ole32: Fix CommonPrefixWith() for antimoniker, when other is also antimoniker.

dlls/ole32/antimoniker.c

@@ -400,25 +400,32 @@ AntiMonikerImpl_Inverse(IMoniker* iface,IMoniker** ppmk)
 /******************************************************************************
  *        AntiMoniker_CommonPrefixWith
  ******************************************************************************/
-static HRESULT WINAPI
-AntiMonikerImpl_CommonPrefixWith(IMoniker* iface,IMoniker* pmkOther,IMoniker** ppmkPrefix)
+static HRESULT WINAPI AntiMonikerImpl_CommonPrefixWith(IMoniker *iface, IMoniker *other, IMoniker **prefix)
 {
-    DWORD mkSys;
-
-    IMoniker_IsSystemMoniker(pmkOther,&mkSys);
-
-    if(mkSys==MKSYS_ANTIMONIKER){
-
-        IMoniker_AddRef(iface);
-
-        *ppmkPrefix=iface;
+    AntiMonikerImpl *moniker = impl_from_IMoniker(iface), *other_moniker;
+    HRESULT hr;
 
-        IMoniker_AddRef(iface);
+    TRACE("%p, %p, %p.\n", iface, other, prefix);
 
-        return MK_S_US;
+    other_moniker = unsafe_impl_from_IMoniker(other);
+    if (other_moniker)
+    {
+        if (moniker->count <= other_moniker->count)
+        {
+            *prefix = iface;
+            hr = moniker->count == other_moniker->count ? MK_S_US : MK_S_ME;
+        }
+        else
+        {
+            *prefix = other;
+            hr = MK_S_HIM;
+        }
+
+        IMoniker_AddRef(*prefix);
+        return hr;
     }
-    else
-        return MonikerCommonPrefixWith(iface,pmkOther,ppmkPrefix);
+
+    return MonikerCommonPrefixWith(iface, other, prefix);
 }
 
 /******************************************************************************

dlls/ole32/tests/moniker.c

@@ -2430,8 +2430,6 @@ todo_wine
     hr = IMoniker_IsEqual(moniker, NULL);
     ok(hr == E_INVALIDARG, "Unexpected hr %#x.\n", hr);
 
-    IStream_Release(stream);
-
     /* Reduce() */
     hr = IMoniker_Reduce(moniker, NULL, MKRREDUCE_ALL, NULL, &reduced);
     ok(hr == MK_S_REDUCED_TO_SELF, "Unexpected hr %#x.\n", hr);
@@ -2453,6 +2451,70 @@ todo_wine
 todo_wine
     ok(hr == E_INVALIDARG, "Unexpected hr %#x.\n", hr);
 
+    /* CommonPrefixWith() */
+    stream_write_dword(stream, 0);
+
+    hr = IMoniker_Load(moniker, stream);
+    ok(hr == S_OK, "Unexpected hr %#x.\n", hr);
+
+    hr = IMoniker_CommonPrefixWith(moniker, moniker2, &moniker3);
+    ok(hr == MK_S_ME, "Unexpected hr %#x.\n", hr);
+    ok(moniker3 == moniker, "Unexpected prefix moniker.\n");
+    IMoniker_Release(moniker3);
+
+    hr = IMoniker_CommonPrefixWith(moniker2, moniker, &moniker3);
+    ok(hr == MK_S_HIM, "Unexpected hr %#x.\n", hr);
+    ok(moniker3 == moniker, "Unexpected prefix moniker.\n");
+    IMoniker_Release(moniker3);
+
+    stream_write_dword(stream, 10);
+
+    hr = IMoniker_Load(moniker, stream);
+    ok(hr == S_OK, "Unexpected hr %#x.\n", hr);
+
+    stream_write_dword(stream, 5);
+
+    hr = IMoniker_Load(moniker2, stream);
+    ok(hr == S_OK, "Unexpected hr %#x.\n", hr);
+
+    hr = IMoniker_CommonPrefixWith(moniker, moniker2, &moniker3);
+    ok(hr == MK_S_HIM, "Unexpected hr %#x.\n", hr);
+    ok(moniker3 == moniker2, "Unexpected prefix moniker.\n");
+    IMoniker_Release(moniker3);
+
+    hr = IMoniker_CommonPrefixWith(moniker2, moniker, &moniker3);
+    ok(hr == MK_S_ME, "Unexpected hr %#x.\n", hr);
+    ok(moniker3 == moniker2, "Unexpected prefix moniker.\n");
+    IMoniker_Release(moniker3);
+
+    /* Now same length, 0 or 2 */
+    stream_write_dword(stream, 0);
+    hr = IMoniker_Load(moniker, stream);
+    ok(hr == S_OK, "Unexpected hr %#x.\n", hr);
+
+    stream_write_dword(stream, 0);
+    hr = IMoniker_Load(moniker2, stream);
+    ok(hr == S_OK, "Unexpected hr %#x.\n", hr);
+
+    hr = IMoniker_CommonPrefixWith(moniker, moniker2, &moniker3);
+    ok(hr == MK_S_US, "Unexpected hr %#x.\n", hr);
+    ok(moniker3 == moniker, "Unexpected prefix moniker.\n");
+    IMoniker_Release(moniker3);
+
+    stream_write_dword(stream, 2);
+    hr = IMoniker_Load(moniker, stream);
+    ok(hr == S_OK, "Unexpected hr %#x.\n", hr);
+
+    stream_write_dword(stream, 2);
+    hr = IMoniker_Load(moniker2, stream);
+    ok(hr == S_OK, "Unexpected hr %#x.\n", hr);
+
+    hr = IMoniker_CommonPrefixWith(moniker, moniker2, &moniker3);
+    ok(hr == MK_S_US, "Unexpected hr %#x.\n", hr);
+    ok(moniker3 == moniker, "Unexpected prefix moniker.\n");
+    IMoniker_Release(moniker3);
+
+    IStream_Release(stream);
     IBindCtx_Release(bindctx);
     IMoniker_Release(moniker);
     IMoniker_Release(moniker2);