Description:
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OAuthProvider does not handle array parameters.

provider.c extracts GET and POST parameters but doesn't serializes arrays, so the signature that is generated for verification is invalid.


Expected result:
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Requesting http://www.example.com/?foo=bar&a[0]=33&a[1]=42&a[3]=stuff&b[0][aa]=bb&b[0][cc]=dd should build the parameter list including:

"foo" => "bar",
"a[0]" => "33",
"a[1]" => "42",
"a[3]" => "stuff",
"b[0][aa]" => "bb",
"b[0][cc]" => "dd"

and inject that into the base string, along with the OAuth parameters.

Actual result:
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Included parameter list is:

"foo" => "bar",
"a" => "Array",
"b" => "Array"