Add crypt indicator

If editing an encrypted file, add an indicator, that the file is
encrypted

autoload/airline.vim

@@ -161,6 +161,10 @@ function! airline#check_mode(winnr)
     call add(l:mode, 'paste')
   endif
 
+  if g:airline_detect_crypt && !empty(&key)
+    call add(l:mode, 'crypt')
+  endif
+
   if &readonly || ! &modifiable
     call add(l:mode, 'readonly')
   endif

autoload/airline/init.vim

@@ -15,13 +15,13 @@ function! airline#init#bootstrap()
   let s:loaded = 1
 
   let g:airline#init#bootstrapping = 1
-
   call s:check_defined('g:airline_left_sep', get(g:, 'airline_powerline_fonts', 0)?"\ue0b0":">")
   call s:check_defined('g:airline_left_alt_sep', get(g:, 'airline_powerline_fonts', 0)?"\ue0b1":">")
   call s:check_defined('g:airline_right_sep', get(g:, 'airline_powerline_fonts', 0)?"\ue0b2":"<")
   call s:check_defined('g:airline_right_alt_sep', get(g:, 'airline_powerline_fonts', 0)?"\ue0b3":"<")
   call s:check_defined('g:airline_detect_modified', 1)
   call s:check_defined('g:airline_detect_paste', 1)
+  call s:check_defined('g:airline_detect_crypt', 1)
   call s:check_defined('g:airline_detect_iminsert', 0)
   call s:check_defined('g:airline_inactive_collapse', 1)
   call s:check_defined('g:airline_exclude_filenames', ['DebuggerWatch','DebuggerStack','DebuggerStatus'])
@@ -55,6 +55,9 @@ function! airline#init#bootstrap()
         \ }, 'keep')
 
   call s:check_defined('g:airline_symbols', {})
+  let s:airline_crypt=''
+  " generate crypt symbol, "\u" only accepts up to 4 chars
+  exe 'sil norm!' ":\<C-V>U1F512\<c-\>eextend(s:, {'airline_crypt': getcmdline()}).airline_crypt\n"
   call extend(g:airline_symbols, {
         \ 'paste': get(g:, 'airline_paste_symbol', 'PASTE'),
         \ 'readonly': get(g:, 'airline_readonly_symbol', get(g:, 'airline_powerline_fonts', 0) ? "\ue0a2" : 'RO'),
@@ -63,7 +66,9 @@ function! airline#init#bootstrap()
         \ 'branch': get(g:, 'airline_branch_prefix', get(g:, 'airline_powerline_fonts', 0) ? "\ue0a0" : ''),
         \ 'modified': '+',
         \ 'space': ' ',
+        \ 'crypt': get(g:, 'airline_crypt_symbol', s:airline_crypt),
         \ }, 'keep')
+  unlet! s:airline_crypt
 
   call airline#parts#define('mode', {
         \ 'function': 'airline#parts#mode',
@@ -71,6 +76,7 @@ function! airline#init#bootstrap()
         \ })
   call airline#parts#define_function('iminsert', 'airline#parts#iminsert')
   call airline#parts#define_function('paste', 'airline#parts#paste')
+  call airline#parts#define_function('crypt', 'airline#parts#crypt')
   call airline#parts#define_function('filetype', 'airline#parts#filetype')
   call airline#parts#define('readonly', {
         \ 'function': 'airline#parts#readonly',
@@ -88,7 +94,7 @@ endfunction
 function! airline#init#sections()
   let spc = g:airline_symbols.space
   if !exists('g:airline_section_a')
-    let g:airline_section_a = airline#section#create_left(['mode', 'paste', 'capslock', 'iminsert'])
+    let g:airline_section_a = airline#section#create_left(['mode', 'crypt', 'paste', 'capslock', 'iminsert'])
   endif
   if !exists('g:airline_section_b')
     let g:airline_section_b = airline#section#create(['hunks', 'branch'])

autoload/airline/parts.vim

@@ -54,6 +54,10 @@ function! airline#parts#mode()
   return get(w:, 'airline_current_mode', '')
 endfunction
 
+function! airline#parts#crypt()
+  return g:airline_detect_crypt && !empty(&key) ? g:airline_symbols.crypt : ''
+endfunction
+
 function! airline#parts#paste()
   return g:airline_detect_paste && &paste ? g:airline_symbols.paste : ''
 endfunction

doc/airline.txt

@@ -70,6 +70,9 @@ values):
 * enable paste detection >
   let g:airline_detect_paste=1
 <
+* enable crypt detection >
+  let g:airline_detect_crypt=1
+<
 * enable iminsert detection >
   let g:airline_detect_iminsert=0
 <
@@ -176,6 +179,7 @@ its contents. >
   let g:airline_left_sep = '▶'
   let g:airline_right_sep = '«'
   let g:airline_right_sep = '◀'
+  let g:airline_symbols.crypt = '🔒'
   let g:airline_symbols.linenr = '␊'
   let g:airline_symbols.linenr = '␤'
   let g:airline_symbols.linenr = '¶'
@@ -214,7 +218,7 @@ section.
 >
   variable names                default contents
   ----------------------------------------------------------------------------
-  let g:airline_section_a       (mode, paste, iminsert)
+  let g:airline_section_a       (mode, crypt, paste, iminsert)
   let g:airline_section_b       (hunks, branch)
   let g:airline_section_c       (bufferline or filename)
   let g:airline_section_gutter  (readonly, csv)
@@ -639,6 +643,7 @@ Before is a list of parts that are predefined by vim-airline.
 * `mode`           displays the current mode
 * `iminsert`       displays the current insert method
 * `paste`          displays the paste indicator
+* crypt          displays the crypted indicator
 * `filetype`       displays the file type
 * `readonly`       displays the read only indicator
 * `file`           displays the filename and modified indicator