diff --git a/autoload/lightline.vim b/autoload/lightline.vim
index 463f148..44d0671 100644
--- a/autoload/lightline.vim
+++ b/autoload/lightline.vim
@@ -2,7 +2,7 @@
 " Filename: autoload/lightline.vim
 " Author: itchyny
 " License: MIT License
-" Last Change: 2016/03/21 16:05:22.
+" Last Change: 2016/03/21 16:28:31.
 " =============================================================================
 
 let s:save_cpo = &cpo
diff --git a/test/expand.vim b/test/expand.vim
index 20d0542..84b2e8e 100644
--- a/test/expand.vim
+++ b/test/expand.vim
@@ -119,6 +119,58 @@ function! s:suite.custom_type_number()
   delfunction Custom
 endfunction
 
+function! s:suite.custom_void_string_array()
+  function! Custom()
+    return ['', '', '']
+  endfunction
+  let g:lightline = { 'component_expand': { 'custom': 'Custom' } }
+  call lightline#init()
+  call s:assert.equals(SID('expand')([['readonly', 'filename'], ['custom'], ['modified']]),
+        \ [[['readonly', 'filename'], ['modified']], [[0, 0], [0]], [0, 2, 3]])
+  call s:assert.equals(SID('expand')([['readonly', 'filename', 'custom', 'modified']]),
+        \ [[['readonly', 'filename', 'modified']], [[0, 0, 0]], [0, 1]])
+  delfunction Custom
+endfunction
+
+function! s:suite.custom_type_void_string_array()
+  function! Custom()
+    return ['', '', '']
+  endfunction
+  let g:lightline = { 'component_expand': { 'custom': 'Custom' }, 'component_type': { 'custom': 'custom' } }
+  call lightline#init()
+  call s:assert.equals(SID('expand')([['readonly', 'filename'], ['custom'], ['modified']]),
+        \ [[['readonly', 'filename'], ['modified']], [[0, 0], [0]], [0, 2, 3]])
+  call s:assert.equals(SID('expand')([['readonly', 'filename', 'custom', 'modified']]),
+        \ [[['readonly', 'filename', 'modified']], [[0, 0, 0]], [0, 1]])
+  delfunction Custom
+endfunction
+
+function! s:suite.custom_void_string_array_2()
+  function! Custom()
+    return ['', 'custom', '']
+  endfunction
+  let g:lightline = { 'component_expand': { 'custom': 'Custom' } }
+  call lightline#init()
+  call s:assert.equals(SID('expand')([['readonly', 'filename'], ['custom'], ['modified']]),
+        \ [[['readonly', 'filename'], ['custom'], ['modified']], [[0, 0], [1], [0]], [0, 1, 2, 3]])
+  call s:assert.equals(SID('expand')([['readonly', 'filename', 'custom', 'modified']]),
+        \ [[['readonly', 'filename', 'custom', 'modified']], [[0, 0, 1, 0]], [0, 1]])
+  delfunction Custom
+endfunction
+
+function! s:suite.custom_type_void_string_array_2()
+  function! Custom()
+    return ['', 'custom', '']
+  endfunction
+  let g:lightline = { 'component_expand': { 'custom': 'Custom' }, 'component_type': { 'custom': 'custom' } }
+  call lightline#init()
+  call s:assert.equals(SID('expand')([['readonly', 'filename'], ['custom'], ['modified']]),
+        \ [[['readonly', 'filename'], ['custom'], ['modified']], [[0, 0], [1], [0]], [0, 'custom', 2, 3]])
+  call s:assert.equals(SID('expand')([['readonly', 'filename', 'custom', 'modified']]),
+        \ [[['readonly', 'filename'], ['custom'], ['modified']], [[0, 0], [1], [0]], [0, 'custom', 0, 1]])
+  delfunction Custom
+endfunction
+
 function! s:suite.custom_mixed()
   function! Custom()
     return ['left', { 'custom': 24 }, [function('tr')]]