Package index filename is truncated if it contains `.`

[per1234]

Describe the problem

If the filename of a package index contains the character ., Arduino CLI truncates the downloaded filename

To reproduce

$ arduino-cli version

arduino-cli.exe  Version: git-snapshot Commit: 6aa1be03 Date: 2023-09-28T08:02:22Z

$ export ARDUINO_DIRECTORIES_DATA="/tmp/arduino-cli-directories/data"  # Use a throwaway directories.data for the demo

$ arduino-cli  --additional-urls http://drazzy.com/package_drazzy.com_index.json core update-index

[...]
Downloading index: package_drazzy.com_index.json downloaded
Error initializing instance: Loading index file: loading json index file C:\Users\per\AppData\Local\Temp\arduino-cli-directories\data\package_drazzy.com_index.json: open C:\Users\per\AppData\Local\Temp\arduino-cli-directories\data\package_drazzy.com_index.json: The system cannot find the file specified.
[...]

$ ls "$ARDUINO_DIRECTORIES_DATA"/package_drazzy*.*

/tmp/arduino-cli-directories/data/package_drazzy.json

$ arduino-cli  --additional-urls http://drazzy.com/package_drazzy.com_index.json core install ATTinyCore:avr
Error initializing instance: Loading index file: loading json index file C:\Users\per\AppData\Local\Temp\arduino-cli-directories\data\package_drazzy.com_index.json: open C:\Users\per\AppData\Local\Temp\arduino-cli-directories\data\package_drazzy.com_index.json: The system cannot find the file specified.
Error initializing instance: Loading index file: loading json index file C:\Users\per\AppData\Local\Temp\arduino-cli-directories\data\package_drazzy.com_index.json: open C:\Users\per\AppData\Local\Temp\arduino-cli-directories\data\package_drazzy.com_index.json: The system cannot find the file specified.
Invalid argument passed: Platform 'ATTinyCore:avr' not found

🐛 The downloaded package index was named package_drazzy.json instead of the correct name package_drazzy.com_index.json

🐛 The platforms from the package index can't be installed because the truncation caused the file to no longer have the required filename format (package_<differentiator>_index.json).

Expected behavior

The filenames of package index files are not changed on download.

Arduino CLI version

6aa1be0

Operating system

• Windows
• Linux

Operating system version

• Windows 11
• Ubuntu 22.04

Additional context

I bisected the regression to 82e6f5d (doesn't occur when using the build from the previous commit 1877431).

---

The use of a full domain name in the package index filename is explicitly recommended in the Arduino Package Index Specification:

https://arduino.github.io/arduino-cli/dev/package_index_json-specification/#naming-of-the-json-index-file

We suggest using a domain name owned by the packager. For example:

package_arduino.cc_index.json

---

Originally reported at SpenceKonde/ATTinyCore#803 (comment)

Additional reports

• Arduino IDE 2.2.1 Board Manager Fails to Add SpenceKonde/megaTinyCore#1005
• 'ATTinyCore by Spence Konde' doesn't show in Board Manager list SpenceKonde/ATTinyCore#802

Related

• Hack fix for arduino-cli issue with megatinycore BSP URL adafruit/ci-arduino#163

Issue checklist

• I searched for previous reports in the issue tracker
• I verified the problem still occurs when using the nightly build
• My report contains all necessary details