guile/test-suite/tests/syntax.test

;;;; syntax.test --- test suite for Guile's syntactic forms    -*- scheme -*-
;;;;
;;;; Copyright (C) 2001, 2003, 2004, 2005, 2006, 2009, 2010,
;;;;   2011, 2012, 2013, 2014 Free Software Foundation, Inc.
;;;;
;;;; This library is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Lesser General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 3 of the License, or (at your option) any later version.
;;;; 
;;;; This library is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;;;; Lesser General Public License for more details.
;;;; 
;;;; You should have received a copy of the GNU Lesser General Public
;;;; License along with this library; if not, write to the Free Software
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

(define-module (test-suite test-syntax)
  #:use-module (ice-9 regex)
  #:use-module (ice-9 local-eval)
  #:use-module (test-suite lib))


(define exception:generic-syncase-error
  "source expression failed to match")
(define exception:unexpected-syntax
  "unexpected syntax")

(define exception:bad-expression
  "Bad expression")

(define exception:missing/extra-expr
  "Missing or extra expression")
(define exception:missing-expr
  "Missing expression")
(define exception:missing-body-expr
  "no expressions in body")
(define exception:extra-expr
  "Extra expression")
(define exception:illegal-empty-combination
  "Illegal empty combination")

(define exception:bad-lambda
  "bad lambda")
(define exception:bad-let
  "bad let$")
(define exception:bad-letrec
  "bad letrec$")
(define exception:bad-letrec*
  "bad letrec\\*$")
(define exception:bad-set!
  "bad set!")
(define exception:bad-quote
  '(quote . "bad syntax"))
(define exception:bad-bindings
  "Bad bindings")
(define exception:bad-binding
  "Bad binding")
(define exception:duplicate-binding
  "duplicate bound variable")
(define exception:bad-body
  "^bad body")
(define exception:bad-formals
  "invalid argument list")
(define exception:bad-formal
  "Bad formal")
(define exception:duplicate-formals
  "duplicate identifier in argument list")

(define exception:missing-clauses
  "Missing clauses")
(define exception:misplaced-else-clause
  "Misplaced else clause")
(define exception:bad-case-clause
  "Bad case clause")
(define exception:bad-case-labels
  "Bad case labels")
(define exception:bad-cond-clause
  "Bad cond clause")

(define exception:too-many-args
  "too many arguments")
(define exception:zero-expression-sequence
  "sequence of zero expressions")

(define exception:define-values-wrong-number-of-return-values
  (cons 'wrong-number-of-args "^define-values: wrong number of return values returned by expression"))


;; (put 'pass-if-syntax-error 'scheme-indent-function 1)
(define-syntax pass-if-syntax-error
  (syntax-rules ()
    ((_ name pat exp)
     (pass-if name
       (catch 'syntax-error
         (lambda () exp (error "expected syntax-error exception"))
         (lambda (k who what where form . maybe-subform)
           (if (if (pair? pat)
                   (and (eq? who (car pat))
                        (string-match (cdr pat) what))
                   (string-match pat what))
               #t
               (error "unexpected syntax-error exception" what pat))))))))

(with-test-prefix "expressions"

  (with-test-prefix "Bad argument list"

    (pass-if-syntax-error "improper argument list of length 1"
      exception:generic-syncase-error
      (eval '(let ((foo (lambda (x y) #t)))
	       (foo . 1))
	    (interaction-environment)))

    (pass-if-syntax-error "improper argument list of length 2"
      exception:generic-syncase-error
      (eval '(let ((foo (lambda (x y) #t)))
	       (foo 1 . 2))
	    (interaction-environment))))

  (with-test-prefix "missing or extra expression"

    ;; R5RS says:
    ;; *Note:* In many dialects of Lisp, the empty combination, (),
    ;; is a legitimate expression.  In Scheme, combinations must
    ;; have at least one subexpression, so () is not a syntactically
    ;; valid expression.

    ;; Fixed on 2001-3-3
    (pass-if-syntax-error "empty parentheses \"()\""
      exception:unexpected-syntax
      (eval '()
	    (interaction-environment)))))

(with-test-prefix "quote"
  #t)

(with-test-prefix "quasiquote"

  (with-test-prefix "unquote"

    (pass-if "repeated execution"
      (let ((foo (let ((i 0)) (lambda () (set! i (+ i 1)) `(,i)))))
	(and (equal? (foo) '(1)) (equal? (foo) '(2))))))

  (with-test-prefix "unquote-splicing"

    (pass-if "extra arguments"
      (equal? (eval '(quasiquote ((unquote-splicing (list 1 2) (list 3 4))))
                    (interaction-environment))
              '(1 2 3 4)))))

(with-test-prefix "begin"

  (pass-if "valid (begin)"
    (eval '(begin (begin) #t) (interaction-environment)))

  (if (not (include-deprecated-features))
      (pass-if-syntax-error "invalid (begin)"
        exception:zero-expression-sequence
        (eval '(begin (if #t (begin)) #t) (interaction-environment)))))

(define-syntax matches?
  (syntax-rules (<>)
    ((_ (op arg ...) pat)   (let ((x (op arg ...)))
                              (matches? x pat)))
    ((_ x ())               (null? x))
    ((_ x (a . b))          (and (pair? x)
                                 (matches? (car x) a)
                                 (matches? (cdr x) b)))
    ((_ x <>)                #t) 
    ((_ x pat)              (equal? x 'pat))))

(with-test-prefix "lambda"

  (with-test-prefix "bad formals"

    (pass-if-syntax-error "(lambda)"
      exception:bad-lambda
      (eval '(lambda)
	    (interaction-environment)))

    (pass-if-syntax-error "(lambda . \"foo\")"
      exception:bad-lambda
      (eval '(lambda . "foo")
	    (interaction-environment)))

    (pass-if-syntax-error "(lambda \"foo\")"
      exception:bad-lambda
      (eval '(lambda "foo")
	    (interaction-environment)))

    (pass-if-syntax-error "(lambda \"foo\" #f)"
      exception:bad-formals
      (eval '(lambda "foo" #f)
	    (interaction-environment)))

    (pass-if-syntax-error "(lambda (x 1) 2)"
      exception:bad-formals
      (eval '(lambda (x 1) 2)
	    (interaction-environment)))

    (pass-if-syntax-error "(lambda (1 x) 2)"
      exception:bad-formals
      (eval '(lambda (1 x) 2)
	    (interaction-environment)))

    (pass-if-syntax-error "(lambda (x \"a\") 2)"
      exception:bad-formals
      (eval '(lambda (x "a") 2)
	    (interaction-environment)))

    (pass-if-syntax-error "(lambda (\"a\" x) 2)"
      exception:bad-formals
      (eval '(lambda ("a" x) 2)
	    (interaction-environment))))

  (with-test-prefix "duplicate formals"

    ;; Fixed on 2001-3-3
    (pass-if-syntax-error "(lambda (x x) 1)"
      exception:duplicate-formals
      (eval '(lambda (x x) 1)
	    (interaction-environment)))

    ;; Fixed on 2001-3-3
    (pass-if-syntax-error "(lambda (x x x) 1)"
      exception:duplicate-formals
      (eval '(lambda (x x x) 1)
	    (interaction-environment))))

  (with-test-prefix "bad body"

    (pass-if-syntax-error "(lambda ())"
      exception:bad-lambda
      (eval '(lambda ())
	    (interaction-environment)))))

(with-test-prefix "let"

  (with-test-prefix "bindings"

    (pass-if-exception "late binding"
      exception:unbound-var
      (let ((x 1) (y x)) y)))

  (with-test-prefix "bad bindings"

    (pass-if-syntax-error "(let)"
      exception:bad-let
      (eval '(let)
	    (interaction-environment)))

    (pass-if-syntax-error "(let 1)"
      exception:bad-let
      (eval '(let 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(let (x))"
      exception:bad-let
      (eval '(let (x))
	    (interaction-environment)))

    (pass-if-syntax-error "(let ((x)))"
      exception:bad-let
      (eval '(let ((x)))
	    (interaction-environment)))

    (pass-if-syntax-error "(let (x) 1)"
      exception:bad-let
      (eval '(let (x) 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(let ((x)) 3)"
      exception:bad-let
      (eval '(let ((x)) 3)
	    (interaction-environment)))

    (pass-if-syntax-error "(let ((x 1) y) x)"
      exception:bad-let
      (eval '(let ((x 1) y) x)
	    (interaction-environment)))

    (pass-if-syntax-error "(let ((1 2)) 3)"
      exception:bad-let
      (eval '(let ((1 2)) 3)
	    (interaction-environment))))

  (with-test-prefix "duplicate bindings"

    (pass-if-syntax-error "(let ((x 1) (x 2)) x)"
      exception:duplicate-binding
      (eval '(let ((x 1) (x 2)) x)
	    (interaction-environment))))

  (with-test-prefix "bad body"

    (pass-if-syntax-error "(let ())"
      exception:bad-let
      (eval '(let ())
	    (interaction-environment)))

    (pass-if-syntax-error "(let ((x 1)))"
      exception:bad-let
      (eval '(let ((x 1)))
	    (interaction-environment)))))

(with-test-prefix "named let"

  (with-test-prefix "initializers"

    (pass-if "evaluated in outer environment"
      (let ((f -))
	(eqv? (let f ((n (f 1))) n) -1))))

  (with-test-prefix "bad bindings"

    (pass-if-syntax-error "(let x (y))"
      exception:bad-let
      (eval '(let x (y))
	    (interaction-environment))))

  (with-test-prefix "bad body"

    (pass-if-syntax-error "(let x ())"
      exception:bad-let
      (eval '(let x ())
	    (interaction-environment)))

    (pass-if-syntax-error "(let x ((y 1)))"
      exception:bad-let
      (eval '(let x ((y 1)))
	    (interaction-environment)))))

(with-test-prefix "let*"

  (with-test-prefix "bindings"

    (pass-if "(let* ((x 1) (x 2)) ...)"
      (let* ((x 1) (x 2))
	(= x 2)))

    (pass-if "(let* ((x 1) (x x)) ...)"
      (let* ((x 1) (x x))
	(= x 1)))

    (pass-if "(let ((x 1) (y 2)) (let* () ...))"
      (let ((x 1) (y 2))
        (let* ()
          (and (= x 1) (= y 2))))))

  (with-test-prefix "bad bindings"

    (pass-if-syntax-error "(let*)"
      exception:generic-syncase-error
      (eval '(let*)
	    (interaction-environment)))

    (pass-if-syntax-error "(let* 1)"
      exception:generic-syncase-error
      (eval '(let* 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(let* (x))"
      exception:generic-syncase-error
      (eval '(let* (x))
	    (interaction-environment)))

    (pass-if-syntax-error "(let* (x) 1)"
      exception:generic-syncase-error
      (eval '(let* (x) 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(let* ((x)) 3)"
      exception:generic-syncase-error
      (eval '(let* ((x)) 3)
	    (interaction-environment)))

    (pass-if-syntax-error "(let* ((x 1) y) x)"
      exception:generic-syncase-error
      (eval '(let* ((x 1) y) x)
	    (interaction-environment)))

    (pass-if-syntax-error "(let* x ())"
      exception:generic-syncase-error
      (eval '(let* x ())
	    (interaction-environment)))

    (pass-if-syntax-error "(let* x (y))"
      exception:generic-syncase-error
      (eval '(let* x (y))
	    (interaction-environment)))

    (pass-if-syntax-error "(let* ((1 2)) 3)"
      exception:generic-syncase-error
      (eval '(let* ((1 2)) 3)
	    (interaction-environment))))

  (with-test-prefix "bad body"

    (pass-if-syntax-error "(let* ())"
      exception:generic-syncase-error
      (eval '(let* ())
	    (interaction-environment)))

    (pass-if-syntax-error "(let* ((x 1)))"
      exception:generic-syncase-error
      (eval '(let* ((x 1)))
	    (interaction-environment)))))

(with-test-prefix "letrec"

  (with-test-prefix "bindings"

    (pass-if-syntax-error "initial bindings are undefined"
      exception:used-before-defined
      (let ((x 1))
        ;; FIXME: the memoizer does initialize the var to undefined, but
        ;; the Scheme evaluator has no way of checking what's an
        ;; undefined value. Not sure how to do this.
        (throw 'unresolved)
	(letrec ((x 1) (y x)) y))))

  (with-test-prefix "bad bindings"

    (pass-if-syntax-error "(letrec)"
      exception:bad-letrec
      (eval '(letrec)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec 1)"
      exception:bad-letrec
      (eval '(letrec 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec (x))"
      exception:bad-letrec
      (eval '(letrec (x))
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec (x) 1)"
      exception:bad-letrec
      (eval '(letrec (x) 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec ((x)) 3)"
      exception:bad-letrec
      (eval '(letrec ((x)) 3)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec ((x 1) y) x)"
      exception:bad-letrec
      (eval '(letrec ((x 1) y) x)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec x ())"
      exception:bad-letrec
      (eval '(letrec x ())
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec x (y))"
      exception:bad-letrec
      (eval '(letrec x (y))
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec ((1 2)) 3)"
      exception:bad-letrec
      (eval '(letrec ((1 2)) 3)
	    (interaction-environment))))

  (with-test-prefix "duplicate bindings"

    (pass-if-syntax-error "(letrec ((x 1) (x 2)) x)"
      exception:duplicate-binding
      (eval '(letrec ((x 1) (x 2)) x)
	    (interaction-environment))))

  (with-test-prefix "bad body"

    (pass-if-syntax-error "(letrec ())"
      exception:bad-letrec
      (eval '(letrec ())
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec ((x 1)))"
      exception:bad-letrec
      (eval '(letrec ((x 1)))
	    (interaction-environment)))))

(with-test-prefix "letrec*"

  (with-test-prefix "bindings"

    (pass-if-syntax-error "initial bindings are undefined"
      exception:used-before-defined
      (begin
        ;; FIXME: the memoizer does initialize the var to undefined, but
        ;; the Scheme evaluator has no way of checking what's an
        ;; undefined value. Not sure how to do this.
        (throw 'unresolved)
	(letrec* ((x y) (y 1)) y))))

  (with-test-prefix "bad bindings"

    (pass-if-syntax-error "(letrec*)"
      exception:bad-letrec*
      (eval '(letrec*)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* 1)"
      exception:bad-letrec*
      (eval '(letrec* 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* (x))"
      exception:bad-letrec*
      (eval '(letrec* (x))
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* (x) 1)"
      exception:bad-letrec*
      (eval '(letrec* (x) 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* ((x)) 3)"
      exception:bad-letrec*
      (eval '(letrec* ((x)) 3)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* ((x 1) y) x)"
      exception:bad-letrec*
      (eval '(letrec* ((x 1) y) x)
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* x ())"
      exception:bad-letrec*
      (eval '(letrec* x ())
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* x (y))"
      exception:bad-letrec*
      (eval '(letrec* x (y))
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* ((1 2)) 3)"
      exception:bad-letrec*
      (eval '(letrec* ((1 2)) 3)
	    (interaction-environment))))

  (with-test-prefix "duplicate bindings"

    (pass-if-syntax-error "(letrec* ((x 1) (x 2)) x)"
      exception:duplicate-binding
      (eval '(letrec* ((x 1) (x 2)) x)
	    (interaction-environment))))

  (with-test-prefix "bad body"

    (pass-if-syntax-error "(letrec* ())"
      exception:bad-letrec*
      (eval '(letrec* ())
	    (interaction-environment)))

    (pass-if-syntax-error "(letrec* ((x 1)))"
      exception:bad-letrec*
      (eval '(letrec* ((x 1)))
	    (interaction-environment))))

  (with-test-prefix "referencing previous values"
    (pass-if (equal? (letrec ((a (cons 'foo 'bar))
                              (b a))
                       b)
                     '(foo . bar)))
    (pass-if (equal? (let ()
                       (define a (cons 'foo 'bar))
                       (define b a)
                       b)
                     '(foo . bar)))))

(with-test-prefix "if"

  (with-test-prefix "missing or extra expressions"

    (pass-if-syntax-error "(if)"
      exception:generic-syncase-error
      (eval '(if)
	    (interaction-environment)))

    (pass-if-syntax-error "(if 1 2 3 4)"
      exception:generic-syncase-error
      (eval '(if 1 2 3 4)
	    (interaction-environment)))))

(with-test-prefix "cond"

  (with-test-prefix "cond is hygienic"

    (pass-if "bound 'else is handled correctly"
      (eq? (let ((else 'ok)) (cond (else))) 'ok))

    (with-test-prefix "bound '=> is handled correctly"

      (pass-if "#t => 'ok"
        (let ((=> 'foo))
          (eq? (cond (#t => 'ok)) 'ok)))

      (pass-if "else =>"
        (let ((=> 'foo))
          (eq? (cond (else =>)) 'foo)))

      (pass-if "else => identity"
        (let ((=> 'foo))
          (eq? (cond (else => identity)) identity)))))

  (with-test-prefix "SRFI-61"

    (pass-if "always available"
      (cond-expand (srfi-61 #t) (else #f)))

    (pass-if "single value consequent"
      (eq? 'ok (cond (#t identity => (lambda (x) 'ok)) (else #f))))

    (pass-if "single value alternate"
      (eq? 'ok (cond (#t not => (lambda (x) #f)) (else 'ok))))

    (pass-if-exception "doesn't affect standard =>"
      exception:wrong-num-args
      (cond ((values 1 2) => (lambda (x y) #t))))

    (pass-if "multiple values consequent"
      (equal? '(2 1) (cond ((values 1 2)
			    (lambda (one two)
			      (and (= 1 one) (= 2 two))) =>
			    (lambda (one two) (list two one)))
			   (else #f))))

    (pass-if "multiple values alternate"
      (eq? 'ok (cond ((values 2 3 4)
		      (lambda args (equal? '(1 2 3) args)) =>
		      (lambda (x y z) #f))
		     (else 'ok))))

    (pass-if "zero values"
      (eq? 'ok (cond ((values) (lambda () #t) => (lambda () 'ok))
		     (else #f))))

    (pass-if "bound => is handled correctly"
      (let ((=> 'ok))
	(eq? 'ok (cond (#t identity =>) (else #f)))))

    (pass-if-syntax-error "missing recipient"
      '(cond . "wrong number of receiver expressions")
      (eval '(cond (#t identity =>))
            (interaction-environment)))

    (pass-if-syntax-error "extra recipient"
      '(cond . "wrong number of receiver expressions")
      (eval '(cond (#t identity => identity identity))
            (interaction-environment))))

  (with-test-prefix "bad or missing clauses"

    (pass-if-syntax-error "(cond)"
      exception:generic-syncase-error
      (eval '(cond)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond #t)"
      '(cond . "invalid clause")
      (eval '(cond #t)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond 1)"
      '(cond . "invalid clause")
      (eval '(cond 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond 1 2)"
      '(cond . "invalid clause")
      (eval '(cond 1 2)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond 1 2 3)"
      '(cond . "invalid clause")
      (eval '(cond 1 2 3)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond 1 2 3 4)"
      '(cond . "invalid clause")
      (eval '(cond 1 2 3 4)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond ())"
      '(cond . "invalid clause")
      (eval '(cond ())
	    (interaction-environment)))

    (pass-if-syntax-error "(cond () 1)"
      '(cond . "invalid clause")
      (eval '(cond () 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond (1) 1)"
      '(cond . "invalid clause")
      (eval '(cond (1) 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(cond (else #f) (#t #t))"
      '(cond . "else must be the last clause")
      (eval '(cond (else #f) (#t #t))
	    (interaction-environment))))

  (with-test-prefix "wrong number of arguments"

    (pass-if-exception "=> (lambda (x y) #t)"
      exception:wrong-num-args
      (cond (1 => (lambda (x y) #t))))))

(with-test-prefix "case"

  (pass-if "clause with empty labels list"
    (case 1 (() #f) (else #t)))

  (with-test-prefix "case handles '=> correctly"

    (pass-if "(1 2 3) => list"
      (equal? (case 1 ((1 2 3) => list))
              '(1)))

    (pass-if "else => list"
      (equal? (case 6
                ((1 2 3) 'wrong)
                (else => list))
              '(6)))

    (with-test-prefix "bound '=> is handled correctly"

      (pass-if "(1) => 'ok"
        (let ((=> 'foo))
          (eq? (case 1 ((1) => 'ok)) 'ok)))

      (pass-if "else =>"
        (let ((=> 'foo))
          (eq? (case 1 (else =>)) 'foo)))

      (pass-if "else => list"
        (let ((=> 'foo))
          (eq? (case 1 (else => identity)) identity))))

    (pass-if-syntax-error "missing recipient"
      '(case . "wrong number of receiver expressions")
      (eval '(case 1 ((1) =>))
            (interaction-environment)))

    (pass-if-syntax-error "extra recipient"
      '(case . "wrong number of receiver expressions")
      (eval '(case 1 ((1) => identity identity))
            (interaction-environment))))

  (with-test-prefix "case is hygienic"

    (pass-if-syntax-error "bound 'else is handled correctly"
      '(case . "invalid clause")
      (eval '(let ((else #f)) (case 1 (else #f)))
            (interaction-environment))))

  (with-test-prefix "bad or missing clauses"

    (pass-if-syntax-error "(case)"
      exception:generic-syncase-error
      (eval '(case)
	    (interaction-environment)))

    (pass-if-syntax-error "(case . \"foo\")"
      exception:generic-syncase-error
      (eval '(case . "foo")
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1)"
      exception:generic-syncase-error
      (eval '(case 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 . \"foo\")"
      exception:generic-syncase-error
      (eval '(case 1 . "foo")
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 \"foo\")"
      '(case . "invalid clause")
      (eval '(case 1 "foo")
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 ())"
      '(case . "invalid clause")
      (eval '(case 1 ())
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 (\"foo\"))"
      '(case . "invalid clause")
      (eval '(case 1 ("foo"))
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 (\"foo\" \"bar\"))"
      '(case . "invalid clause")
      (eval '(case 1 ("foo" "bar"))
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 ((2) \"bar\") . \"foo\")"
      exception:generic-syncase-error
      (eval '(case 1 ((2) "bar") . "foo")
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 ((2) \"bar\") (else))"
      '(case . "invalid clause")
      (eval '(case 1 ((2) "bar") (else))
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 (else #f) . \"foo\")"
      exception:generic-syncase-error
      (eval '(case 1 (else #f) . "foo")
	    (interaction-environment)))

    (pass-if-syntax-error "(case 1 (else #f) ((1) #t))"
      '(case . "else must be the last clause")
      (eval '(case 1 (else #f) ((1) #t))
	    (interaction-environment)))))

(with-test-prefix "top-level define"

  (pass-if "redefinition"
    (let ((m (make-module)))
      (beautify-user-module! m)

      ;; The previous value of `round' must still be visible at the time the
      ;; new `round' is defined.  According to R5RS (Section 5.2.1), `define'
      ;; should behave like `set!' in this case (except that in the case of
      ;; Guile, we respect module boundaries).
      (eval '(define round round) m)
      (eq? (module-ref m 'round) round)))

  (with-test-prefix "missing or extra expressions"

    (pass-if-syntax-error "(define)"
      exception:generic-syncase-error
      (eval '(define)
	    (interaction-environment)))))

(with-test-prefix "internal define"

  (pass-if "internal defines become letrec"
    (eval '(let ((a identity) (b identity) (c identity))
             (define (a x) (if (= x 0) 'a (b (- x 1))))
             (define (b x) (if (= x 0) 'b (c (- x 1))))
             (define (c x) (if (= x 0) 'c (a (- x 1))))
             (and (eq? 'a (a 0) (a 3))
                  (eq? 'b (a 1) (a 4))
                  (eq? 'c (a 2) (a 5))))
          (interaction-environment)))

  (pass-if "binding is created before expression is evaluated"
    ;; Internal defines are equivalent to `letrec' (R5RS, Section 5.2.2).
    (= (eval '(let ()
                (define foo
                  (begin
                    (set! foo 1)
                    (+ foo 1)))
                foo)
             (interaction-environment))
       2))

  (pass-if "internal defines with begin"
    (false-if-exception
     (eval '(let ((a identity) (b identity) (c identity))
              (define (a x) (if (= x 0) 'a (b (- x 1))))
              (begin
                (define (b x) (if (= x 0) 'b (c (- x 1)))))
              (define (c x) (if (= x 0) 'c (a (- x 1))))
              (and (eq? 'a (a 0) (a 3))
                   (eq? 'b (a 1) (a 4))
                   (eq? 'c (a 2) (a 5))))
           (interaction-environment))))

  (pass-if "internal defines with empty begin"
    (false-if-exception
     (eval '(let ((a identity) (b identity) (c identity))
              (define (a x) (if (= x 0) 'a (b (- x 1))))
              (begin)
              (define (b x) (if (= x 0) 'b (c (- x 1))))
              (define (c x) (if (= x 0) 'c (a (- x 1))))
              (and (eq? 'a (a 0) (a 3))
                   (eq? 'b (a 1) (a 4))
                   (eq? 'c (a 2) (a 5))))
           (interaction-environment))))

  (pass-if "internal defines with macro application"
    (false-if-exception
     (eval '(begin
              (defmacro my-define forms
                (cons 'define forms))
              (let ((a identity) (b identity) (c identity))
                (define (a x) (if (= x 0) 'a (b (- x 1))))
                (my-define (b x) (if (= x 0) 'b (c (- x 1))))
                (define (c x) (if (= x 0) 'c (a (- x 1))))
                (and (eq? 'a (a 0) (a 3))
                     (eq? 'b (a 1) (a 4))
                     (eq? 'c (a 2) (a 5)))))
           (interaction-environment))))

  (pass-if-syntax-error "missing body expression"
    exception:missing-body-expr
    (eval '(let () (define x #t))
          (interaction-environment))))

(with-test-prefix "top-level define-values"

  (pass-if "zero values"
    (eval '(begin (define-values () (values))
                  #t)
          (interaction-environment)))

  (pass-if-equal "one value"
      1
    (eval '(begin (define-values (x) 1)
                  x)
          (interaction-environment)))

  (pass-if-equal "two values"
      '(2 3)
    (eval '(begin (define-values (x y) (values 2 3))
                  (list x y))
          (interaction-environment)))

  (pass-if-equal "three values"
      '(4 5 6)
    (eval '(begin (define-values (x y z) (values 4 5 6))
                  (list x y z))
          (interaction-environment)))

  (pass-if-equal "one value with tail"
      '(a (b c d))
    (eval '(begin (define-values (x . y) (values 'a 'b 'c 'd))
                  (list x y))
          (interaction-environment)))

  (pass-if-equal "two values with tail"
      '(x y (z w))
    (eval '(begin (define-values (x y . z) (values 'x 'y 'z 'w))
                  (list x y z))
          (interaction-environment)))

  (pass-if-equal "just tail"
      '(1 2 3)
    (eval '(begin (define-values x (values 1 2 3))
                  x)
          (interaction-environment)))

  (pass-if-exception "expected 0 values, got 1"
      exception:define-values-wrong-number-of-return-values
    (eval '(define-values () 1)
          (interaction-environment)))

  (pass-if-exception "expected 1 value, got 0"
      exception:define-values-wrong-number-of-return-values
    (eval '(define-values (x) (values))
          (interaction-environment)))

  (pass-if-exception "expected 1 value, got 2"
      exception:define-values-wrong-number-of-return-values
    (eval '(define-values (x) (values 1 2))
          (interaction-environment)))

  (pass-if-exception "expected 1 value with tail, got 0"
      exception:define-values-wrong-number-of-return-values
    (eval '(define-values (x . y) (values))
          (interaction-environment)))

  (pass-if-exception "expected 2 value with tail, got 1"
      exception:define-values-wrong-number-of-return-values
    (eval '(define-values (x y . z) 1)
          (interaction-environment)))

  (pass-if "redefinition"
    (let ((m (make-module)))
      (beautify-user-module! m)

      ;; The previous values of `floor' and `round' must still be
      ;; visible at the time the new `floor' and `round' are defined.
      (eval '(define-values (floor round) (values floor round)) m)
      (and (eq? (module-ref m 'floor) floor)
           (eq? (module-ref m 'round) round))))

  (with-test-prefix "missing expression"

    (pass-if-syntax-error "(define-values)"
      exception:generic-syncase-error
      (eval '(define-values)
	    (interaction-environment)))))

(with-test-prefix "internal define-values"

  (pass-if "zero values"
    (let ()
      (define-values () (values))
      #t))

  (pass-if-equal "one value"
      1
    (let ()
      (define-values (x) 1)
      x))

  (pass-if-equal "two values"
      '(2 3)
    (let ()
      (define-values (x y) (values 2 3))
      (list x y)))

  (pass-if-equal "three values"
      '(4 5 6)
    (let ()
      (define-values (x y z) (values 4 5 6))
      (list x y z)))

  (pass-if-equal "one value with tail"
      '(a (b c d))
    (let ()
      (define-values (x . y) (values 'a 'b 'c 'd))
      (list x y)))

  (pass-if-equal "two values with tail"
      '(x y (z w))
    (let ()
      (define-values (x y . z) (values 'x 'y 'z 'w))
      (list x y z)))

  (pass-if-equal "just tail"
      '(1 2 3)
    (let ()
      (define-values x (values 1 2 3))
      x))

  (pass-if-exception "expected 0 values, got 1"
      exception:define-values-wrong-number-of-return-values
    (eval '(let ()
             (define-values () 1)
             #f)
          (interaction-environment)))

  (pass-if-exception "expected 1 value, got 0"
      exception:define-values-wrong-number-of-return-values
    (eval '(let ()
             (define-values (x) (values))
             #f)
          (interaction-environment)))

  (pass-if-exception "expected 1 value, got 2"
      exception:define-values-wrong-number-of-return-values
    (eval '(let ()
             (define-values (x) (values 1 2))
             #f)
          (interaction-environment)))

  (pass-if-exception "expected 1 value with tail, got 0"
      exception:define-values-wrong-number-of-return-values
    (eval '(let ()
             (define-values (x . y) (values))
             #f)
          (interaction-environment)))

  (pass-if-exception "expected 2 value with tail, got 1"
      exception:define-values-wrong-number-of-return-values
    (eval '(let ()
             (define-values (x y . z) 1)
             #f)
          (interaction-environment)))

  (with-test-prefix "missing expression"

    (pass-if-syntax-error "(define-values)"
      exception:generic-syncase-error
      (eval '(let ()
               (define-values)
               #f)
	    (interaction-environment)))))

(with-test-prefix "set!"

  (with-test-prefix "missing or extra expressions"

    (pass-if-syntax-error "(set!)"
      exception:bad-set!
      (eval '(set!)
	    (interaction-environment)))

    (pass-if-syntax-error "(set! 1)"
      exception:bad-set!
      (eval '(set! 1)
	    (interaction-environment)))

    (pass-if-syntax-error "(set! 1 2 3)"
      exception:bad-set!
      (eval '(set! 1 2 3)
	    (interaction-environment))))

  (with-test-prefix "bad variable"

    (pass-if-syntax-error "(set! \"\" #t)"
      exception:bad-set!
      (eval '(set! "" #t)
	    (interaction-environment)))

    (pass-if-syntax-error "(set! 1 #t)"
      exception:bad-set!
      (eval '(set! 1 #t)
	    (interaction-environment)))

    (pass-if-syntax-error "(set! #t #f)"
      exception:bad-set!
      (eval '(set! #t #f)
	    (interaction-environment)))

    (pass-if-syntax-error "(set! #f #t)"
      exception:bad-set!
      (eval '(set! #f #t)
	    (interaction-environment)))

    (pass-if-syntax-error "(set! #\\space #f)"
      exception:bad-set!
      (eval '(set! #\space #f)
	    (interaction-environment)))))

(with-test-prefix "quote"

  (with-test-prefix "missing or extra expression"

    (pass-if-syntax-error "(quote)"
      exception:bad-quote
      (eval '(quote)
	    (interaction-environment)))

    (pass-if-syntax-error "(quote a b)"
      exception:bad-quote
      (eval '(quote a b)
	    (interaction-environment)))))

(with-test-prefix "while"
  
  (define (unreachable)
    (error "unreachable code has been reached!"))
  
  ;; Return a new procedure COND which when called (COND) will return #t the
  ;; first N times, then #f, then any further call is an error.  N=0 is
  ;; allowed, in which case #f is returned by the first call.
  (define (make-iterations-cond n)
    (lambda ()
      (cond ((not n)
	     (error "oops, condition re-tested after giving false"))
	    ((= 0 n)
	     (set! n #f)
	     #f)
	    (else
	     (set! n (1- n))
	     #t))))
  

  (pass-if-syntax-error "too few args" exception:generic-syncase-error
    (eval '(while) (interaction-environment)))
  
  (with-test-prefix "empty body"
    (do ((n 0 (1+ n)))
	((> n 5))
      (pass-if n
	(eval `(letrec ((make-iterations-cond
                         (lambda (n)
                           (lambda ()
                             (cond ((not n)
                                    (error "oops, condition re-tested after giving false"))
                                   ((= 0 n)
                                    (set! n #f)
                                    #f)
                                   (else
                                    (set! n (1- n))
                                    #t))))))
                 (let ((cond (make-iterations-cond ,n)))
                   (while (cond))
                   #t))
              (interaction-environment)))))
  
  (pass-if "initially false"
    (while #f
      (unreachable))
    #t)
  
  (with-test-prefix "iterations"
    (do ((n 0 (1+ n)))
	((> n 5))
      (pass-if n
	(let ((cond (make-iterations-cond n))
	      (i    0))
	  (while (cond)
	    (set! i (1+ i)))
	  (= i n)))))
  
  (with-test-prefix "break"
    
    (pass-if "normal return"
      (not (while #f (error "not reached"))))

    (pass-if "no args"
      (while #t (break)))

    (pass-if "multiple values"
      (equal? '(1 2 3)
              (call-with-values
                  (lambda () (while #t (break 1 2 3)))
                list)))

    (with-test-prefix "from cond"
      (pass-if "first"
	(while (begin
		 (break)
		 (unreachable))
	  (unreachable))
	#t)
      
      (do ((n 0 (1+ n)))
	  ((> n 5))
	(pass-if n
	  (let ((cond (make-iterations-cond n))
		(i    0))
	    (while (if (cond)
		       #t
		       (begin
			 (break)
			 (unreachable)))
	      (set! i (1+ i)))
	    (= i n)))))
    
    (with-test-prefix "from body"
      (pass-if "first"
	(while #t
	  (break)
	  (unreachable))
	#t)
      
      (do ((n 0 (1+ n)))
	  ((> n 5))
	(pass-if n
	  (let ((cond (make-iterations-cond n))
		(i    0))
	    (while #t
	      (if (not (cond))
		  (begin
		    (break)
		    (unreachable)))
	      (set! i (1+ i)))
	    (= i n)))))
    
    (pass-if "from nested"
      (while #t
	(let ((outer-break break))
	  (while #t
	    (outer-break)
	    (unreachable)))
	(unreachable))
      #t)
    
    (pass-if "from recursive"
      (let ((outer-break #f))
	(define (r n)
	  (while #t
	    (if (eq? n 'outer)
		(begin
		  (set! outer-break break)
		  (r 'inner))
		(begin
		  (outer-break)
		  (unreachable))))
	  (if (eq? n 'inner)
	      (error "broke only from inner loop")))
	(r 'outer))
      #t))
  
  (with-test-prefix "continue"
    
    (pass-if-syntax-error "too many args" exception:too-many-args
      (eval '(while #t
               (continue 1))
            (interaction-environment)))
    
    (with-test-prefix "from cond"
      (do ((n 0 (1+ n)))
	  ((> n 5))
	(pass-if n
	  (let ((cond (make-iterations-cond n))
		(i    0))
	    (while (if (cond)
		       (begin
			 (set! i (1+ i))
			 (continue)
			 (unreachable))
		       #f)
	      (unreachable))
	    (= i n)))))
    
    (with-test-prefix "from body"
      (do ((n 0 (1+ n)))
	  ((> n 5))
	(pass-if n
	  (let ((cond (make-iterations-cond n))
		(i    0))
	    (while (cond)
	      (set! i (1+ i))
	      (continue)
	      (unreachable))
	    (= i n)))))
    
    (pass-if "from nested"
      (let ((cond (make-iterations-cond 3)))
	(while (cond)
	  (let ((outer-continue continue))
	    (while #t
	      (outer-continue)
	      (unreachable)))))
      #t)
    
    (pass-if "from recursive"
      (let ((outer-continue #f))
	(define (r n)
	  (let ((cond  (make-iterations-cond 3))
		(first #t))
	    (while (begin
		     (if (and (not first)
			      (eq? n 'inner))
			 (error "continued only to inner loop"))
		     (cond))
	      (set! first #f)
	      (if (eq? n 'outer)
		  (begin
		    (set! outer-continue continue)
		    (r 'inner))
		  (begin
		    (outer-continue)
		    (unreachable))))))
	(r 'outer))
      #t)))

(with-test-prefix "syntax-rules"

  (pass-if-equal "custom ellipsis within normal ellipsis"
      '((((a x) (a y) (a …))
         ((b x) (b y) (b …))
         ((c x) (c y) (c …)))
        (((a x) (b x) (c x))
         ((a y) (b y) (c y))
         ((a …) (b …) (c …))))
    (let ()
      (define-syntax foo
        (syntax-rules ()
          ((_ y ...)
           (syntax-rules … ()
             ((_ x …)
              '((((x y) ...) …)
                (((x y) …) ...)))))))
      (define-syntax bar (foo x y …))
      (bar a b c)))

  (pass-if-equal "normal ellipsis within custom ellipsis"
      '((((a x) (a y) (a z))
         ((b x) (b y) (b z))
         ((c x) (c y) (c z)))
        (((a x) (b x) (c x))
         ((a y) (b y) (c y))
         ((a z) (b z) (c z))))
    (let ()
      (define-syntax foo
        (syntax-rules … ()
          ((_ y …)
           (syntax-rules ()
             ((_ x ...)
              '((((x y) …) ...)
                (((x y) ...) …)))))))
      (define-syntax bar (foo x y z))
      (bar a b c)))

  ;; This test is given in SRFI-46.
  (pass-if-equal "custom ellipsis is handled hygienically"
      '((1) 2 (3) (4))
    (let-syntax
        ((f (syntax-rules ()
              ((f ?e)
               (let-syntax
                   ((g (syntax-rules --- ()
                         ((g (??x ?e) (??y ---))
                          '((??x) ?e (??y) ---)))))
                 (g (1 2) (3 4)))))))
      (f ---))))

(with-test-prefix "syntax-error"

  (pass-if-syntax-error "outside of macro without args"
    "test error"
    (eval '(syntax-error "test error")
          (interaction-environment)))

  (pass-if-syntax-error "outside of macro with args"
    "test error x \\(y z\\)"
    (eval '(syntax-error "test error" x (y z))
          (interaction-environment)))

  (pass-if-equal "within macro"
      '(simple-let
        "expected an identifier but got (z1 z2)"
        (simple-let ((y (* x x))
                     ((z1 z2) (values x x)))
          (+ y 1)))
    (catch 'syntax-error
      (lambda ()
        (eval '(let ()
                 (define-syntax simple-let
                   (syntax-rules ()
                     ((_ (head ... ((x . y) val) . tail)
                         body1 body2 ...)
                      (syntax-error
                       "expected an identifier but got"
                       (x . y)))
                     ((_ ((name val) ...) body1 body2 ...)
                      ((lambda (name ...) body1 body2 ...)
                       val ...))))
                 (define (foo x)
                   (simple-let ((y (* x x))
                                ((z1 z2) (values x x)))
                     (+ y 1)))
                 foo)
              (interaction-environment))
        (error "expected syntax-error exception"))
      (lambda (k who what where form . maybe-subform)
        (list who what form)))))

(with-test-prefix "syntax-case"
  
  (pass-if-syntax-error "duplicate pattern variable"
    '(syntax-case . "duplicate pattern variable")
    (eval '(lambda (e)
             (syntax-case e ()
               ((a b c d e d f) #f)))
          (interaction-environment)))

  (with-test-prefix "misplaced ellipses"

    (pass-if-syntax-error "bare ellipsis"
      '(syntax-case . "misplaced ellipsis")
      (eval '(lambda (e)
               (syntax-case e ()
                 (... #f)))
            (interaction-environment)))

    (pass-if-syntax-error "ellipsis singleton"
      '(syntax-case . "misplaced ellipsis")
      (eval '(lambda (e)
               (syntax-case e ()
                 ((...) #f)))
            (interaction-environment)))

    (pass-if-syntax-error "ellipsis in car"
      '(syntax-case . "misplaced ellipsis")
      (eval '(lambda (e)
               (syntax-case e ()
                 ((... . _) #f)))
            (interaction-environment)))

    (pass-if-syntax-error "ellipsis in cdr"
      '(syntax-case . "misplaced ellipsis")
      (eval '(lambda (e)
               (syntax-case e ()
                 ((_ . ...) #f)))
            (interaction-environment)))

    (pass-if-syntax-error "two ellipses in the same list"
      '(syntax-case . "misplaced ellipsis")
      (eval '(lambda (e)
               (syntax-case e ()
                 ((x ... y ...) #f)))
            (interaction-environment)))

    (pass-if-syntax-error "three ellipses in the same list"
      '(syntax-case . "misplaced ellipsis")
      (eval '(lambda (e)
               (syntax-case e ()
                 ((x ... y ... z ...) #f)))
            (interaction-environment)))))

(with-test-prefix "with-ellipsis"

  (pass-if-equal "simple"
      '(a 1 2 3)
    (let ()
      (define-syntax define-quotation-macros
        (lambda (x)
          (syntax-case x ()
            ((_ (macro-name head-symbol) ...)
             #'(begin (define-syntax macro-name
                        (lambda (x)
                          (with-ellipsis …
                            (syntax-case x ()
                              ((_ x …)
                               #'(quote (head-symbol x …)))))))
                      ...)))))
      (define-quotation-macros (quote-a a) (quote-b b))
      (quote-a 1 2 3)))

  (pass-if-equal "disables normal ellipsis"
      '(a ...)
    (let ()
      (define-syntax foo
        (lambda (x)
          (with-ellipsis …
            (syntax-case x ()
              ((_)
               #'(quote (a ...)))))))
      (foo)))

  (pass-if-equal "doesn't affect ellipsis for generated code"
      '(a b c)
    (let ()
      (define-syntax quotation-macro
        (lambda (x)
          (with-ellipsis …
            (syntax-case x ()
              ((_)
               #'(lambda (x)
                   (syntax-case x ()
                     ((_ x ...)
                      #'(quote (x ...))))))))))
      (define-syntax kwote (quotation-macro))
      (kwote a b c)))

  (pass-if-equal "propagates into syntax binders"
      '(a b c)
    (let ()
      (with-ellipsis …
        (define-syntax kwote
          (lambda (x)
            (syntax-case x ()
              ((_ x …)
               #'(quote (x …))))))
        (kwote a b c))))

  (pass-if-equal "works with local-eval"
      5
    (let ((env (with-ellipsis … (the-environment))))
      (local-eval '(syntax-case #'(a b c d e) ()
                     ((x …)
                      (length #'(x …))))
                  env))))

;;; Local Variables:
;;; eval: (put 'pass-if-syntax-error 'scheme-indent-function 1)
;;; eval: (put 'with-ellipsis 'scheme-indent-function 1)
;;; End: