Add test

src/tests/Interop/CMakeLists.txt

@@ -57,6 +57,7 @@ add_subdirectory(MarshalAPI/FunctionPointer)
 add_subdirectory(NativeLibrary/NativeLibraryToLoad)
 add_subdirectory(DllImportAttribute/DllImportPath)
 add_subdirectory(DllImportAttribute/ExactSpelling)
+add_subdirectory(DllImportSearchPaths/NativeLibraryWithDependency)
 add_subdirectory(ICustomMarshaler/ConflictingNames)
 add_subdirectory(ICustomMarshaler/Primitives)
 add_subdirectory(LayoutClass)

src/tests/Interop/DllImportSearchPaths/DllImportSearchPathsTest.cs

@@ -65,6 +65,20 @@ public static void AssemblyDirectory_Fallback_Found()
             Environment.CurrentDirectory = currentDirectory;
         }
     }
+
+    [ConditionalFact(nameof(CanLoadAssemblyInSubdirectory))]
+    [PlatformSpecific(TestPlatforms.Windows)]
+    public static void AssemblyDirectory_SearchFlags_WithDependency_Found()
+    {
+        // Library and its dependency should be found in the assembly directory.
+        var assembly = Assembly.LoadFile(Path.Combine(Subdirectory, $"{nameof(DllImportSearchPathsTest)}.dll"));
+        var type = assembly.GetType(nameof(NativeLibraryWithDependency));
+        var method = type.GetMethod(nameof(NativeLibraryWithDependency.Sum));
+
+        int sum = (int)method.Invoke(null, new object[] { 1, 2 });
+        Assert.Equal(3, sum);
+        Console.WriteLine("NativeLibraryWithDependency.Sum returned {0}", sum);
+    }
 }
 
 public class NativeLibraryPInvoke
@@ -93,3 +107,18 @@ public static int Sum(int a, int b)
     [DefaultDllImportSearchPaths(DllImportSearchPath.AssemblyDirectory | DllImportSearchPath.System32)]
     static extern int NativeSum(int arg1, int arg2);
 }
+
+public class NativeLibraryWithDependency
+{
+    public static int Sum(int a, int b)
+    {
+        return CallDependencySum(a, b);
+    }
+
+    // For LoadLibrary on Windows, search flags, like that represented by System32, are incompatible with
+    // looking at a specific path (per AssemblyDirectory), so we specify both flags to validate that we do
+    // not incorrectly use both when looking in the assembly directory.
+    [DllImport(nameof(NativeLibraryWithDependency))]
+    [DefaultDllImportSearchPaths(DllImportSearchPath.AssemblyDirectory | DllImportSearchPath.System32)]
+    static extern int CallDependencySum(int a, int b);
+}

src/tests/Interop/DllImportSearchPaths/DllImportSearchPathsTest.csproj

@@ -9,6 +9,7 @@
     <Compile Include="*.cs" />
     <Compile Include="../NativeLibrary/NativeLibraryToLoad/NativeLibraryToLoad.cs" />
     <CMakeProjectReference Include="../NativeLibrary/NativeLibraryToLoad/CMakeLists.txt" />
+    <CMakeProjectReference Include="NativeLibraryWithDependency/CMakeLists.txt" />
   </ItemGroup>
 
   <PropertyGroup>
@@ -18,7 +19,9 @@
   <Target Name="SetUpSubdirectoryNative" AfterTargets="CopyNativeProjectBinaries">
     <ItemGroup>
       <NativeLibrariesToMove Include="$(OutDir)/libNativeLibrary.*" />
+      <NativeLibrariesToMove Include="$(OutDir)/libNativeLibraryWithDependency.*" />
       <NativeLibrariesToMove Include="$(OutDir)/NativeLibrary.*" />
+      <NativeLibrariesToMove Include="$(OutDir)/NativeLibraryWithDependency.*" />
     </ItemGroup>
     <Move SourceFiles="@(NativeLibrariesToMove)" DestinationFiles="@(NativeLibrariesToMove -> '$(LibrarySubdirectory)/%(Filename)%(Extension)')"/>
   </Target>

src/tests/Interop/DllImportSearchPaths/NativeLibraryWithDependency/CMakeLists.txt

@@ -0,0 +1,8 @@
+project(NativeLibraryWithDependency)
+include("${CLR_INTEROP_TEST_ROOT}/Interop.cmake")
+
+add_library(Dependency SHARED Dependency.cpp)
+target_link_libraries(Dependency PRIVATE ${LINK_LIBRARIES_ADDITIONAL})
+
+add_library(NativeLibraryWithDependency SHARED NativeLibraryWithDependency.cpp)
+target_link_libraries(NativeLibraryWithDependency PRIVATE Dependency ${LINK_LIBRARIES_ADDITIONAL})

src/tests/Interop/DllImportSearchPaths/NativeLibraryWithDependency/Dependency.cpp

@@ -0,0 +1,10 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#include <platformdefines.h>
+
+extern "C" DLL_EXPORT int STDMETHODCALLTYPE Sum(int a, int b)
+{
+    return a + b;
+}
+

src/tests/Interop/DllImportSearchPaths/NativeLibraryWithDependency/NativeLibraryWithDependency.cpp

@@ -0,0 +1,12 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#include <platformdefines.h>
+
+extern "C" int STDMETHODCALLTYPE Sum(int a, int b);
+
+extern "C" DLL_EXPORT int STDMETHODCALLTYPE CallDependencySum(int a, int b)
+{
+    return Sum(a, b);
+}
+