`lem -i webview` tries to opens ncurses instead

[matchatealeaf]

To reproduce:

git clone https://github.com/lem-project/lem.git
cd lem && make webview
sudo make install
lem -i webview

debugger invoked on a SIMPLE-ERROR in thread
#<THREAD tid=32533 "main thread" RUNNING {1200048003}>:
  implementation NCURSES not found

Type HELP for debugger help, or (SB-EXT:EXIT) to exit from SBCL.

restarts (invokable by number or by possibly-abbreviated name):
  0: [ABORT] Exit from the current thread.

(LEM-CORE:LAUNCH #S(LEM-CORE::COMMAND-LINE-ARGUMENTS :ARGS NIL :HELP NIL :DEBUG NIL :VERSION NIL :WITHOUT-INIT-FILE NIL :LOG-FILENAME NIL :INTERFACE :NCURSES :FILENAMES NIL))
   source: (ERROR "implementation ~A not found" IMPLEMENTATION-KEYWORD)
0] 

This also breaks launching the .desktop file as it uses lem -i webview.

If we build both webview and ncurses instead,

make webview-ncurses
sudo make install
lem -i webview

Lem opens the ncurses version.

Running lem without -i webview works and opens the webview version successfully.

[ethanxxxl]

It looks like this issue was possibly introduced in 9eecc3f when the entry point was switched from lem:main to lem-webview:main in lem.asd.

[ethanxxxl]

I solved this issue in PR #2074

[matchatealeaf]

I solved this issue in PR #2074

Thanks. I can confirm that lem -i webview indeed opens the webview version now, when built with make webview or make webview-ncurses.

However, it no longer detects versions that are not installed.
For example,

make webview
./lem -i ncurses

opens webview instead of raising an error about the ncurses version not being installed.

This also happens for other combinations: make ncurses; ./lem -i webview which opens ncurses or make sdl2; ./lem -i ncurses which opens sdl2 etc.

We can also do

make webview
./lem -i adfjadsf

where adfjadsf is some random string, and it will still open webview.

It looks like this is intentional due to the setting of an implementation fallback in get-default-implementation in interface.lisp.
I'm not sure if this is good behavior, but feel free to close this if this is fine.

[ethanxxxl]

Yes, I intentionally added that behavior. I felt that it would be useful to have Lem open in some capacity if possible. If we would rather have Lem not open and instead print what options are available, that also makes sense to me. I think if we keep the current functionality, an editor warning should be displayed on startup. It currently spits out a warning in the logs, but you would have to explicitly look at the log file to see it. Having a message pop up explaining that -i adfjasdf is not a valid interface and Lem opened in its default configuration might help the behavior seem less obscure.