* #797 possible leak on png error, returns from setjmp lost the row_pointers ref somehow
* skip that one using mingw until we have a reliable portable FP related tests suites (may never happpen)
We change the return type of `textLayout()` to `ssize_t`, and signal
failure by returning `-1`, so that laying out an empty string is no
longer handled as failure. We make sure that no overflow occurs,
assuming that all `int` values can be fully represented as `ssize_t`.
This makes it a bit cleaner when dealing with optional tests as we
use the LIST(APPEND...) command everywhere instead of sometimes SET
and sometimes LIST.
This makes it better match the autotools which makes it easier to
compare, and allows finer grain checks (since some subtests need
more than one feature test).
As an example, this makes it clear we were missing gdinterpolatedscale.
This makes the test code a lot easier to manage rather than copying &
pasting the same boiler plate multiple times.
Also take the opportunity to add a common prefix to each test name so
we don't get collisions between subdirs if a test happens to use the
same exact name.
Pierre Joye
Christoph M. Becker
wilson chen
willson-chen
Mike Frysinger
Nathanael Jones
Takeshi Abe
tabe