Add regression test

Author: jonas-schievink

src/test/ui/generator/issue-69039.rs

@@ -0,0 +1,30 @@
+// run-pass
+
+#![feature(generators, generator_trait)]
+
+use std::ops::{Generator, GeneratorState};
+
+fn my_scenario() -> impl Generator<String, Yield = &'static str, Return = String> {
+    |_arg: String| {
+        let my_name = yield "What is your name?";
+        let my_mood = yield "How are you feeling?";
+        format!("{} is {}", my_name.trim(), my_mood.trim())
+    }
+}
+
+fn main() {
+    let mut my_session = Box::pin(my_scenario());
+
+    assert_eq!(
+        my_session.as_mut().resume("_arg".to_string()),
+        GeneratorState::Yielded("What is your name?")
+    );
+    assert_eq!(
+        my_session.as_mut().resume("Your Name".to_string()),
+        GeneratorState::Yielded("How are you feeling?")
+    );
+    assert_eq!(
+        my_session.as_mut().resume("Sensory Organs".to_string()),
+        GeneratorState::Complete("Your Name is Sensory Organs".to_string())
+    );
+}