Base64 urlsafe_decode64 unsafe use of tr.
A lot of the base64 module lacks duck typing or nice errors.
For example the
urlsafe_decode64 function never checks
str is something that behaves like a string and will respond to
If you pass
nil by mistake you end up with the dreaded "can't call method on (n)" rather than an informative error.
def urlsafe_decode64(str) # NOTE: RFC 4648 does say nothing about unpadded input, but says that # "the excess pad characters MAY also be ignored", so it is inferred that # unpadded input is also acceptable. str = str.tr("-_", "+/") if !str.end_with?("=") && str.length % 4 != 0 str = str.ljust((str.length + 3) & ~3, "=") end strict_decode64(str) end
Raising an error or silently failing if the argument doesn't respond to
to_s.tr) both seem preferable to errors raised by the internal implementation but I'm wondering if there is a preferred approach in Rubys stdlib?
Updated by jeremyevans0 (Jeremy Evans) about 1 year ago
- Status changed from Open to Rejected
I don't think this is a bug. Most pure Ruby code assumes and does not check that method arguments respond to all methods that the code expects them to respond to. It's generally considered a smell to take code like:
def foo(bar, baz) bar.x + baz.y end
and change it to:
def foo(bar, baz) raise ArgumentError, "bar does not respond to x" unless bar.respond_to?(:x) raise ArgumentError, "baz does not respond to y" unless baz.respond_to?(:y) bar.x + baz.y end
baz could be instances of subclasses of BasicObject and not Object with the
y methods defined, respectively.