Can't highlight a single character

[JS-Zheng]

vim-highlighter version: 0e19263 vim version: 8.2.4700

When entering to the visual mode and selecting a single character, :HiSet will generate empty pattern (i.e., \V) , causing Vim highlights all characters.

[azabiong]

Hi Jason, Thank you for finding this error and opening the issue. I think now the new version 1.39.9 will solve this problem.

[JS-Zheng]

Hi Azabiong, thanks for creating such a useful plug in! It helps me fight many annoying logs. But this issue still exists, the highlight of the single-character cannot work properly.

I think this issue is caused by the following statement in s:GetVisualLine() function:

  if l:left == l:right | return '' | endif

Therefore, I open a pull request #8, for your reference only, to try to solve this issue and this approach can introduce new multi-line highlight feature, by the way.

IMHO, both features (i.e., multi-line, single-char highlight) are very useful. However, some existing features (e.g., HiFind, HiErase) may be affected and still need further verification.

[azabiong]

Hi Jason, Thank you very much for your update! It's looks very good! 👍 Could you please upload this text block or send it to me so I can check it?

[azabiong]

And yes, as you noted, support for multiline highlighting is not ready yet. However it's in the future upgrade list.

[JS-Zheng]

My pleasure 😀 That Apache log is adapt from elastic/example project.

[azabiong]

Thank you, I downloaded it. Now, how should I reproduce it or which char should I select?

[JS-Zheng]

Reproduce:

• v (select single character)
• f<CR> (HiSet mapping)

You can choose any single character and not limited to the question mark (i.e., ?). IMHO, you don't need to download that example log, and you can open any text file for testing :)

[azabiong]

Thank you, I'm using 1.39.9, but I couldn't reproduce 1.39.8 symptom... 😅 What should I do...

[JS-Zheng]

Could you highlight a single character in 1.39.9?

In my test (following above reproduce steps):

• v1.39.9: Do nothing (due to s:GetVisualLine() returns a empty string)
• v1.39.8: Highlight everything (due to the pattern is \V)

[azabiong]

Yes, I can highlight single characters in 1.39.9 using v and moving cursor to right l and f enter.

[azabiong]

It seems that v1.39.8 \V was the root cause. If so, I think 1.39.9 will fix that. What do you think?

[JS-Zheng]

What's your 'selection' (i.e., 'sel') setting in Vim? My sel value is 'inclusive', so I don't need to moving cursor left/right after using v.

I guess it may be the problem in s:GetVisualLine():

...
if l:left == l:right | return '' | endif    <----- **this line doesn't consider &selection**
if l:right > 0                                     
  let l:right -= &selection == 'inclusive' ? 1 : 2 
endif   
...                                           

[azabiong]

Wow, you find the issue very quickly! 👍 My selection setting is exclusive, and it shows the difference, as you mentioned!

[JS-Zheng]

My pleasure 😀, very glad to improve this awesome project!

[azabiong]

I think now v1.40 will resolve the issue. It seems to select unicode characters correctly too 😁 I added your name to Credits section h: Hi-Credits

[JS-Zheng]

It works well! Thanks! 😆

[azabiong]

Hi Jason, now Jump to Highlights feature is supported, and I think it can be useful when you analyze logs 😄

[JS-Zheng]

Wow! Great feature and efficient development You're so thoughtful, thanks 😆

[JS-Zheng]

Hi @azabiong, some advices matchadd() doesn't uses 'magic', 'smartcase' and 'ignorecase' options, however, search() uses them. This difference may result in the Jump to Highlights feature jump to a wrong word (e.g., when 'ignorecase' on), which is not highlighted.

[azabiong]

Oh! thanks for the good points! 👍 I'll test and update it right away.

[JS-Zheng]

IMHO, you can disable ignorecase temporarily, for example:

" save ignorecase value
try
    " disable ignorecase
    " do something
catch
    " do something
finally
    " restore ignorecase
endtry

Hope it helps 😉

[azabiong]

Thank you so much! 😄

[azabiong]

Alternatively, it seems straightforward to pass the case-sensitive option '\C' with the pattern to the search() function, like search('\C' . pattern). Now v1.50.2 supports this, thank you! 😄

[JS-Zheng]

It's a better and concise solution, good job! 😆