Replace backticks in config with $(...)

This applies e24777fa2c to todo.cfg, too, and adds a verification to the existing test.

Note: Because todo.cfg is preprocessed by test-lib, we use the original config from the working copy, not the copy inside the test fixture.

tests/t0100-code-nobacktick.sh

@@ -9,8 +9,15 @@ On failure, it will print each offending line number and line.
 '
 . ./test-lib.sh
 
+backtick_check()
+{
+    sed -n -e 's/\(^\|[ \t]\)#.*//' -e '/`/{' -e '=;p' -e '}' "$@"
+}
+
 test_todo_session 'no old-style backtick command substitution' <<EOF
->>> sed -n -e 's/\(^\|[ \t]\)#.*//' -e '/\`/{' -e '=;p' -e '}' "$(which todo.sh)"
+>>> backtick_check bin/todo.sh
+
+>>> backtick_check ../../todo.cfg
 EOF
 
 test_done

todo.cfg

@@ -2,7 +2,7 @@
 
 # Your todo.txt directory
 #export TODO_DIR="/Users/gina/Documents/todo"
-export TODO_DIR=`dirname "$0"`
+export TODO_DIR=$(dirname "$0")
 
 # Your todo/done/report.txt locations
 export TODO_FILE="$TODO_DIR/todo.txt"

todo.sh

@@ -1105,7 +1105,7 @@ case $action in
     TOTAL=$( sed -n '$ =' "$TODO_FILE" )
     PADDING=${#TOTAL}
 
-    post_filter_command="${post_filter_command:-}${post_filter_command:+ | }awk -v TOTAL=$TOTAL -v PADDING=$PADDING '{ \$1 = sprintf(\"%\" PADDING \"d\", (\$1 > TOTAL ? 0 : \$1)); print }' "
+    post_filter_command="awk -v TOTAL=$TOTAL -v PADDING=$PADDING '{ \$1 = sprintf(\"%\" PADDING \"d\", (\$1 > TOTAL ? 0 : \$1)); print }' "
     cat "$TODO_FILE" "$DONE_FILE" | TODOTXT_VERBOSE=0 _format '' "$PADDING" "$@"
 
     if [ $TODOTXT_VERBOSE -gt 0 ]; then
@@ -1149,7 +1149,7 @@ case $action in
     shift ## was "listpri", new $1 is priority to list or first TERM
 
     pri=$(printf "%s\n" "$1" | tr 'a-z' 'A-Z' | grep -e '^[A-Z]$' -e '^[A-Z]-[A-Z]$') && shift || pri="A-Z"
-    post_filter_command="${post_filter_command:-}${post_filter_command:+ | }grep '^ *[0-9]\+ ([${pri}]) '"
+    post_filter_command="grep '^ *[0-9]\+ ([${pri}]) '"
     _list "$TODO_FILE" "$@"
     ;;