Add setting for minimum string length to trigger auto popup (#135)

* Add setting for minimum string length to trigger auto popup

* Use ternary

* Use simplified function

* Fix bug in new return function

* Add documentation for min_chars

* Add buffer override for min_chars

autoload/asyncomplete.vim

@@ -259,6 +259,14 @@ function! asyncomplete#cancel_popup() abort
   return pumvisible() ? "\<C-e>" : ''
 endfunction
 
+function! s:get_min_chars(source_name) abort
+  if exists('b:asyncomplete_min_chars')
+    return b:asyncomplete_min_chars
+  else
+    return get(s:sources[a:source_name], 'min_chars', g:asyncomplete_min_chars)
+  endif
+endfunction
+
 function! s:on_change() abort
     if s:should_skip() | return | endif
 
@@ -288,11 +296,12 @@ function! s:on_change() abort
     let l:refresh_pattern = get(b:, 'asyncomplete_refresh_pattern', '\(\k\+$\)')
     let [l:_, l:startidx, l:endidx] = asyncomplete#utils#matchstrpos(l:ctx['typed'], l:refresh_pattern)
     let l:startcol = l:startidx + 1
+    let l:typed_len = l:endidx - l:startidx
 
     if l:startidx > -1
         if s:should_skip_popup() | return | endif
         for l:source_name in b:asyncomplete_active_sources
-            if !has_key(l:sources_to_notify, l:source_name)
+            if l:typed_len >= s:get_min_chars(l:source_name) && !has_key(l:sources_to_notify, l:source_name)
                 if has_key(s:matches, l:source_name) && s:matches[l:source_name]['ctx']['lnum'] ==# l:ctx['lnum'] && s:matches[l:source_name]['startcol'] ==# l:startcol
                     continue
                 endif

doc/asyncomplete.txt

@@ -87,6 +87,14 @@ g:asyncomplete_preprocessor                        *g:asyncomplete_preprocessor*
 
     context and matches in arguments in preprecessor function should be treated
     as immutable.
+
+g:asyncomplete_min_chars                             *g:asyncomplete_min_chars*
+
+    Type: |Number|
+    Default: 1
+
+    Minimum consecutive characters to trigger auto-popup. Overridden by buffer
+    variable if set (`b:asyncomplete_min_chars`)
 ===============================================================================
 3. Functions                                            *asyncomplete-functions*
 

plugin/asyncomplete.vim

@@ -13,6 +13,7 @@ endif
 let g:asyncomplete_manager = get(g:, 'asyncomplete_manager', 'asyncomplete#managers#vim#init')
 let g:asyncomplete_change_manager = get(g:, 'asyncomplete_change_manager', ['asyncomplete#utils#_on_change#textchangedp#init', 'asyncomplete#utils#_on_change#timer#init'])
 let g:asyncomplete_triggers = get(g:, 'asyncomplete_triggers', {'*': ['.', '>', ':'] })
+let g:asyncomplete_min_chars = get(g:, 'asyncomplete_min_chars', 1)
 
 let g:asyncomplete_auto_completeopt = get(g:, 'asyncomplete_auto_completeopt', 1)
 let g:asyncomplete_auto_popup = get(g:, 'asyncomplete_auto_popup', 1)