moved renamed docs | diverging-fallback-option.rs

Author: Kivooeo

tests/ui/diverging-fallback-option.rs

@@ -0,0 +1,19 @@
+//@ run-pass
+
+#![allow(warnings)]
+
+//! Tests type inference fallback to `!` (never type) in `Option` context.
+//!
+//! Regression test for issues:
+//! - https://github.com/rust-lang/rust/issues/39808
+//! - https://github.com/rust-lang/rust/issues/39984
+//!
+//! Checks that when creating `Option` from a diverging expression,
+//! the type parameter defaults to `!` without requiring explicit annotations.
+
+fn main() {
+    // This expression diverges, so its type is `!`
+    let c = Some({ return; });
+    // The type of `c` is inferred as `Option<!>`
+    c.unwrap();
+}