---

yaml
---
r: 323059
b: refs/heads/tensorflow-next
c: 0e42771
h: refs/heads/master
i:
  323057: 91003af
  323055: 8151d5a

Author: swift-ci

[refs]

@@ -1461,4 +1461,4 @@ refs/heads/master-rebranch: 86e95c23aa0d37f24ec138b7853146c1cead2e40
 refs/heads/rdar-53901732: 9bd06af3284e18a109cdbf9aa59d833b24eeca7b
 refs/heads/revert-26776-subst-always-returns-a-type: 1b8e18fdd391903a348970a4c848995d4cdd789c
 refs/heads/tensorflow-merge: 8b854f62f80d4476cb383d43c4aac2001dde3cec
-refs/heads/tensorflow-next: 3a4993f76606eb3af817131a5927ce2d8c806625
+refs/heads/tensorflow-next: 0e427711e4ca7a3340e104d14d199b20c271ee92

branches/tensorflow-next/lib/AST/DiagnosticEngine.cpp

@@ -622,10 +622,14 @@ static DiagnosticKind toDiagnosticKind(DiagnosticState::Behavior behavior) {
   llvm_unreachable("Unhandled DiagnosticKind in switch.");
 }
 
-/// A special option only for compiler writers that causes Diagnostics to assert
-/// when a failure diagnostic is emitted. Intended for use in the debugger.
+// A special option only for compiler writers that causes Diagnostics to assert
+// when a failure diagnostic is emitted. Intended for use in the debugger.
 llvm::cl::opt<bool> AssertOnError("swift-diagnostics-assert-on-error",
                                   llvm::cl::init(false));
+// A special option only for compiler writers that causes Diagnostics to assert
+// when a warning diagnostic is emitted. Intended for use in the debugger.
+llvm::cl::opt<bool> AssertOnWarning("swift-diagnostics-assert-on-warning",
+                                    llvm::cl::init(false));
 
 DiagnosticState::Behavior DiagnosticState::determineBehavior(DiagID id) {
   auto set = [this](DiagnosticState::Behavior lvl) {
@@ -637,6 +641,8 @@ DiagnosticState::Behavior DiagnosticState::determineBehavior(DiagID id) {
     }
 
     assert((!AssertOnError || !anyErrorOccurred) && "We emitted an error?!");
+    assert((!AssertOnWarning || (lvl != Behavior::Warning)) &&
+           "We emitted a warning?!");
     previousBehavior = lvl;
     return lvl;
   };

branches/tensorflow-next/test/Interpreter/Inputs/testable_key_path_2.swift

@@ -0,0 +1,3 @@
+internal class TestClass {
+  internal var field = "goodbye"
+}

branches/tensorflow-next/test/Interpreter/testable_key_path.swift

@@ -0,0 +1,20 @@
+// RUN: %empty-directory(%t)
+// RUN: %target-build-swift -force-single-frontend-invocation -c -o %t/Module.o -enable-testing -parse-as-library -emit-module -emit-module-path %t/Module.swiftmodule -module-name Module %S/Inputs/testable_key_path_2.swift
+// RUN: %target-build-swift -o %t/a.out -I %t %s %t/Module.o
+// RUN: %target-run %t/a.out | %FileCheck %s
+
+// REQUIRES: executable_test
+
+@testable import Module
+
+let c = TestClass()
+
+print("You say \(c.field)")
+
+let kp = \TestClass.field
+
+c[keyPath: kp] = "hello"
+
+print("I say \(c.field)")
+
+// CHECK: I say hello