On Mon, 31 Mar 2025 17:22:45 GMT, David M. Lloyd <d...@openjdk.org> wrote:
>> The `java.io.Console` has several backends: a simple on in `java.base`, a >> more convenient one in `jdk.internal.le` (with line-reading based on JLine) >> and one for JShell. >> >> The backend based on JLine is proving to be a somewhat problematic - JLine >> is very powerful, possibly too powerful and complex for the simple task of >> editing a line with no completion, no history, no variables, no commands, >> etc. As a consequence, there are inevitable sharp edges in this backend. >> >> The idea in this PR is to replace the use of JLine in the `jdk.internal.le` >> backend with a simple escape code interpreter, that only handles a handful >> of keys/codes (left/right arrow, home, end, delete, backspace, enter), and >> ignores the rest. The goal is to have something simple with less surprising >> behavior. > > src/jdk.internal.le/share/classes/jdk/internal/console/SimpleConsoleReader.java > line 75: > >> 73: } >> 74: continue READ; >> 75: case '\033': > > If this is meant to be platform-agnostic, is it really safe to make these > assumptions about the ability to produce or interpret escape codes and to > make assumptions about their behavior on the user's terminal? I don't think > it would even be safe to assume a single terminal type or interpretation on > POSIX-type OSes; that's what things like `terminfo`/`termcap` are supposed to > be for, right? In theory, yes, that's what `terminfo` is supposed to do. But `terminfo` has its own set of problems, and what we get from a terminal and what we send to the terminal is so simple and generally supported, that it should be possible to make it work on all realistic terminals(*). Or is there a particular terminal you have in mind? (*) I admit I've forgot that `\E[7~`/`\E[8~` is Home/End as well. I'll fix that. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/24242#discussion_r2022656839
