This commit adds support for compiling spew without the unsafe package.
When compiled without the unsafe package, some of the more advanced
features such as invoking stringers on pointers from non-pointer
variables and unexported struct fields are not available.
By default, spew will be compiled in the limited mode for Google App
Engine since the unsafe package is not available there. Additionally,
spew can be compiled without the unsafe package manually by specifying
the "disableunsafe" build tag.
Finally, a new package-level constant named "UnsafeDisabled" has been
exposed which can be used to programmatically determine if spew was
compiled with access to the unsafe package.
This commit adds tests for the recent cgo handling of char, unsigned char,
and uint8_t arrays.
In addition, it adds an architecture for the cgo specific testing based on
build constraints. This was done because spew itself does not require
cgo, but in order to test its handling of the cgo types it needs to be fed
cgo data. Rather than force all users to have a system which supports cgo
and an external compiler just to run the tests, the cgo test support must
explicitly be turned on via a build tag.
David Hill
Dave Collins
Josh Rickmar