console-rs / dialoguer

Rust utility library for nice command line prompts and similar things
MIT License
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Backspace behavior at the end of line #292

Open joshka opened 12 months ago

joshka commented 12 months ago

In iTerm2 and Terminal.app on macOS, when the cursor is one past the end of line (i.e. the next character will be entered on the newline), the cursor position is regarded as being on that line rather than then next. When the backspace key is pressed, the logic that handles this case causes the rendering to move to the previous line and start rendering. This means that backspacing over newlines always breaks usages of dialoguer.

I'm not sure if this is a universal problem, a macOS specific issue, or one that is due to some personal random shell setting (I'm not aware of any that would affect this). Is this something others see?

iTerm2

https://github.com/console-rs/dialoguer/assets/381361/d30e58b8-2f6e-4ae9-8b6e-df6ce7d0e55b

Terminal.app

https://github.com/console-rs/dialoguer/assets/381361/278f8150-b493-4eeb-b71f-ee0a49e0ba45

The code in question is https://github.com/console-rs/dialoguer/blob/c5f7c9a59e775e23b74423155ae89342af12c049/src/prompts/input.rs#L333-L337

Repro using VHS:

VHS Tape file ``` Output backspace-eol.gif Set FontSize 32 Set Width 800 Set Height 600 Type "echo Single backspace" Enter Type "cargo run --quiet --example=input" Enter Sleep 2s Type "Test Backspace EOL1" Backspace Sleep 1s Type " Line2" Sleep 2s Ctrl+C Enter Sleep 2s Type "echo Double backspace" Enter Type "cargo run --quiet --example=input" Enter Sleep 2s Type "Test Backspace EOL12" Backspace 2 Sleep 2s Type " Line2" Enter Ctrl+C Enter Sleep 2s Type "echo Triple backspace" Enter Type "cargo run --quiet --example=input" Enter Sleep 2s Type "Test Backspace EOL123" Backspace 3 Sleep 2s Type " Line2" Enter Ctrl+C Sleep 2s ```

backspace-eol