(testsuite) Check for grep and ls invoked without "command", see README

test/runLint

@@ -2,7 +2,7 @@
 
 gitgrep()
 {
-    local out=$(git grep -I -E -n "$1" | \
+    local out=$(git grep -I -P -n "$1" | \
         grep -E '^(bash_completion|completions/|test/)' | \
         grep -Fv 'test/runLint')
     if [ -n "$out" ] ; then
@@ -40,3 +40,6 @@ gitgrep $cmdstart'[ef]grep\b' \
 
 # TODO: $ in sed subexpression used as an anchor (POSIX BRE optional, not in
 #       Solaris/FreeBSD)
+
+gitgrep '(?<!command)'$cmdstart'(grep|ls)(\s|$)' \
+    'invoke grep and ls with "command" prefix, e.g. "command grep"'