Add test case for #70019

Author: WindowsMEMZ

test/Concurrency/issue-70019.swift

@@ -0,0 +1,16 @@
+// RUN: %target-typecheck-verify-swift -swift-version 5
+// RUN: %target-typecheck-verify-swift -swift-version 5 -enable-library-evolution
+
+// REQUIRES: concurrency
+
+// https://github.com/apple/swift/issues/70019
+
+@usableFromInline
+struct Foo { // expected-note {{consider making struct 'Foo' conform to the 'Sendable' protocol}}
+  var integer: Int
+}
+
+struct Bar: Sendable {
+  // FIXME: This warning should only be thrown in library evolution mode. If @usableFromInline is removed from Foo the Sendable conformance is synthesized as expected.
+  var foo: Foo // expected-warning {{stored property 'foo' of 'Sendable'-conforming struct 'Bar' has non-sendable type 'Foo'}}
+}