comctl32: Use strcmpW instead of pointer comparison to ensure treeview updates correctly

[Nikolay Sivov]

On 10/19/2014 18:44, Dan Bassi wrote:

> +    /* Old text is a null pointer due to HeapAlloc() failing, therefore unable to perform strcmpW so assume text has changed */
> +    if (!tiOld->pszText)
> +	return TRUE;
> +
I don't think you should necessary assume it's changed.

>       /* Text has changed and it's not a callback */
> -    if ((tvChange->mask & TVIF_TEXT) && (tiOld->pszText != tiNew->pszText) &&
> +    if ((tvChange->mask & TVIF_TEXT) && (strcmpW(tiOld->pszText, tiNew->pszText) != 0) &&
>   	tiNew->pszText != LPSTR_TEXTCALLBACKW)
>   	return TRUE;
This is wrong, you can't compare if it's a special callback value.

> +    originalItem.pszText = HeapAlloc(GetProcessHeap(), 0, originalItem.cchTextMax * sizeof(WCHAR));
Normally comctl32 code uses Alloc()/Free() functions.

This patch needs tests first, those tests should cover all possible 
combinations regarding callback cases, different pointers but same data,
same data but different pointers, maybe something else.