Incorrect syntax highlighting after some preprocessor directives

[yodapuces63]

Describe the problem

After #elif and #error, the text are wrong coloured
see de screenshot

To reproduce

Copy this in editor

//---Config pour l'ESP-----------------------
#ifdef ARDUINO_ESP8266_GENERIC
  #define ESPMOD      //pour module ESP12
  #define TelNetDEBUG       //mode TelNet debug (via port 23)
//#define CommErTRACE         //TRACE les compteurs d'erreures de comm

//---Config pour le ProMini------------------
#elif ARDUINO_AVR_PRO
  #define PROMOD      //pour module ProMini

#else
  #error              //Si pas une de ces deux carte => Stop la compilation
#endif

Expected behavior

#elif definition should be blue
#error //comment should be green

Arduino IDE version

2.0.1

Operating system

Windows

Operating system version

10

Additional context

Additional reports

• https://forum.arduino.cc/t/ide-frontend-problems/1254933

Issue checklist

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

[per1234]

Thanks for your report @yodapuces63.

This is an upstream bug that originates in the "TextMate" grammar hosted here:

https://github.com/jeff-hykin/better-cpp-syntax

That grammar is used by the "C/C++ Language Basics" extension built-in to VS Code and the Eclipse Theia IDE framework Arduino IDE 2.x is built on.

As they explain here, the fixes must first be made in the originating repository, from which they would eventually propagate to Arduino IDE through the dependency chain:

"This file has been converted from https://github.com/jeff-hykin/cpp-textmate-grammar/blob/master/syntaxes/cpp.tmLanguage.json",
"If you want to provide a fix or improvement, please create a pull request against the original repository.",
"Once accepted there, we are happy to receive an update request."

There are two separate issues here, both of which I verified also occur with v1.16.3 of the "Better C++ Syntax" extension installed in VS Code:

Inconsistent highlighting of expression following #elif directive

Minimal demonstration code:

#define FOO false
#define BAR false

#if FOO  // Coloration of expression is as expected

#elif BAR  // Coloration of expression is NOT as expected

#endif

I see there is an existing report here: jeff-hykin/better-cpp-syntax#532

Incorrect highlighting of comments following #error/#warning directives w/o message

Minimal demonstration code:

// Normal comment coloration

#warning foo  // Coloration of comment is as expected

#warning  // Coloration of comment is NOT as expected

#error bar  // Coloration of comment is as expected

#error  // Coloration of comment is NOT as expected

I did not find an existing report about this in the upstream repository, so I submitted one: jeff-hykin/better-cpp-syntax#611