Terminfo direct color mode does not work

[commonquail]

Description

System.Console does not print colors correctly under terminal emulators using terminfo's direct color mode (AKA 24-bit, truecolor) entries. I understand that there are several other cross platform issues with System.Console (#52374) but none of those directly identify an issue with recognizing direct color mode.

The key obstacle here is not that System.Console does not have 24-bit color support but rather very specifically that colored text generally ends up illegible. For example, TERM=tmux-direct dotnet run no-such-file. Specifically, colored output by dotnet is how I discovered this.

Reproduction Steps

Using

• the sample program from Bright console colors don't work correctly on Linux #23241
• any direct color mode terminal entry from terminfo
• any 24-bit capable terminal emulator

we can print out many color combinations for different TERM values. For example

$ wget https://raw.githubusercontent.com/mirror/ncurses/master/misc/terminfo.src
$ tic -e tmux-direct,tmux-256color terminfo.src

will download the latest source format terminfo file and install the tmux-direct and tmux-256color entries into the default terminfo database directory. Then

$ for term in tmux-256color tmux-direct ; do TERM=$term dotnet run ; done

will run the program under the different terminfo entries.

Expected behavior

I expect direct color mode terminal entries to behave like 256color entries (given the limitations).

Actual behavior

Tmux 3.1c in Konsole 20.04.2 produces something like

The respective konsole-* entries behave the same, in and out of tmux.

Regression?

No.

Known Workarounds

No response

Configuration

• .NET 6.0.100
• openSUSE Leap 15.3
• x64
• WSL2 exhibits same symptoms

Other information

• There are no test cases for direct color mode entries.
• The max color count record from infocmp is colors#0x1000000.
• Looking at the color pattern it almost seems like some bytes are not being read out of the database.
• My COLORTERM is 1. 0 and unset do not affect this behaviour.

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Issue Details

---

Description

System.Console does not print colors correctly under terminal emulators using terminfo's direct color mode entries. I understand that there are several other cross platform issues with System.Console (#52374) but none of those directly identify an issue with (any kind of) support for direct color mode.

The key obstacle here is not that System.Console does not have 24-bit color support but rather very specifically that colored text generally ends up illegible. For example, TERM=tmux-direct dotnet run no-such-file.

Reproduction Steps

Using

• the sample program from Bright console colors don't work correctly on Linux #23241
• any direct color mode terminal entry from terminfo
• any 24-bit capable terminal emulator

we can print out many color combinations for different TERM values. For example

$ wget https://raw.githubusercontent.com/mirror/ncurses/master/misc/terminfo.src
$ tic -e tmux-direct,tmux-256color terminfo.src

will download the latest source format terminfo file and install the tmux-direct and tmux-256color entries into the default terminfo database directory. Then

Expected behavior

I expect direct color mode terminal entries to behave like 256color entries (given the limitations).

Actual behavior

$ for term in tmux-256color tmux-direct ; do TERM=$term dotnet run ; done

in tmux 3.1c in Konsole 20.04.2 produces something like

The s/tmux/konsole entries behave the same, in and out of tmux.

Regression?

No response

Known Workarounds

No response

Configuration

• .NET 6.0.100
• openSUSE Leap 15.3
• x64
• WSL2 exhibits same symptoms

Other information

There are no test cases for direct color mode entries. Looking at the color pattern it almost seems like some bytes are not being read out of the database.

Author:	commonquail
Assignees:	-
Labels:	area-System.Console, untriaged
Milestone:	-