arduino-esp32littlefs-plugin

Please use the universal combined plugin for all FS instead of this one.

Arduino ESP32 LittleFS filesystem uploader

Arduino plugin, which packs sketch data folder into LittleFS filesystem image and uploads the image to ESP32 flash memory
Everything is kept identified as SPIFFS for compatibility with your previous code like drop-in replacement
Same partition scheme and "data" folder is used
You can use either LITTLEFS or SPIFFS but not both simultaneously on given Arduino project
The LITTLEFS library for arduino-esp32 core is here
A PR to embed it to esp32 core is made, too. See the PR status here

Make sure you use one of the supported versions of Arduino IDE and have ESP32 core installed.
Download the tool archive from here
In your Arduino sketchbook directory, create tools directory if it doesn't exist yet.
Copy the tool into tools directory (the path will look like <home_dir>/Arduino/tools/ESP32LittleFS/tool/esp32littlefs.jar).
You need mklittlefs tool Download the release
Copy it to /tools folder of esp32 platform where espota and esptool (.py or.exe) tools are located
Restart Arduino IDE.

On the OS X create the tools directory in ~/Documents/Arduino/ and unpack the files there

Open a sketch (or create a new one and save it).
Go to sketch directory (choose Sketch > Show Sketch Folder).
Create a directory named data and any files you want in the file system there.
Make sure you have selected a board, port, and closed Serial Monitor.
Select Tools > ESP32 LittleFS Data Upload menu item. This should start uploading the files into ESP32 flash file system.

When done, IDE status bar will display LITTLEFS Image Uploaded message. Might take a few minutes for large file system sizes.

This work is based on the original tool Copyright (c) 2015 Hristo Gochkov (hristo at espressif dot com)
Licensed under GPL v2 (text)
ESP8266 variant of same tool, made by earlephilhower is here
ESP8266 variant of LittleFS libraty, same author: see here

Install Java JDK
Find the path of javac.exe and jar.exe
Edit make_win.bat accordingly
Copy files arduino-core.jar , commons-codec-1.7.jar , pde.jar from your Arduino IDE installation to the folder where is located make_win.bat
Run make_win.bat
Find the build jar in /bin directory