Fix DEC special graphics lower-right corner#11
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Pull request overview
This PR fixes an incorrect DEC Special Graphics (VT100 line drawing) character mapping so terminal apps render box corners correctly, and adds a regression test that exercises the actual ESC ( 0 / ESC ( B charset-switching path.
Changes:
- Correct DEC Special Graphics mapping for
jto the Unicode lower-right corner (U+2518). - Add a regression test verifying corner/line glyph mappings and that switching back to ASCII restores literal output.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.
| File | Description |
|---|---|
src/XTerm.NET/Common/Charsets.cs |
Fixes the DEC Special Graphics j mapping to the correct lower-right corner glyph. |
src/XTerm.NET.Tests/InputHandlerTests.cs |
Adds a regression test covering ESC ( 0 charset selection, line-drawing output, and ASCII reset behavior. |
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tomlm
approved these changes
Jun 22, 2026
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Summary
jfrom top-left corner to lower-right corner.ESC ( 0parser path and verifies the corner, line, and ASCII-reset behavior.Why
VT100/xterm DEC Special Graphics maps
jto the lower-right box-drawing corner. XTerm.NET was mapping it to the top-left corner, so terminal applications that use DEC line drawing could render boxes with the wrong corner glyph.Validation
dotnet test src\XTerm.NET.slnxEscapeSequenceParser.DcsandTerminal.HyperlinkChanged.