Fix visibility of synthesized Differential typedefs. (#7865)

* Fix visibility of synthesized `Differential` typedefs.

* Delete incorrect test.

2 files changed, 26 insertions, 14 deletions

diff --git a/tests/autodiff/differential-visibility.slang b/tests/autodiff/differential-visibility.slang
new file mode 100644
index 000000000..368155678
--- /dev/null
+++ b/tests/autodiff/differential-visibility.slang
@@ -0,0 +1,26 @@
+//TEST:SIMPLE(filecheck=CHECK): -target spirv
+// CHECK: OpEntryPoint 
+public interface IBSDF
+{
+    public float3 get_value();
+}
+
+public struct AnisotropicGGX // : IDifferentiable
+{
+    float2 alpha = {};
+    public __init() { }
+};
+
+public struct TestDiffVisibility : IBSDF, IDifferentiable
+{
+    public AnisotropicGGX D = {};
+    public __init() { }
+    public float3 get_value() { return { 0.3 }; }
+};
+
+[numthreads(1,1,1)]
+void main()
+{
+    TestDiffVisibility test = {};
+    test.get_value();
+}
diff --git a/tests/diagnostics/internal-visibility/interface-default-visibility.slang b/tests/diagnostics/internal-visibility/interface-default-visibility.slang
deleted file mode 100644
index 79df14143..000000000
--- a/tests/diagnostics/internal-visibility/interface-default-visibility.slang
+++ /dev/null
@@ -1,14 +0,0 @@
-//DIAGNOSTIC_TEST:SIMPLE(filecheck=CHECK):
-
-module m;
-
-public interface IFoo
-{
-    void foo(); // Should have public visibility by default.
-}
-
-public struct F : IFoo
-{
-    // CHECK:{{.*}}(13): error 30602:
-    void foo() {};
-}