typed-racket/typed-racket-test/unit-tests/inequalities.rkt
Andrew Kent 81b134cbb9 add refinement types, linear expr objs, and ineq props (#510)
This PR adds about half of the needed primitives and logic for
reasoning about linear integer arithmetic in programs with interesting
dependent types. Things have been added in a way s.t. programs will
still continue to typecheck as they did, but if you want integer literals
and certain operations (e.g. *,+,<,<=,=,>=,>) to include linear inequality
information by default, you need to include the
'#:with-linear-integer-arithmetic' keyword at the top of your module.

The other features needed to get TR to be able to check things like
verified vector operations will be to ajust function types so
dependencies can exist between arguments and a minor tweak to get
type inference to consider the symbolic objects of functions arguments.
These features should be coming shortly in a future pull request.
2017-03-27 14:32:29 -04:00

285 lines
9.6 KiB
Racket

#lang racket/base
(require "test-utils.rkt"
rackunit racket/format
(rep prop-rep)
(types abbrev prop-ops)
(logic ineq)
(for-syntax racket/base syntax/parse))
(provide tests)
(gen-test-main)
;; binding these means props that mention #'x, #'y, and #'z
;; will be referring to identifiers w/ variable bindings
;; (and props about things w/o variable bindings are erased
;; since top level ids are mutable)
(define q 42)
(define r 42)
(define t 42)
(define x 42)
(define y 42)
(define z 42)
(define tests
(let ([q (-id-path #'q)]
[r (-id-path #'r)]
[t (-id-path #'t)]
[x (-id-path #'x)]
[y (-id-path #'y)]
[z (-id-path #'z)])
(test-suite
"LExps and Inequalities"
(test-suite
"LExp Basics"
;; some sanity checks on the construction of LExps
;; and basic properties about them
(check-equal? (-lexp (list 1 x))
(-lexp x))
(check-equal? (-lexp (list 1 x))
(-lexp 0 x))
(check-equal? (-lexp 0
(list 1 x)
(list 1 x))
(-lexp 0 x x))
(check-equal? (-lexp 0
(list 1 x)
(list 1 x))
(-lexp (list 2 x)))
(check-equal? (constant-LExp? (-lexp 0
(list 1 x)
(list 1 x)))
#f)
(check-equal? (constant-LExp? (-lexp 0
(list 1 x)
(list -1 x)))
0)
(check-equal? (constant-LExp? (-lexp 42))
42)
(check-equal? (constant-LExp? (-lexp -42))
-42))
(test-suite
"Leq Constructor Simplifications"
;; do obviously valid leqs get erased? do
;; others get turned into actual LeqProps, etc
(check-equal? (-leq (-lexp 1) (-lexp 2)) -tt)
(check-equal? (-leq (-lexp 2) (-lexp 1)) -ff)
(check-equal? (-leq x
x)
-tt)
(check-true (LeqProp? (-leq x
(-id-path #'y))))
(check-true (LeqProp? (-leq (-lexp (list 2 x))
x)))
(check-true (LeqProp? (-leq (-lexp 42 x)
x)))
(check-true (LeqProp? (-leq x
(-lexp (list 2 x)))))
(check-true (LeqProp? (-leq x
(-lexp 42 x))))
(check-true (LeqProp? (-leq (-lexp (list 2 x))
x)))
(check-true (LeqProp? (negate-prop
(-leq (-lexp (list 2 x))
x))))
(check-equal? (negate-prop
(-leq (-lexp (list 2 x))
x))
(-leq (-lexp 1 x)
(-lexp (list 2 x)))))
(test-suite
"Simple Satisfiability"
(check-true (satisfiable-Leqs?
(list (-leq (-lexp (list 2 x))
x))))
(check-false (satisfiable-Leqs?
(list (-leq (-lexp (list 2 x)) x)
(negate-prop
(-leq (-lexp (list 2 x)) x)))))
(check-false (satisfiable-Leqs?
(list (-leq (-lexp 0) (-lexp (list 1 y)))
(negate-prop (-leq (-lexp 0) (-lexp (list 1 y)))))))
)
(test-suite
"Leq binary relations"
;; contradictory-Leqs?
(check-false (contradictory-Leqs?
(-leq (-lexp (list 2 x)) x)
(-leq (-lexp (list 2 x)) x)))
(check-false (contradictory-Leqs?
(-leq (-lexp (list 2 x)) x)
(-leq (-lexp (list 2 y)) x)))
(check-false (contradictory-Leqs?
(-leq (-lexp (list 2 x)) x)
(-leq x (-lexp (list 2 x)))))
(check-true (contradictory-Leqs?
(-leq (-lexp (list 2 x)) x)
(negate-prop
(-leq (-lexp (list 2 x)) x))))
(check-false (contradictory-Leqs?
(-leq (-lexp (list 2 x)) x)
(negate-prop
(-leq (-lexp (list 2 y)) y))))
;; complementary-Leqs?
(check-false (complementary-Leqs?
(-leq (-lexp (list 2 x)) x)
(-leq (-lexp (list 2 x)) x)))
(check-true (complementary-Leqs?
(-leq (-lexp (list 2 x)) x)
(-leq x (-lexp (list 2 x)))))
(check-true (complementary-Leqs?
(-leq (-lexp (list 2 x)) x)
(negate-prop (-leq (-lexp (list 2 x)) x))))
(check-false (complementary-Leqs?
(-leq (-lexp (list 2 x)) x)
(negate-prop (-leq (-lexp (list 2 y)) y))))
)
(test-suite
"Leq implication"
;; x + y <= z; 0 <= y; 0 <= x --> x <= z /\ y <= z
(check-true
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 1 x) (list 1 y))
(-lexp (list 1 z)))
(-leq (-lexp 0)
(-lexp (list 1 y)))
(-leq (-lexp 0)
(-lexp (list 1 x))))
(list (-leq (-lexp (list 1 x))
(-lexp (list 1 z)))
(-leq (-lexp (list 1 y))
(-lexp (list 1 z))))))
;; x + y <= z; 0 <= y; 0 <= x -/-> x <= z /\ y <= q
(check-false
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 1 x) (list 1 y))
(-lexp (list 1 z)))
(-leq (-lexp 0)
(-lexp (list 1 y)))
(-leq (-lexp 0)
(-lexp (list 1 x))))
(list (-leq (-lexp (list 1 x))
(-lexp (list 1 z)))
(-leq (-lexp (list 1 y))
(-lexp (list 1 q))))))
;; 7x <= 29 --> x <= 4
(check-true
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 7 x))
(-lexp 29)))
(list (-leq (-lexp (list 1 x))
(-lexp 4)))))
;; 7x <= 28 --> x <= 4
(check-true
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 7 x))
(-lexp 28)))
(list (-leq (-lexp (list 1 x))
(-lexp 4)))))
;; 7x <= 28 does not --> x <= 3
(check-false
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 7 x))
(-lexp 28)))
(list (-leq (-lexp (list 1 x))
(-lexp 3)))))
;; 7x <= 27 --> x <= 3
(check-true
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 7 x))
(-lexp 27)))
(list (-leq (-lexp (list 1 x))
(-lexp 3)))))
;; 4x+3y+9z+20q-100r + 42 <= 4x+3y+9z+20q+100r;
;; x <= y + z;
;; 29r <= x + y + z + q;
;; 0 <= x;
;; 0 <= x + y + z;
;; 0 <= x + z;
;; x <= z
;; z + 1 <= t
;; 0 <= x + y;
;; 0 <= x + r;
;; 0 <= x + r + q;
;; -->
;; 0 <= t
(check-true
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 4 x) (list 3 y) (list 9 z) (list 20 q) (list -100 r) 42)
(-lexp (list 4 x) (list 3 y) (list 9 z) (list 20 q) (list 100 r)))
(-leq (-lexp (list 1 x))
(-lexp (list 1 y) (list 1 z)))
(-leq (-lexp (list 29 r))
(-lexp (list 1 x) (list 1 y) (list 1 z) (list 1 q)))
(-leq (-lexp 0)
(-lexp (list 1 x)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 y) (list 1 z)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 z)))
(-leq (-lexp (list 1 x))
(-lexp (list 1 z)))
(-leq (-lexp (list 1 z) 1)
(-lexp (list 1 t)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 y)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 r)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 r) (list 1 q))))
(list (-leq (-lexp 0)
(-lexp (list 1 t))))))
;; 4x+3y+9z+20q-100r + 42 <= 4x+3y+9z+20q+100r;
;; x <= y + z;
;; 29r <= x + y + z + q;
;; 0 <= x;
;; 0 <= x + y + z;
;; 0 <= x + z;
;; x <= z
;; z + 1 <= t
;; 0 <= x + y;
;; 0 <= x + r;
;; 0 <= x + r + q;
;; -/->
;; t <= 0
(check-false
(Leqs-imply-Leqs?
(list (-leq (-lexp (list 4 x) (list 3 y) (list 9 z) (list 20 q) (list -100 r) 42)
(-lexp (list 4 x) (list 3 y) (list 9 z) (list 20 q) (list 100 r)))
(-leq (-lexp (list 1 x))
(-lexp (list 1 y) (list 1 z)))
(-leq (-lexp (list 29 r))
(-lexp (list 1 x) (list 1 y) (list 1 z) (list 1 q)))
(-leq (-lexp 0)
(-lexp (list 1 x)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 y) (list 1 z)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 z)))
(-leq (-lexp (list 1 x))
(-lexp (list 1 z)))
(-leq (-lexp (list 1 z) 1)
(-lexp (list 1 t)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 y)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 r)))
(-leq (-lexp 0)
(-lexp (list 1 x) (list 1 r) (list 1 q))))
(list (-leq (-lexp (list 1 t))
(-lexp 0))))))
))
)