bittty

A pure Python terminal emulator.

Almost usable; some scroll region problems, doesn’t like textual in textual yet.

Demo

Run the standalone demo:

python ./demo/terminal.py

Or use the textual demo to see it in a TUI:

uvx textual-tty

Links

• 🏠 home
• 📖 pydoc
• 🐍 pypi
• 🐱 github

License

WTFPL with one additional clause

1. Don’t blame me

Do wtf you want, but don’t blame me when it rips a hole in your trousers.

Recent changes

• 🏃 squeeze another 15% performance out of it
• ✀ fix utf8 and escape code splitting across buffer boundaries
• 🪟 tests run on Windows runner
• 📉 added parser benchmarking and tui graphs
• 🐌 use regex for parsing to speed things up a tad (~2x faster)
• 📚 document half a billion DEC private modes we don’t support
• 🔙 DECLM - allow \n to act like \r\n so we don’t have to rely on cooked input on the pty when using as a library.
• 🖼️ DEC Special Graphics
• 🐌 Faster colour/style parser
• ⛓️‍💥 Split out from textual-tty into separate package

bugs / todo

• Implement grapheme clustering (thanks Xavier G)
• SIGWINCH handler atomicity + buffer resizes
• architecture - pretty big
• gui
  • make a terminal input class, for standalone input
  • make framebuffer.py
  • choose a display driver
• performance improvements
  • reconsider CSI end char approach
  • line cache for outputs
  • [.] revisit colours / styles
• scrollback buffer
  • implement logloglog for scrollback with wrapping
• bugs
  • scroll region: scroll up in vim corrupts outside scroll region
• add terminal overlay visuals
  • bell flash effect
  • make cursor an overlay
  • make mouse an overlay
  • debug overlay for scroll regions
• Support themes
• bittty-specific escape sequences
  • visible mouse on / off
  • debugging info
  • record
  • list sequences + values
• Document all the escape sequences
  • collect books for a terminal library