prolog: is/2 arithmetic with + - * / mod abs, 11 tests

lib/prolog/tests/solve.sx

@@ -495,4 +495,124 @@
     pl-output-buffer)
   "hi\n")
 
+(define pl-s-env-arith1 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, 42)" pl-s-env-arith1)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, 42) binds X to 42"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith1 "X")))
+  42)
+
+(define pl-s-env-arith2 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, +(2, 3))" pl-s-env-arith2)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, +(2, 3)) binds X to 5"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith2 "X")))
+  5)
+
+(define pl-s-env-arith3 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, *(2, 3))" pl-s-env-arith3)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, *(2, 3)) binds X to 6"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith3 "X")))
+  6)
+
+(define pl-s-env-arith4 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, -(10, 3))" pl-s-env-arith4)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, -(10, 3)) binds X to 7"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith4 "X")))
+  7)
+
+(define pl-s-env-arith5 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, /(10, 2))" pl-s-env-arith5)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, /(10, 2)) binds X to 5"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith5 "X")))
+  5)
+
+(define pl-s-env-arith6 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, mod(10, 3))" pl-s-env-arith6)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, mod(10, 3)) binds X to 1"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith6 "X")))
+  1)
+
+(define pl-s-env-arith7 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, abs(-(0, 5)))" pl-s-env-arith7)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, abs(-(0, 5))) binds X to 5"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith7 "X")))
+  5)
+
+(define pl-s-env-arith8 {})
+
+(pl-solve-once!
+  pl-s-empty-db
+  (pl-s-goal "is(X, +(2, *(3, 4)))" pl-s-env-arith8)
+  (pl-mk-trail))
+
+(pl-s-test!
+  "is(X, +(2, *(3, 4))) binds X to 14 (nested)"
+  (pl-num-val (pl-walk-deep (dict-get pl-s-env-arith8 "X")))
+  14)
+
+(pl-s-test!
+  "is(5, +(2, 3)) succeeds (LHS num matches)"
+  (pl-solve-once!
+    pl-s-empty-db
+    (pl-s-goal "is(5, +(2, 3))" {})
+    (pl-mk-trail))
+  true)
+
+(pl-s-test!
+  "is(6, +(2, 3)) fails (LHS num mismatch)"
+  (pl-solve-once!
+    pl-s-empty-db
+    (pl-s-goal "is(6, +(2, 3))" {})
+    (pl-mk-trail))
+  false)
+
+(pl-s-test!
+  "is propagates bound vars on RHS"
+  (pl-solve-once!
+    pl-s-empty-db
+    (pl-s-goal "=(Y, 4), is(X, +(Y, 1)), =(X, 5)" {})
+    (pl-mk-trail))
+  true)
+
 (define pl-solve-tests-run! (fn () {:failed pl-s-test-fail :passed pl-s-test-pass :total pl-s-test-count :failures pl-s-test-failures}))