imm32: Fix ImmGetDescription behavior with a null HKL.

dlls/imm32/imm.c

@@ -1523,6 +1523,8 @@ UINT WINAPI ImmGetDescriptionA(
 
   /* find out how many characters in the unicode buffer */
   len = ImmGetDescriptionW( hKL, NULL, 0 );
+  if (!len)
+    return 0;
 
   /* allocate a buffer of that size */
   buf = HeapAlloc( GetProcessHeap(), 0, (len + 1) * sizeof (WCHAR) );
@@ -1550,6 +1552,7 @@ UINT WINAPI ImmGetDescriptionW(HKL hKL, LPWSTR lpszDescription, UINT uBufLen)
 
   FIXME("(%p, %p, %d): semi stub\n", hKL, lpszDescription, uBufLen);
 
+  if (!hKL) return 0;
   if (!uBufLen) return lstrlenW( name );
   lstrcpynW( lpszDescription, name, uBufLen );
   return lstrlenW( lpszDescription );

dlls/imm32/tests/imm32.c

@@ -629,18 +629,19 @@ static void test_ImmGetContext(void)
 static void test_ImmGetDescription(void)
 {
     HKL hkl;
-    WCHAR japime[] = { 'E', '0', '0', '1', '0', '4', '1', '1', 0 };
     WCHAR descW[100];
     CHAR descA[100];
     UINT ret, lret;
 
     /* FIXME: invalid keyboard layouts should not pass */
     ret = ImmGetDescriptionW(NULL, NULL, 0);
-    todo_wine ok(!ret, "ImmGetDescriptionW failed, expected 0 received %d.\n", ret);
+    ok(!ret, "ImmGetDescriptionW failed, expected 0 received %d.\n", ret);
+    ret = ImmGetDescriptionA(NULL, NULL, 0);
+    ok(!ret, "ImmGetDescriptionA failed, expected 0 received %d.\n", ret);
 
     /* load a language with valid IMM descriptions */
-    hkl = LoadKeyboardLayoutW(japime, KLF_ACTIVATE);
-    todo_wine ok(hkl != 0, "LoadKeyboardLayoutW failed, expected != 0.\n");
+    hkl = GetKeyboardLayout(0);
+    ok(hkl != 0, "GetKeyboardLayout failed, expected != 0.\n");
 
     ret = ImmGetDescriptionW(hkl, NULL, 0);
     if(!ret)
@@ -649,6 +650,12 @@ static void test_ImmGetDescription(void)
         return;
     }
 
+    SetLastError(0xdeadcafe);
+    ret = ImmGetDescriptionW(0, NULL, 100);
+    ok (ret == 0, "ImmGetDescriptionW with 0 hkl should return 0\n");
+    ret = GetLastError();
+    ok (ret == 0xdeadcafe, "Last Error should remain unchanged\n");
+
     ret = ImmGetDescriptionW(hkl, descW, 0);
     ok(ret, "ImmGetDescriptionW failed, expected != 0 received 0.\n");