1 files changed, 104 insertions, 0 deletions
diff --git a/src/test/ui/closures/2229_closure_analysis/migrations/precise_no_migrations.rs b/src/test/ui/closures/2229_closure_analysis/migrations/precise_no_migrations.rs
new file mode 100644
index 000000000..587d71c40
--- /dev/null
+++ b/src/test/ui/closures/2229_closure_analysis/migrations/precise_no_migrations.rs
@@ -0,0 +1,104 @@
+// run-pass
+
+#![deny(rust_2021_incompatible_closure_captures)]
+
+#[derive(Debug)]
+struct Foo(i32);
+impl Drop for Foo {
+    fn drop(&mut self) {
+        println!("{:?} dropped", self.0);
+    }
+}
+
+struct ConstainsDropField(Foo, Foo);
+
+// Test that if all paths starting at root variable that implement Drop are captured
+// then it doesn't trigger the lint.
+fn test_precise_analysis_simple_1() {
+    let t = (Foo(10), Foo(20), Foo(30));
+
+    let c = || {
+        let _t = t.0;
+        let _t = t.1;
+        let _t = t.2;
+    };
+
+    c();
+}
+
+// Test that if all paths starting at root variable that implement Drop are captured
+// then it doesn't trigger the lint.
+fn test_precise_analysis_simple_2() {
+    let t = ConstainsDropField(Foo(10), Foo(20));
+
+    let c = || {
+        let _t = t.0;
+        let _t = t.1;
+    };
+
+    c();
+}
+
+#[derive(Debug)]
+struct ContainsAndImplsDrop(Foo);
+impl Drop for ContainsAndImplsDrop {
+    fn drop(&mut self) {
+        println!("{:?} dropped", self.0);
+    }
+}
+
+// If a path isn't directly captured but requires Drop, then this tests that migrations aren't
+// needed if the a parent to that path is captured.
+fn test_precise_analysis_parent_captured_1() {
+    let t = ConstainsDropField(Foo(10), Foo(20));
+
+    let c = || {
+        let _t = t;
+    };
+
+    c();
+}
+
+// If a path isn't directly captured but requires Drop, then this tests that migrations aren't
+// needed if the a parent to that path is captured.
+fn test_precise_analysis_parent_captured_2() {
+    let t = ContainsAndImplsDrop(Foo(10));
+
+    let c = || {
+        let _t = t;
+    };
+
+    c();
+}
+
+struct S;
+impl Drop for S {
+    fn drop(&mut self) {}
+}
+
+struct T(S, S);
+struct U(T, T);
+
+// Test that if the path is longer than just one element, precise analysis works correctly.
+fn test_precise_analysis_long_path() {
+    let u = U(T(S, S), T(S, S));
+
+    let c = || {
+        let _x = u.0.0;
+        let _x = u.0.1;
+        let _x = u.1.0;
+        let _x = u.1.1;
+    };
+
+    c();
+}
+
+fn main() {
+    test_precise_analysis_simple_1();
+    test_precise_analysis_simple_2();
+
+    test_precise_analysis_parent_captured_1();
+    test_precise_analysis_parent_captured_2();
+
+    test_precise_analysis_long_path();
+}