1 files changed, 104 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/borrow_interior_mutable_const/others.rs b/src/tools/clippy/tests/ui/borrow_interior_mutable_const/others.rs
new file mode 100644
index 000000000..eefeb1dec
--- /dev/null
+++ b/src/tools/clippy/tests/ui/borrow_interior_mutable_const/others.rs
@@ -0,0 +1,104 @@
+#![warn(clippy::borrow_interior_mutable_const)]
+#![allow(clippy::declare_interior_mutable_const, clippy::needless_borrow)]
+#![allow(const_item_mutation)]
+
+use std::borrow::Cow;
+use std::cell::{Cell, UnsafeCell};
+use std::fmt::Display;
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::sync::Once;
+
+const ATOMIC: AtomicUsize = AtomicUsize::new(5);
+const CELL: Cell<usize> = Cell::new(6);
+const ATOMIC_TUPLE: ([AtomicUsize; 1], Vec<AtomicUsize>, u8) = ([ATOMIC], Vec::new(), 7);
+const INTEGER: u8 = 8;
+const STRING: String = String::new();
+const STR: &str = "012345";
+const COW: Cow<str> = Cow::Borrowed("abcdef");
+const NO_ANN: &dyn Display = &70;
+static STATIC_TUPLE: (AtomicUsize, String) = (ATOMIC, STRING);
+const ONCE_INIT: Once = Once::new();
+
+// This is just a pointer that can be safely dereferenced,
+// it's semantically the same as `&'static T`;
+// but it isn't allowed to make a static reference from an arbitrary integer value at the moment.
+// For more information, please see the issue #5918.
+pub struct StaticRef<T> {
+    ptr: *const T,
+}
+
+impl<T> StaticRef<T> {
+    /// Create a new `StaticRef` from a raw pointer
+    ///
+    /// ## Safety
+    ///
+    /// Callers must pass in a reference to statically allocated memory which
+    /// does not overlap with other values.
+    pub const unsafe fn new(ptr: *const T) -> StaticRef<T> {
+        StaticRef { ptr }
+    }
+}
+
+impl<T> std::ops::Deref for StaticRef<T> {
+    type Target = T;
+
+    fn deref(&self) -> &'static T {
+        unsafe { &*self.ptr }
+    }
+}
+
+// use a tuple to make sure referencing a field behind a pointer isn't linted.
+const CELL_REF: StaticRef<(UnsafeCell<u32>,)> = unsafe { StaticRef::new(std::ptr::null()) };
+
+fn main() {
+    ATOMIC.store(1, Ordering::SeqCst); //~ ERROR interior mutability
+    assert_eq!(ATOMIC.load(Ordering::SeqCst), 5); //~ ERROR interior mutability
+
+    let _once = ONCE_INIT;
+    let _once_ref = &ONCE_INIT; //~ ERROR interior mutability
+    let _once_ref_2 = &&ONCE_INIT; //~ ERROR interior mutability
+    let _once_ref_4 = &&&&ONCE_INIT; //~ ERROR interior mutability
+    let _once_mut = &mut ONCE_INIT; //~ ERROR interior mutability
+    let _atomic_into_inner = ATOMIC.into_inner();
+    // these should be all fine.
+    let _twice = (ONCE_INIT, ONCE_INIT);
+    let _ref_twice = &(ONCE_INIT, ONCE_INIT);
+    let _ref_once = &(ONCE_INIT, ONCE_INIT).0;
+    let _array_twice = [ONCE_INIT, ONCE_INIT];
+    let _ref_array_twice = &[ONCE_INIT, ONCE_INIT];
+    let _ref_array_once = &[ONCE_INIT, ONCE_INIT][0];
+
+    // referencing projection is still bad.
+    let _ = &ATOMIC_TUPLE; //~ ERROR interior mutability
+    let _ = &ATOMIC_TUPLE.0; //~ ERROR interior mutability
+    let _ = &(&&&&ATOMIC_TUPLE).0; //~ ERROR interior mutability
+    let _ = &ATOMIC_TUPLE.0[0]; //~ ERROR interior mutability
+    let _ = ATOMIC_TUPLE.0[0].load(Ordering::SeqCst); //~ ERROR interior mutability
+    let _ = &*ATOMIC_TUPLE.1;
+    let _ = &ATOMIC_TUPLE.2;
+    let _ = (&&&&ATOMIC_TUPLE).0;
+    let _ = (&&&&ATOMIC_TUPLE).2;
+    let _ = ATOMIC_TUPLE.0;
+    let _ = ATOMIC_TUPLE.0[0]; //~ ERROR interior mutability
+    let _ = ATOMIC_TUPLE.1.into_iter();
+    let _ = ATOMIC_TUPLE.2;
+    let _ = &{ ATOMIC_TUPLE };
+
+    CELL.set(2); //~ ERROR interior mutability
+    assert_eq!(CELL.get(), 6); //~ ERROR interior mutability
+
+    assert_eq!(INTEGER, 8);
+    assert!(STRING.is_empty());
+
+    let a = ATOMIC;
+    a.store(4, Ordering::SeqCst);
+    assert_eq!(a.load(Ordering::SeqCst), 4);
+
+    STATIC_TUPLE.0.store(3, Ordering::SeqCst);
+    assert_eq!(STATIC_TUPLE.0.load(Ordering::SeqCst), 3);
+    assert!(STATIC_TUPLE.1.is_empty());
+
+    assert_eq!(NO_ANN.to_string(), "70"); // should never lint this.
+
+    let _ = &CELL_REF.0;
+}