"Up" key should recall previously entered command instead of previous command from history

[develop7]

Repro:

1. execute echo foo
2. execute <Space>echo bar (prepend command with a space ( ) to prevent storing it in history)
3. press ↑ key

Expected: <Space>echo bar is recalled

What happens instead: echo foo is recalled

This behavior is very convenient if a user wants to try various approaches to run command but doesn't want to flood history with non-working entries and/or entries containing private data.

[develop7]

Is something wrong with this issue? if so, where should I start to make it look better? Thanks.

[zanchey]

Reframed, this is a request for both universal and global history, where only universal history is saved to disk or visible to other shells. I am not sure that it is a good idea.

Fish already ignores commands that exit with a non-zero status when saving them to the history, which helps to avoid polluting it with error-prone entries.

[ridiculousfish]

I don't think fish ignores commands that exit with non-zero status?

[zanchey]

No, it doesn't - apologies. That is issue #5. It only ignores nonexistent commands.

[ridiculousfish]

It looks like bash and zsh behave in the way that the originator describes. It doesn't make a whole lot of sense to me either though.

[develop7]

@ridiculousfish @zanchey looks like you're ok with polluting shell history with volatile entries in order to enable user to reuse previous command (that's a use case for this feature too)?

bash and zsh behave in the way that the originator describes

not sure of bash, but zsh does indeed

[zanchey]

It might be worth having a read of some of the discussion in #940, where I think we have covered some of the ideas behind this request.

[develop7]

I've added another possible use case to issue description.

Also since core team is not sure if they want to see this implemented, I've got a question: would be accepted a pull request implementing this feature?

[ridiculousfish]

zsh says:

Note that the command lingers in the internal history until the next command is entered before it vanishes, allowing you to briefly reuse or edit the line. If you want to make it vanish right away without entering another command, type a space and press return.

So there's at most one volatile entry in zsh. That's an interesting compromise. What do you think?

[develop7]

@ridiculousfish I'm perfectly ok with just one entry. Sorry for not being clear enough, I was sure I was.

[pickfire]

What is the progress on this?

[alphapapa]

I'm not sure this is a good idea. When I prefix a command with a space, it's because I do not want the command recorded. If this change were made, I would have to kill the fish process, or the command would remain in that shell's history.

At the least, this feature should be optional, and off by default.