Fix failure when shrinking tests with duplicates in hypothesis-ruby tests

conjecture-rust/RELEASE.md

@@ -0,0 +1,4 @@
+RELEASE_TYPE: patch
+
+This release fixes an occasional assertion failure that could occur
+when shrinking a failing test.

conjecture-rust/src/engine.rs

@@ -408,15 +408,20 @@ where
  fn minimize_duplicated_blocks(&mut self) -> StepResult {
  let mut i = 0;
  let mut targets = self.calc_duplicates();
+
  while i < targets.len() {
  let target = mem::replace(&mut targets[i], Vec::new());
+ let max_target = *target.iter().max().unwrap();
+
  i += 1;
  assert!(target.len() > 0);
  let v = self.shrink_target.record[target[0]];
- let base = self.shrink_target.record.clone();
 
  let w = minimize_integer(v, |t| {
- let mut attempt = base.clone();
+ if max_target >= self.shrink_target.record.len() {
+ return Ok(false);
+ }
+ let mut attempt = self.shrink_target.record.clone();
  for i in &target {
  attempt[*i] = t
  }

hypothesis-ruby/RELEASE.md

@@ -0,0 +1,4 @@
+RELEASE_TYPE: patch
+
+This release fixes an occasional `RuntimeError` that could occur
+when shrinking a failing test.