Index: apitests/shell32/CMakeLists.txt
===================================================================
--- apitests/shell32/CMakeLists.txt	(revision 70407)
+++ apitests/shell32/CMakeLists.txt	(working copy)
@@ -8,7 +8,7 @@
     CShellDesktop.cpp
     menu.cpp
     testlist.c)
-target_link_libraries(shell32_apitest wine uuid)
+target_link_libraries(shell32_apitest wine uuid ${PSEH_LIB})
 set_module_type(shell32_apitest win32cui)
 add_importlibs(shell32_apitest user32 gdi32 shell32 ole32 oleaut32 shlwapi msvcrt kernel32)
 add_cd_file(TARGET shell32_apitest DESTINATION reactos/bin FOR all)
Index: apitests/shell32/CShellDesktop.cpp
===================================================================
--- apitests/shell32/CShellDesktop.cpp	(revision 70407)
+++ apitests/shell32/CShellDesktop.cpp	(working copy)
@@ -49,6 +49,71 @@
     ok(psv != psv_2, "Expected %p != %p\n", static_cast<PVOID>(psv), static_cast<PVOID>(psv_2));
 }
 
+static void TestCompareGuarded(IShellFolder* psf, LPITEMIDLIST desktop)
+{
+    HRESULT hr = S_OK;
+    _SEH2_TRY
+    {
+        hr = psf->CompareIDs(0, desktop, NULL);
+        ok(hr == E_INVALIDARG, "hr = %lx\n", hr);
+        hr = psf->CompareIDs(0, NULL, desktop);
+        ok(hr == E_INVALIDARG, "hr = %lx\n", hr);
+        hr = psf->CompareIDs(0, desktop, desktop);
+        ok(hr == S_EQUAL, "hr = %lx\n", hr);
+    }
+    _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
+    {
+        hr = E_ABORT;
+    }
+    _SEH2_END;
+    ok(hr != E_ABORT, "hr = %lx\n", hr);
+}
+
+// We would normally use S_LESSTHAN and S_GREATERTHAN, but w2k3 returns numbers like 3 and -3...
+#define IS_LESSTAN(hr)  (((hr) & 0x8000) && SUCCEEDED(hr))
+#define IS_GREATERTHAN(hr)  ((!((hr) & 0x8000))  && SUCCEEDED(hr))
+
+static
+VOID
+TestCompareIDList(IShellFolder* psf)
+{
+    HRESULT hr = psf->CompareIDs(0, NULL, NULL);
+    ok(hr == E_INVALIDARG, "hr = %lx\n", hr);
+
+    CComHeapPtr<ITEMIDLIST> desktop(SHCloneSpecialIDList(NULL, CSIDL_DESKTOP, TRUE));
+    TestCompareGuarded(psf, desktop);
+
+    CComHeapPtr<ITEMIDLIST> internet(SHCloneSpecialIDList(NULL, CSIDL_INTERNET, TRUE));
+    hr = psf->CompareIDs(0, internet, desktop);
+    ok(IS_LESSTAN(hr), "hr = %lx\n", hr);
+    hr = psf->CompareIDs(0, desktop, internet);
+    ok(IS_GREATERTHAN(hr), "hr = %lx\n", hr);
+
+    CComHeapPtr<ITEMIDLIST> programs(SHCloneSpecialIDList(NULL, CSIDL_PROGRAMS, TRUE));
+    hr = psf->CompareIDs(0, programs, desktop);
+    ok(IS_LESSTAN(hr), "hr = %lx\n", hr);
+    hr = psf->CompareIDs(0, desktop, programs);
+    ok(IS_GREATERTHAN(hr), "hr = %lx\n", hr);
+    hr = psf->CompareIDs(0, internet, programs);
+    ok(IS_GREATERTHAN(hr), "hr = %lx\n", hr);
+    hr = psf->CompareIDs(0, programs, internet);
+    ok(IS_LESSTAN(hr), "hr = %lx\n", hr);
+
+    CComPtr<IPersistFolder2> persist;
+    hr = psf->QueryInterface(IID_PPV_ARG(IPersistFolder2, &persist));
+    ok(hr == S_OK, "hr = %lx\n", hr);
+    if (hr == S_OK)
+    {
+        CComHeapPtr<ITEMIDLIST> cur;
+        hr = persist->GetCurFolder(&cur);
+        ok(hr == S_OK, "hr = %lx\n", hr);
+        hr = psf->CompareIDs(0, cur, desktop);
+        ok(hr == S_EQUAL, "hr = %lx\n", hr);
+        hr = psf->CompareIDs(0, desktop, cur);
+        ok(hr == S_EQUAL, "hr = %lx\n", hr);
+    }
+}
+
 START_TEST(CShellDesktop)
 {
     HRESULT hr;
@@ -83,4 +148,5 @@
     ok(psf == static_cast<IShellFolder *>(psf2), "Expected %p == %p\n", static_cast<PVOID>(psf), static_cast<PVOID>(psf2));
 
     TestShellFolder(psf2);
+    TestCompareIDList(psf);
 }