Just had this again in 1.2.3. Managed to prevent the crash by deleting and recreating the directory from within Thunar. Any other method caused it to still show up as a file. If I renamed the file on the command line, it would appear as a directory, then creating a new directory with the same name as before, it again appeared as a file. Looks like Thunar has some cache of information about files it's seen, and creating the directory from within Thunar got it to remove/update the invalid entry.
Just had this again in 1.2.3. Managed to prevent the crash by deleting and recreating the directory from within Thunar. Any other method caused it to still show up as a file. If I renamed the file on the command line, it would appear as a directory, then creating a new directory with the same name as before, it again appeared as a file. Looks like Thunar has some cache of information about files it's seen, and creating the directory from within Thunar got it to remove/update the invalid entry.