File::isAccessable

[tristanlins]

@see #60 (comment)

The accessability differ between files and directories (in a unix permission environment).

A file is accessable if it is readable.
A directory is accessable if it is executeable and readable (for content listing).

How about add a convenience method File::isAccessable:

class File::isAccessable {
    public function isAccessable() {
        if ($this->isFile()) {
            return $this->isReadable();
        }
        else if ($this->isDirectory()) {
            return $this->isExecuteable() && $this->isReadable();
        }
    }
}

According to #49 this may be extracted to the permission interface, to allow the permission manager check the accessablility.

[backbone87]

What is the behavior in unix for:

• Directories that are only readable
• Directories that are only executeable

Without the answers for mentioned questions my current point would be to let be "isReadable" and "isExecuteable" to be synonymous for directories.

[tristanlins]

Directories that are only readable are not accessable -> false
Directories that are only executeable can be accessed, but not readed -> false

In other word, isAccessable will only return true if the target can be read. For directories this means, it have also be executeable.

[discordier]

IMO we should drop this method altogether in favor of:

class File {
    public function isListable() {
        if ($this->isFile()) {
            return false;
        }
        else if ($this->isDirectory()) {
            return $this->isExecuteable() && $this->isReadable();
        }
    }
}