Statusline/Tabline - Unable to see which buffer is open when many buffers are open in a tab

Question

I have a tab with the following window structure:

_________________________________
1              | 3               |
               |                 |
               |                 |
_______________|_________________|
4              | 5               | 
               |                 |
               |                 |
_______________|_________________|

Numbers indicated the buffer numbers provided automatically by vim. I have vim-airline that I was hoping would help me figure out which window I am currently focused on and which buffer I am editing. Please see gif here, reproduced below:

Buffer 1 is .vimrc, 3 is Main1.cpp, 4 is include1.h and 5 is include2.h.

As I move clockwise, the tabline in the bottom of each window gets highlighted indicating which window I am focussed on. However, the tabline does not work properly in buffers/windows 1 and 3. Essentially, in 1 (especially) and 3, I do not get to see 1:.vimrc and 3:Main1.cpp in the tablines for these specific windows clearly because the available space is crowded/joslted out unnecessarily for these windows by 4:include1.h and 5:include2.h, which are irrelevant in these windows. Is there a way that the tabline can highlight the buffer name completely even if there are other buffers jostling for space on the same tabline?

Because this could be behavior due to possibly some plugins that I have, in the image above, buffer 1 lists all the plugins I have currently installed.

Is there a way to fix this?

Answer 1

After looking through ways of customizing the vim-airline status line, and also looking at how default vim's inbuilt status lines work, I have ended up using the following in my .vimrc

let g:customstatusline = 0 " can be 0 or 1

if g:customstatusline == 0
  let g:airline#extensions#tabline#enabled = 1
  let g:airline_section_c='%f %m %{tagbar#currenttag("%s ","","f")} %l of %L %P'
  let g:airline_section_x=''
  let g:airline_section_y=''
  let g:airline_section_z=''
else
  set laststatus=2
  set statusline=%f\ %m%{tagbar#currenttag('%s\ ','','f')}%l,%L\ %P
  let g:bufferline_active_buffer_left = '[[['
  let g:bufferline_active_buffer_right = ']]]'
endif

In the case of g:customstatusline==0, I provide a very minimal vim-airline that includes the filename of the current buffer only, whether it is modified or not, the current symbol cursor is in (requires tagbar plugin), which line the cursor is on currently, how many total lines are in the buffer and what percentage of movement within the buffer is covered. Sections x, y and z of the status bar are set to null values. This works for me.

I also found my own custom setting of the status line can also do the job. That is the else case. Here, I display the same content as the case above. The currently active buffer is visually highlighted thus: [[[ currently_active_buffer ]]]