1 files changed, 136 insertions, 0 deletions
diff --git a/third_party/rust/rental/tests/complex_mut.rs b/third_party/rust/rental/tests/complex_mut.rs
new file mode 100644
index 0000000000..3ea44440ab
--- /dev/null
+++ b/third_party/rust/rental/tests/complex_mut.rs
@@ -0,0 +1,136 @@
+#[macro_use]
+extern crate rental;
+
+
+pub struct Foo {
+	i: i32,
+}
+
+pub struct Bar<'a> {
+	foo: &'a mut Foo,
+}
+
+pub struct Baz<'a: 'b, 'b> {
+	bar: &'b mut Bar<'a>
+}
+
+pub struct Qux<'a: 'b, 'b: 'c, 'c> {
+	baz: &'c mut Baz<'a, 'b>
+}
+
+pub struct Xyzzy<'a: 'b, 'b: 'c, 'c: 'd, 'd> {
+	qux: &'d mut Qux<'a, 'b, 'c>
+}
+
+
+impl Foo {
+	pub fn borrow_mut<'a>(&'a mut self) -> Bar<'a> { Bar { foo: self } }
+	pub fn try_borrow_mut<'a>(&'a mut self) -> Result<Bar<'a>, ()> { Ok(Bar { foo: self }) }
+	pub fn fail_borrow_mut<'a>(&'a mut self) -> Result<Bar<'a>, ()> { Err(()) }
+}
+
+impl<'a> Bar<'a> {
+	pub fn borrow_mut<'b>(&'b mut self) -> Baz<'a, 'b> { Baz { bar: self } }
+	pub fn try_borrow_mut<'b>(&'b mut self) -> Result<Baz<'a, 'b>, ()> { Ok(Baz { bar: self }) }
+	pub fn fail_borrow_mut<'b>(&'b mut self) -> Result<Baz<'a, 'b>, ()> { Err(()) }
+}
+
+impl<'a: 'b, 'b> Baz<'a, 'b> {
+	pub fn borrow_mut<'c>(&'c mut self) -> Qux<'a, 'b, 'c> { Qux { baz: self } }
+	pub fn try_borrow_mut<'c>(&'c mut self) -> Result<Qux<'a, 'b, 'c>, ()> { Ok(Qux { baz: self }) }
+	pub fn fail_borrow_mut<'c>(&'c mut self) -> Result<Qux<'a, 'b, 'c>, ()> { Err(()) }
+}
+
+impl<'a: 'b, 'b: 'c, 'c> Qux<'a, 'b, 'c> {
+	pub fn borrow_mut<'d>(&'d mut self) -> Xyzzy<'a, 'b, 'c, 'd> { Xyzzy { qux: self } }
+	pub fn try_borrow_mut<'d>(&'d mut self) -> Result<Xyzzy<'a, 'b, 'c, 'd>, ()> { Ok(Xyzzy { qux: self }) }
+	pub fn fail_borrow_mut<'d>(&'d mut self) -> Result<Xyzzy<'a, 'b, 'c, 'd>, ()> { Err(()) }
+}
+
+
+rental! {
+	mod rentals {
+		use super::*;
+
+		#[rental_mut]
+		pub struct ComplexRent {
+			foo: Box<Foo>,
+			bar: Box<Bar<'foo>>,
+			baz: Box<Baz<'foo, 'bar>>,
+			qux: Box<Qux<'foo, 'bar, 'baz>>,
+			xyzzy: Xyzzy<'foo, 'bar, 'baz, 'qux>,
+		}
+	}
+}
+
+
+#[test]
+fn new() {
+	let foo = Foo { i: 5 };
+	let _ = rentals::ComplexRent::new(
+		Box::new(foo),
+		|foo| Box::new(foo.borrow_mut()),
+		|bar| Box::new(bar.borrow_mut()),
+		|baz| Box::new(baz.borrow_mut()),
+		|qux| qux.borrow_mut()
+	);
+
+	let foo = Foo { i: 5 };
+	let cm = rentals::ComplexRent::try_new(
+		Box::new(foo),
+		|foo| foo.try_borrow_mut().map(|bar| Box::new(bar)),
+		|bar| bar.try_borrow_mut().map(|baz| Box::new(baz)),
+		|baz| baz.try_borrow_mut().map(|qux| Box::new(qux)),
+		|qux| qux.try_borrow_mut()
+	);
+	assert!(cm.is_ok());
+
+	let foo = Foo { i: 5 };
+	let cm = rentals::ComplexRent::try_new(
+		Box::new(foo),
+		|foo| foo.try_borrow_mut().map(|bar| Box::new(bar)),
+		|bar| bar.try_borrow_mut().map(|baz| Box::new(baz)),
+		|baz| baz.try_borrow_mut().map(|qux| Box::new(qux)),
+		|qux| qux.fail_borrow_mut()
+	);
+	assert!(cm.is_err());
+}
+
+
+#[test]
+fn read() {
+	let foo = Foo { i: 5 };
+	let cm = rentals::ComplexRent::new(
+		Box::new(foo),
+		|foo| Box::new(foo.borrow_mut()),
+		|bar| Box::new(bar.borrow_mut()),
+		|baz| Box::new(baz.borrow_mut()),
+		|qux| qux.borrow_mut()
+	);
+	let i = cm.rent(|xyzzy| xyzzy.qux.baz.bar.foo.i);
+	assert_eq!(i, 5);
+
+	let iref = cm.ref_rent(|xyzzy| &xyzzy.qux.baz.bar.foo.i);
+	assert_eq!(*iref, 5);
+}
+
+
+#[test]
+fn write() {
+	let foo = Foo { i: 5 };
+	let mut cm = rentals::ComplexRent::new(
+		Box::new(foo),
+		|foo| Box::new(foo.borrow_mut()),
+		|bar| Box::new(bar.borrow_mut()),
+		|baz| Box::new(baz.borrow_mut()),
+		|qux| qux.borrow_mut()
+	);
+
+	{
+		let iref: &mut i32 = cm.ref_rent_mut(|xyzzy| &mut xyzzy.qux.baz.bar.foo.i);
+		*iref = 12;
+	}
+
+	let i = cm.rent(|xyzzy| xyzzy.qux.baz.bar.foo.i);
+	assert_eq!(i, 12);
+}