Fixes when ran by "bash shellcpec" and "ksh shellspec"

shellspec

@@ -105,7 +105,11 @@ readlinkf() {
   done 2>/dev/null; cd "$2" && OLDPWD=$3 && [ ${5+x} ] && printf '%s\n' "$5"
 }
 
-if ! SHELLSPEC_PATH=$(readlinkf "$0"); then
+self=$0
+[ "${BASH_SOURCE:-}" ] && eval "self=\${BASH_SOURCE[0]}"
+( eval "[ \"\${.sh.file:-}\" ]" ) 2>/dev/null && eval "self=\${.sh.file}"
+
+if ! SHELLSPEC_PATH=$(readlinkf "$self"); then
  echo "Failed to detect shellspec real path." >&2
  exit 1
 fi

spec/libexec/shellspec_spec.sh

@@ -164,7 +164,7 @@ Describe "libexec/shellspec.sh"
     End
 
     Context "when ps command not found"
-      Before PATH=''
+      ps() { exit 127; }
       It "returns nothing"
         When call read_ps 111
         The status should be success