Add NERDTreeRefreshRoot command

[wgfm]

Implements #727

[PhilRunninger]

@wgfm, thanks for the contribution. It appears you have some more work to do. While it works when NERDTree is the active window, if my active window is anything else, I get this error.

NERDTree: Refreshing the root node. This could take a while...
Error detected while processing function <SNR>47_refreshRoot:
line    2:
E121: Undefined variable: b:NERDTree
line    3:
E121: Undefined variable: b:NERDTree
NERDTree: Refreshing the root node. This could take a while... DONE
NERDTree: Refreshing the root node. This could take a while...
NERDTree: Refreshing the root node. This could take a while... DONE

Also, make sure the help file include a description of the new command.

[wgfm]

Ah, I see. It's because NERDTree is scoped to that particular buffer. I do not want to be invasive, nor do I have extensive knowledge of the codebase and vimscript. Would you have some pointers for a possible approach I could take?

I'd also understand if you don't have the time to guide me through this.

[PhilRunninger]

You've chosen a complicated program with which to learn vimscript, but that's OK. The plugin is written in a style that mimics object-oriented programming as much as a scripting language can. There is a global "object" you can access from any window. It is g:NERDTree, and the code is in lib/nerdtree/nerdtree.vim. I suggest you write a new function there that does the following:

1. Return if NERDTree is not open.
2. Get the current window.
3. Switch to the NERDTree window.
4. Refresh it.
5. Switch back to the original window.

The pieces are all there in that file's other functions and in the s:refreshRoot() function of ui_glue.vim.

Don't forget to change your command! ... NERDTreeRefreshRoot... to call your new function.

Give it another try. This shouldn't be too hard, and if you get stuck, I can help you out.

[wgfm]

I've added a g:NERDTree.RefreshRoot() function. There's a couple of things I'm not really sure about.

1. Should the redraw happen in ui_glue?
2. Should we call the new function from s:refreshRoot() to reduce duplication?
3. The doc entry is quite short, but then again, there's not a lot going on that would require longer documentation.

[PhilRunninger]

I gave this another thought after your questions, and there is a better way to do this, which directly answers your second question. Fortunately, it's a simple change from what you have now. The new function you wrote in lib/nerdtree/nerdtree.vim can be moved to ui_glue.vim to replace the s:refreshRoot() function. Just keep the nerdtree#echo() function calls, and use g:NERDTree instead of s:NERDTree.

[PhilRunninger]

Leave this at 4 space indent.

[wgfm]

I have implemented the requested changes. Now, there are two unnecessary window switches happening when the root is refreshed while NERDTree is the current buffer.

[PhilRunninger]

@wgfm, one more change, and this will be ready to merge. Regarding your comment about switching windows unnecessarily, the way you've written it is fine. The wincmd w command recognizes that the cursor is already in the specified window, and won't do anything.

[wgfm]

@PhilRunninger, thank you so much for your time. Much appreciated!

[thinker3]

I use vim ., but now press R can't refresh root, I have to checkout 6b6cadf : 2018-10-10 22:19