Make quantifier splitting a two step process

This fixes a bug that affected Monad.dfy

2 files changed, 23 insertions, 0 deletions

diff --git a/Test/triggers/regression-tests.dfy b/Test/triggers/regression-tests.dfy
new file mode 100644
index 00000000..263e424a
--- /dev/null
+++ b/Test/triggers/regression-tests.dfy
@@ -0,0 +1,20 @@
+// RUN: %dafny /compile:0 /print:"%t.print" /dprint:"%t.dprint" /autoTriggers:1 /printTooltips "%s" > "%t"
+// RUN: %diff "%s.expect" "%t"
+
+// This tests checks that quantifier splitting is resilient to the fact that
+// certain statements (like calc) can return duplicate subexpressions. This was
+// once a problem, because a quantifier that got returned twice would get split
+// on the first pass over it, and would have its nely created children re-split
+// on the second pass. This created a split quantifier whose children were split
+// quantifiers, which violated an invariant of spliit quantifiers.
+
+abstract module Base { }
+
+module Blah refines Base {
+  lemma A() {
+    calc {
+	    forall b :: b;
+   	}
+  }
+}
+
diff --git a/Test/triggers/regression-tests.dfy.expect b/Test/triggers/regression-tests.dfy.expect
new file mode 100644
index 00000000..a03810fb
--- /dev/null
+++ b/Test/triggers/regression-tests.dfy.expect
@@ -0,0 +1,3 @@
+regression-tests.dfy(16,5): Warning: (!) No terms found to trigger on.

+

+Dafny program verifier finished with 2 verified, 0 errors