Add regression test for issue #1505

Author: fpoli

prusti-tests/tests/verify_overflow/fail/issues/issue-1505.rs

@@ -0,0 +1,43 @@
+use prusti_contracts::*;
+
+// To inhibit constant-propagation optimizations:
+#[pure]
+fn id<T>(x: T) -> T { x}
+
+fn check_division(){
+    assert!(id(3i32) / 2 == 1);
+    assert!(id(-3i32) / 2 == -1);
+    assert!(id(3i32) / -2 == -1);
+    assert!(id(-3i32) / -2 == 1);
+    prusti_assert!(id(3i32) / 2 == 1);
+    prusti_assert!(id(-3i32) / 2 == -1);
+    prusti_assert!(id(3i32) / -2 == -1);
+    prusti_assert!(id(-3i32) / -2 == 1);
+
+    // Smoke test
+    assert!(false); //~ ERROR the asserted expression might not hold
+}
+
+fn check_modulo() {
+    assert!(id(10) % 3 == 1);
+    assert!(id(10) % -3 == 1);
+    assert!(id(-10) % 3 == -1);
+    assert!(id(-10) % -3 == -1);
+
+    assert!(id(3) % 3 == 0);
+    assert!(id(2) % 3 == 2);
+    assert!(id(1) % 3 == 1);
+    assert!(id(0) % 3 == 0);
+    assert!(id(-1) % 3 == -1);
+    assert!(id(-2) % 3 == -2);
+    assert!(id(-3) % 3 == 0);
+    assert!(id(-4) % 3 == -1);
+    assert!(id(-5) % 3 == -2);
+
+    assert!(id(-4) % 2 == 0);
+
+    // Smoke test
+    assert!(false); //~ ERROR the asserted expression might not hold
+}
+
+fn main(){}