Define a new behavior of 'skip_space' option when it is 2.

autoload/operator/sandwich.vim

@@ -737,7 +737,7 @@ function! s:search(recipes) dict abort "{{{
       if i == 1 || opt.integrated.skip_space
         let head_c = s:get_cursorchar(head)
         let tail_c = s:get_cursorchar(tail)
-        if head_c ==# tail_c
+        if head_c ==# tail_c && !(opt.integrated.skip_space == 2 && head_c =~# '\s')
           let target = {
                 \   'head1': head, 'tail1': head,
                 \   'head2': tail, 'tail2': tail,
@@ -2305,7 +2305,7 @@ let s:default_opt.delete.line = {
       \   'cursor'    : 'inner_head',
       \   'noremap'   : 1,
       \   'regex'     : 0,
-      \   'skip_space': 1,
+      \   'skip_space': 2,
       \   'skip_char' : 0,
       \   'highlight' : 1,
       \   'command'   : [],
@@ -2344,7 +2344,7 @@ let s:default_opt.replace.line = {
       \   'regex'     : 0,
       \   'expr'      : 0,
       \   'noremap'   : 1,
-      \   'skip_space': 1,
+      \   'skip_space': 2,
       \   'skip_char' : 0,
       \   'highlight' : 1,
       \   'command'   : [],

doc/operator-sandwich.jax

@@ -862,8 +862,8 @@ highlight
 
 
 skip_space
-	値が真なら、指定された文字列の両端がスペースであった場合にこれらをスキ
-	ップします。
+	値が 1 なら、指定された文字列の両端がスペースであった場合にこれらをス
+	キップします。
 >
 	let g:sandwich#recipes += [
 	  \   {'buns': ['(', ')'], 'skip_space': 0}
@@ -887,6 +887,7 @@ skip_space
 	" Press sda"
 	"   ?"foo"   --->  ?foo    : ? is space
 <
+	両端が空白の場合にもこれをスキップするためには値を 2 にします。
 
 	デフォルト値
 	  * add
@@ -895,11 +896,11 @@ skip_space
 	    - block: 1
 	  * delete
 	    - char : 1
-	    - line : 1
+	    - line : 2
 	    - block: 1
 	  * replace
 	    - char : 1
-	    - line : 1
+	    - line : 2
 	    - block: 1
 
 

doc/operator-sandwich.txt

@@ -870,7 +870,7 @@ highlight
 
 skip_space
 	This option enables to skip spaces at both ends of a assigned region.
-	If the value is true, adjust the both ends to skip white spaces.
+	If the value is 1, adjust the both ends to skip white spaces.
 >
 	let g:sandwich#recipes += [
 	  \   {'buns': ['(', ')'], 'skip_space': 0}
@@ -895,6 +895,8 @@ skip_space
 	" Press sda"
 	"   ?"foo"   --->  ?foo    : ? is space
 <
+	If the value is 2, adjust the both ends to skip white spaces even
+	though the both ends are white spaces.
 
 	Default values
 	  * add
@@ -902,13 +904,13 @@ skip_space
 	    - line : 1
 	    - block: 1
 	  * delete
-	    - char : 1
-	    - line : 1
-	    - block: 1
+	    - char : 2
+	    - line : 2
+	    - block: 2
 	  * replace
-	    - char : 1
-	    - line : 1
-	    - block: 1
+	    - char : 2
+	    - line : 2
+	    - block: 2