[test] Add a test for two types import-as-member'd with the same name.

Unrelated to the previous commits, but good to Not Crash.

Author: jrose-apple

test/ClangImporter/Inputs/custom-modules/ImportAsMember.h

@@ -57,4 +57,12 @@ extern void IAMStruct1SelfComesLast(double x, struct IAMStruct1 s)
 extern void IAMStruct1SelfComesThird(int a, float b, struct IAMStruct1 s, double x)
     __attribute__((swift_name("Struct1.selfComesThird(a:b:self:x:)")));
 
+
+struct IAMMultipleNested {
+  int value;
+};
+
+typedef int MNInnerInt __attribute__((swift_name("IAMMultipleNested.Inner")));
+typedef float MNInnerFloat __attribute__((swift_name("IAMMultipleNested.Inner")));
+
 #endif // IMPORT_AS_MEMBER_H

test/ClangImporter/Inputs/frameworks/ImportAsMemberSubmodules.framework/Headers/Actual.h

@@ -1,3 +1,3 @@
-struct IAMOuter { int x; };
+struct IAMSOuter { int x; };
 
-struct IAMInner { int y; };
+struct IAMSInner { int y; };

test/ClangImporter/Inputs/frameworks/ImportAsMemberSubmodules.framework/Headers/Fwd.h

@@ -1,3 +1,3 @@
 // The order of these forward-declarations affects whether there was a bug.
-struct IAMOuter;
-struct IAMInner;
+struct IAMSOuter;
+struct IAMSInner;

test/ClangImporter/Inputs/frameworks/ImportAsMemberSubmodules.framework/Headers/ImportAsMemberSubmodules.apinotes

@@ -1,4 +1,4 @@
 Name: ImportAsMemberSubmodules
 Tags:
-- Name: IAMInner
-  SwiftName: IAMOuter.Inner
+- Name: IAMSInner
+  SwiftName: IAMSOuter.Inner

test/ClangImporter/import-as-member.swift

@@ -1,5 +1,7 @@
-// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -typecheck -F %S/Inputs/frameworks %s -verify
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -typecheck -F %S/Inputs/frameworks -I %S/Inputs/custom-modules %s -verify
 
+import ImportAsMember
 import ImportAsMemberSubmodules
 
-let _: IAMOuter.Inner?
+let _: IAMSOuter.Inner?
+let _: IAMMultipleNested.Inner? // expected-error {{ambiguous type name 'Inner' in 'IAMMultipleNested'}}