+// revisions: migrate nll
+//[migrate]compile-flags: -Z borrowck=migrate
+#![cfg_attr(nll, feature(nll))]
+
+// compile-pass
+
+// Test that we propagate region relations from closures precisely when there is
+// more than one non-local lower bound.
+
+// In this case the closure has signature
+// |x: &'4 mut (&'5 (&'1 str, &'2 str), &'3 str)| -> ..
+// We end up with a `'3: '5` constraint that we can propagate as
+// `'3: '1`, `'3: '2`, but previously we approximated it as `'3: 'static`.
+
+// As an optimization, we primarily propagate bounds for the "representative"
+// of each SCC. As such we have these two similar cases where hopefully one
+// of them will test the case we want (case2, when this test was added).
+mod case1 {
+ fn f(s: &str) {
+ g(s, |x| h(x));
+ }
+
+ fn g<T, F>(_: T, _: F)
+ where F: Fn(&mut (&(T, T), T)) {}
+
+ fn h<T>(_: &mut (&(T, T), T)) {}
+}
+
+mod case2 {
+ fn f(s: &str) {
+ g(s, |x| h(x));
+ }
+
+ fn g<T, F>(_: T, _: F)
+ where F: Fn(&mut (T, &(T, T))) {}
+
+ fn h<T>(_: &mut (T, &(T, T))) {}
+}
+
+fn main() {}