disable for all repos by default about vim-gutentags

[ludovicchabant]

Why do you want Gutentags to generate tags only for a few repos? Is it because most of the repos are too big, or don't contain code, or something?

[goweol]

I don't need to use tag for many GIT repo. It is best to me, if gutentags is only enabled if 'tags' (or some given filename) file is found. Then, If I want to use tag, I will generate basic tags file. Then, gutentags will automatically updated it if I do some work.

[ludovicchabant]

Can you try this quick patch?

diff --git a/autoload/gutentags.vim b/autoload/gutentags.vim
--- a/autoload/gutentags.vim
+++ b/autoload/gutentags.vim
@@ -107,6 +107,12 @@
         return
     endif

+    " Let the user specify custom ways to disable Gutentags.
+    if g:gutentags_enabled_user_func != '' &&
+                \!call(g:gutentags_enabled_user_func, expand('%:p'))
+        return
+    endif
+
     " Try and find what tags file we should manage.
     call gutentags#trace("Scanning buffer '" . bufname('%') . "' for gutentags setup...")
     try
diff --git a/plugin/gutentags.vim b/plugin/gutentags.vim
--- a/plugin/gutentags.vim
+++ b/plugin/gutentags.vim
@@ -41,6 +41,10 @@
     let g:gutentags_enabled = 1
 endif

+if !exists('g:gutentags_enabled_user_func')
+    let g:gutentags_enabled_user_func = ''
+endif
+
 if !exists('g:gutentags_modules')
     let g:gutentags_modules = ['ctags']
 endif

It lets you specify the name of a function in g:gutentags_enabled_user_func. This function will get called with the path to each new buffer, and if it returns 0 (or some other false value), Gutentags will be disable for that buffer. You could make that function compare the given path to a list of white-listed repos, or check for the existence of a tags file, or something.

[goweol]

I tried with a simple func:

func! GutenTagsGenCheck(file)
  "call gutentags#trace(gutentags#get_project_root(a:file))
  return 0
endfunc
let g:gutentags_enabled_user_func = 'GutenTagsGenCheck'

And I've got an error:

Error detected while processing function gutentags#setup_gutentags:
line 14:
E714: List required

Thanks

[ludovicchabant]

Woops sorry, typo in the code calling your custom function. Put square brackets around the second parameter:

      \!call(g:gutentags_enabled_user_func, [expand('%:p')])

[goweol]

Now it worked fine as I expected.

    func! MyGutentagsFunc(file)
      let tag_file = gutentags#get_project_root(a:file).'/tags'
      return filereadable(tag_file)
    endfunc
    let g:gutentags_enabled_user_func = 'MyGutentagsFunc'

Thanks!

[goweol]

With old MyGutentagsFunc(), I saw an error message when I run 'vim' without filename.

Error detected while processing function gutentags#setup_gutentags[14]..MyGutent
agsFunc[1]..gutentags#get_project_root[17]..gutentags#throw:
line    2:
E605: Exception not caught: gutentags: Can't figure out what tag file to use for
: 

So that, I changed it like below. Does it correct? Is there any other way?

    func! MyGutentagsFunc(file)
      try
        let tag_file = gutentags#get_project_root(a:file).'/tags'
        return filereadable(tag_file)
      catch
        return 0
      endtry
    endfunc

[ludovicchabant]

Ok I submitted the patch (see a844f08).

A try...catch is probably a good idea, but when I run vim with no arguments the callback doesn't get called for me (because the default buffer is not a writable file). Maybe you have Vim setup to open something by default?