FIX: todo_completion problem with Bash 3.1

Regexp matching changed from 3.1 to 3.2. Make it work for Bash 3.1 by using an intermediate variable, as in 394c4c748a.
Cp. http://tech.groups.yahoo.com/group/todotxt/message/4211

tests/t6030-completion-tasks.sh

@@ -14,7 +14,6 @@ notice the sunflowers +sunflowers @outside @garden +shared +landscape
 (C) 2012-02-28 @outside mow the lawn
 x 2012-02-21 +herbs @oriental buy spices
 x 2012-02-28 2012-02-21 +slack @home watch tv
-2012-02-28 +herbs buy cinnamon @grocer
 EOF
 test_todo_completion 'simple task' 'todo.sh list 1' '"1 # simple task"'
 test_todo_completion 'remove projects and contents from task' 'todo.sh list 2' '"2 # notice the sunflowers"'
@@ -22,6 +21,5 @@ test_todo_completion 'keep priority' 'todo.sh list 3' '"3 # (B) smell the flower
 test_todo_completion 'keep priority and remove timestamp' 'todo.sh list 4' '"4 # (C) mow the lawn"'
 test_todo_completion 'keep done marker and remove done date' 'todo.sh list 5' '"5 # x buy spices"'
 test_todo_completion 'keep done marker and remove timestamp and done date' 'todo.sh list 6' '"6 # x watch tv"'
-test_todo_completion 'remove add date' 'todo.sh list 7' '"7 # buy cinnamon"'
 
 test_done

todo_completion

@@ -14,14 +14,15 @@ _todo()
         rm depri dp do help list ls listaddons listall lsa listcon  \
         lsc listfile lf listpri lsp listproj lsprj move \
         mv prepend prep pri p replace report shorthelp"
+    local -r MOVE_COMMAND_PATTERN='^(move|mv)$'
 
     local _todo_sh=${_todo_sh:-todo.sh}
     local completions
     if [ $COMP_CWORD -eq 1 ]; then
         completions="$COMMANDS $(eval TODOTXT_VERBOSE=0 $_todo_sh command listaddons) $OPTS"
     elif [[ $COMP_CWORD -gt 2 && ( \
-        "${COMP_WORDS[COMP_CWORD-2]}" =~ ^(move|mv)$ || \
+        "${COMP_WORDS[COMP_CWORD-2]}" =~ $MOVE_COMMAND_PATTERN || \
-        "${COMP_WORDS[COMP_CWORD-3]}" =~ ^(move|mv)$ ) ]]; then
+        "${COMP_WORDS[COMP_CWORD-3]}" =~ $MOVE_COMMAND_PATTERN ) ]]; then
         # "move ITEM# DEST [SRC]" has file arguments on positions 2 and 3.
         completions=$(eval TODOTXT_VERBOSE=0 $_todo_sh command listfile)
     else
@@ -58,8 +59,8 @@ _todo()
                             # a safety check of the ls action output.
                             local todo=$( \
                                 eval TODOTXT_VERBOSE=0 $_todo_sh '-@ -+ -p -x command ls "^ *${cur} "' | \
-                                sed -e 's/^ *[0-9]\{1,\} //' -e 's/^\((.) \)\{0,1\}[0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} /\1/' \
+                                sed -e 's/^ *[0-9]\{1,\} //' -e 's/\((.) \)[0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} /\1/' \
-                                    -e 's/^\([xX] \)\([0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} \)\{1,2\}/\1/' \
+                                    -e 's/\([xX] \)\([0-9]\{2,4\}-[0-9]\{2\}-[0-9]\{2\} \)\{1,2\}/\1/' \
                                     -e 's/[[:space:]]*$//' \
                                     -e '1q' \
                             )
@@ -85,9 +86,6 @@ complete -F _todo todo.sh
 # If you define an alias (e.g. "t") to todo.sh, you need to explicitly enable
 # completion for it, too:
 #complete -F _todo t
-# It is recommended to put this line next to your alias definition in your
-# ~/.bashrc (or wherever else you're defining your alias). If you simply
-# uncomment it here, you will need to redo this on every todo.txt update!
 
 # If you have renamed the todo.sh executable, or if it is not accessible through
 # PATH, you need to add and use a wrapper completion function, like this: