Feature Request: Jump back from definition

[inv2004]

I was trying to use micro the lsp, it works fine,
except that I cannot find any bind or command like ctrl-o in vim: go back

Could you please let me know if I missed something?

ctrl-i: go forward - would be perfect also sometimes

Thank you

[ElectricRCAircraftGuy]

Is this a feature request?

I wonder if a plugin exists to do this.

[inv2004]

@ElectricRCAircraftGuy It is just a question, maybe I did not find it. If it does not exist - would be good to have

--edit--
added feature request in the header

[dmaluka]

Micro has no built-in LSP support. I guess you are using this lsp plugin: https://github.com/AndCake/micro-plugin-lsp, right? Then probably https://github.com/AndCake/micro-plugin-lsp is the place for your feature request.

While we're at it, FWIW, besides this plugin, there is also an old experimental lsp branch by @zyedidia adding some initial LSP support to micro as a built-in functionality: https://github.com/zyedidia/micro/commits/lsp. But it's probably pretty outdated, and I barely know anything about it (or about LSP in general, for that matter).

[inv2004]

@dmaluka Thank you for initial explanation. I did not think that the back/forward is related to lsp plugins. like in vim - you have jump history unrelated any plugin (if I understand it right)

[dmaluka]

Ah ok, you originally mentioned lsp, so I was thinking that you were referring to jumping back in the context of using lsp, i.e. jumping back after jumping to a definition via the lsp plugin (i.e. similar to vim's Ctrl-T for jumping back in the tag stack, after jumping to a tag via Ctrl-]). This kind of jump is not supported natively by micro just because micro has no built-in notion of "definition".

Now, when it comes to jumping back after any kind of jump, without distinguishing whether it was a definition jump or a search or just a jump to the end of file and so on, i.e. as with vim's Ctrl-O (not Ctrl-T), then micro doesn't have this functionality either, but I actually think it should be not too difficult to implement it: now that my PR #2628 got in, micro has a notion of "jumping far-away", so we can implement a stack of such far-away jumps, for jumping back or forward.

In the meantime, I'm personally not in a strong need for such feature, since I'm using my nav plugin: https://github.com/dmaluka/micro-nav for jumping to definitions (it is tags based like in vim, you may think of it as a poor man's lsp) and it already provides the functionality of jumping back after jumping to a definition. It covers most of my needs so it's good enough for me at the moment (although it would be nice to be able to jump back after other kinds of jump as well, e.g. after a search).

[inv2004]

@dmaluka I checked the code of the nav plugin and it seems reasonable for me that I can try to patch lsp to have the same functionality ... if someone from micro would decide to have to jumplist.

Also, I checked the #2628 and looks like that it is near, but do not match the simple vim rules like goto, go line, because of the 25%, but I did not read the PR's code very detailed

[dmaluka]

Regarding #2628, my point is that it introduces BufPane's GotoLoc method which is now supposed to be used for "long jumps" i.e. for such cursor movements that may move the cursor far away (in contrast to "short jumps" like moving cursor to the end of current line and so on). Currently the only purpose of BufPane's GotoLoc is to move the view so that the new cursor location after a "long jump" is at 25% of the screen height. But we can extend it to serve other useful purposes as well, like remembering the history of "long jumps" for jumping back and forth between them.

[masmu]

I would be also pretty interested in this. Currently I am working on a draft for my own history plugin to monitor cursor movement and jumps (short and long ones).
The way it is suppose to work right now is that it binds to all the preCursorX methods and puts the cursor locations on a stack.
When you trigger a HistoryBackward method it pops an element from the stack and jumps to its location. So far so good.

But there are certain issues with that solution:

1. When other plugins use GotoLoc this isn't being monitored since GotoLoc is not a bind-able action and therefore you cannot hook into preX and onX events.
2. Insertion of new lines or pasting of code blocks messes up the stored locations on the stack.
3. Keybindings that trigger chained actions do not work great with this concept since each action is stored individually on the stack. ("CtrlUp": "CursorUp,CursorUp,CursorUp,CursorUp,CursorUp") So you press Ctrl+Up which moves the cursor 5 lines up but when triggering HistoryBackward it jumps down one line instead of five.

Maybe doing this as a plugin isn't the way to go?

So I thought of the acceptance criteria for an implementation that makes no compromises (from my POV).

• Implement 2 bind-able actions: HistoryBackward and HistoryForward.
• Aggregate short and long cursor movements / jumps based on time. So store a location when the user didn't trigger any other cursor movement for longer than X seconds. Or store them all but pop locations from the stack until a certain time limit is reached and just jump to the last popped one. (Solves my 2nd problem)
• This works over all Bufpanes. The appropriate Bufpane is being selected and activated for the cursor movement being undone. Already closed Bufpanes are being reopened when possible.
• Inserted or deleted lines are being taken into account to keep the cursor movement consistent.

Feel free to extend this list in case I missed something.

Micro is already pretty awesome. My main problems with it are all navigation issues.
I found at least 2 issues asking for this feature (this issue and #1563) and IMHO this is a feature you can expect from a mature editor. So, this might be a thing worthy to invest some time on.
What do you think?

[dmaluka]

Extending GotoLoc with a native support for jump history sounds attractive to me (after all, I myself suggested it in the past in my comment above). I do often miss this functionality, for example, when I'm jumping to the beginning of a file (e.g. to see what headers are included) and want to return back shortly after that (and thus I would like micro to remember this last location I want to return to).

On the other hand, implementing it the way you suggest (time based jumps, cross-bufpane jumps and so on) means a lot of complication, and also may not be unequivocally desired by all users. For instance, I as a user am not interested in short jumps, I want micro to only remember long jumps, and don't want it to jump between bufpanes.

So maybe at least initially it's better to experiment with all that in a plugin.

So, regarding the difficulties you mentioned:

• When other plugins use GotoLoc this isn't being monitored since GotoLoc is not a bind-able action and therefore you cannot hook into preX and onX events.

Since recently there is onAnyEvent callback which should allow detecting any jumps, just by comparing the current cursor location with the last one.

• Insertion of new lines or pasting of code blocks messes up the stored locations on the stack.

There is onBeforeTextEvent callback (unfortunately still not documented) executed before any insertion or removal of a text. Its first argument is the Buffer, its second argument is a TextEvent structure with the information about the insertion or removal.

• Keybindings that trigger chained actions do not work great with this concept since each action is stored individually on the stack. ("CtrlUp": "CursorUp,CursorUp,CursorUp,CursorUp,CursorUp") So you press Ctrl+Up which moves the cursor 5 lines up but when triggering HistoryBackward it jumps down one line instead of five.

Again, onAnyEvent should not be prone to this problem.