Add tests for quantifier splitting and trigger generation

1 files changed, 21 insertions, 0 deletions

diff --git a/Test/triggers/loop-detection-is-not-too-strict.dfy b/Test/triggers/loop-detection-is-not-too-strict.dfy
new file mode 100644
index 00000000..c6722399
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+++ b/Test/triggers/loop-detection-is-not-too-strict.dfy
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+// RUN: %dafny /compile:0 /print:"%t.print" /dprint:"%t.dprint" /autoTriggers:1 "%s" > "%t"

+// RUN: %diff "%s.expect" "%t"

+

+// This test shows that the loop detection engine makes compromises when looking

+// for subexpressions matching a trigger; in particular, it allows a

+// subexpression to match a trigger without reporting a loop and without being

+// equal to that trigger, as long as the only differences are variable

+

+predicate P(x: int, y: int)

+

+method Test() {

+  // P(x, y) and P(y, x) might look like they would cause a loop. Since they

+  // only differ by their variables, though, they won't raise flags.

+  assume forall x: int, y: int :: P(x, y) == P(y, x);

+

+  // This works independent of extra parentheses:

+  assume forall x: int, y: int :: P(x, y) == (P(y, x));

+

+  // Contrast with the following:

+  assume forall x: int, y: int :: P(x, y) == P(x, y+1);

+}