syntax/parse: reverted error message, fixed error test

collects/syntax/private/stxparse/runtime.rkt

@@ -615,7 +615,7 @@ An Expectation is one of
 ;; FIXME: change to normal 'error', if src gets stripped away
 (define (check-literal id phase ctx)
   (unless (identifier-binding id phase)
-    (raise-syntax-error #f "literal identifier has no binding" ctx id)))
+    (raise-syntax-error #f "unbound identifier not allowed as literal" ctx id)))
 
 ;; free-identifier=?/phases : id phase-level id phase-level -> boolean
 ;; Determines whether x has the same binding at phase-level phase-x

collects/syntax/private/stxparse/sc.rkt

@@ -163,7 +163,7 @@
                (begin-for-syntax/once
                 (for ([x (syntax->list #'(external ...))])
                   (unless (identifier-binding x 0)
-                    (raise-syntax-error #f "literal identifier has no binding"
+                    (raise-syntax-error #f "unbound identifier not allowed as literal"
                                         (quote-syntax #,stx) x))))))))]))
 
 #|

collects/tests/stxparse/more-tests.rkt

@@ -93,11 +93,20 @@
        #rx"^define-syntax-class: "
        #rx"expected syntax-class variant")
 
+;(tcerr "check-literals-bound: unbound literal"
+;       (let () (define-syntax-class x #:literals (foo) (pattern (foo))) 0)
+;       #rx"^define-syntax-class: "
+;       #rx"unbound identifier not allowed as literal")
+
 (tcerr "check-literals-bound: unbound literal"
-       (let () (define-syntax-class x #:literals (foo) (pattern (foo))) 0)
-       #rx"^define-syntax-class: "
+       (let () (define-literal-set x (foo)) 0)
+       #rx"^define-literal-set: "
        #rx"unbound identifier not allowed as literal")
 
+(tcerr "check-literals-bound: unbound literal"
+       (syntax-parse #'x #:literals (define defunky) [_ 'ok])
+       #rx"^syntax-parse: "
+       #rx"unbound identifier not allowed as literal")
 
 (tcerr "append-lits+litsets: duplicate"
        (let ()