags = ${common.build_flags}
 build_unflags = ${common.unbuild_flags}
+
+; see https://docs.platformio.org/en/latest/platforms/native.html#id1
+; to build: pio run -e standalone
+; to run and build: pio run -e standalone -t exec
+[env:standalone]
+platform = native
+build_flags =
+	-DARDUINO
+  -DARDUINOJSON_ENABLE_STD_STRING=1 -DARDUINOJSON_ENABLE_PROGMEM=1 -DARDUINOJSON_ENABLE_ARDUINO_STRING -DARDUINOJSON_USE_DOUBLE=0 
+  -DEMSESP_DEBUG -DEMSESP_STANDALONE -DEMSESP_USE_SERIAL
+  -DEMSESP_DEFAULT_LOCALE=\"en\" -DEMSESP_DEFAULT_TX_MODE=8 -DEMSESP_DEFAULT_VERSION=\"3.5.0-dev\" -DEMSESP_DEFAULT_BOARD_PROFILE=\"S32\"
+	-lpthread
+  -std=gnu++17 -Og -ggdb
+build_src_flags = 
+  -Wall -Wextra -Werror -Wswitch-enum -Wno-unused-parameter -Wno-inconsistent-missing-override
+  -I./lib_standalone
+  -I./lib/ArduinoJson/src
+  -I./lib/uuid-common/src
+  -I./lib/uuid-console/src
+  -I./lib/uuid-log/src
+  -I./lib/semver
+  -I./lib/PButton
+build_src_filter =
+	+<*>
+  -<.git/>
+  +<../lib_standalone>
+  +<../lib/uuid-common>
+  +<../lib/uuid-console>
+  +<../lib/uuid-log>
+  +<../lib/semver>
+  +<../lib/PButton>
+lib_compat_mode = off
+lib_ldf_mode = off