This extends py::vectorize to automatically pass through
non-vectorizable arguments. This removes the need for the documented
"explicitly exclude an argument" workaround.
Vectorization now applies to arithmetic, std::complex, and POD types,
passed as plain value or by const lvalue reference (previously only
pass-by-value types were supported). Non-const lvalue references and
any other types are passed through as-is.
Functions with rvalue reference arguments (whether vectorizable or not)
are explicitly prohibited: an rvalue reference is inherently not
something that can be passed multiple times and is thus unsuitable to
being in a vectorized function.
The vectorize returned value is also now more sensitive to inputs:
previously it would return by value when all inputs are of size 1; this
is now amended to having all inputs of size 1 *and* 0 dimensions. Thus
if you pass in, for example, [[1]], you get back a 1x1, 2D array, while
previously you got back just the resulting single value.
Vectorization of member function specializations is now also supported
via `py::vectorize(&Class::method)`; this required passthrough support
for the initial object pointer on the wrapping function pointer.
This extends the trivial handling to support trivial handling for
Fortran-order arrays (i.e. column major): if inputs aren't all
C-contiguous, but *are* all F-contiguous, the resulting array will be
F-contiguous and we can do trivial processing.
For anything else (e.g. C-contiguous, or inputs requiring non-trivial
processing), the result is in (numpy-default) C-contiguous layout.
The only part of the vectorize code that actually needs c-contiguous is
the "trivial" broadcast; for non-trivial arguments, the code already
uses strides properly (and so handles C-style, F-style, neither, slices,
etc.)
This commit rewrites `broadcast` to additionally check for C-contiguous
storage, then takes off the `c_style` flag for the arguments, which
will keep the functionality more or less the same, except for no longer
requiring an array copy for non-c-contiguous input arrays.
Additionally, if we're given a singleton slice (e.g. a[0::4, 0::4] for a
4x4 or smaller array), we no longer fail triviality because the trivial
code path never actually uses the strides on a singleton.
With this change both C++ and Python write to sys.stdout which resolves
the capture issues noted in #351. Therefore, the related workarounds are
removed.
Adding or removing tests is a little bit cumbersome currently: the test
needs to be added to CMakeLists.txt, the init function needs to be
predeclared in pybind11_tests.cpp, then called in the plugin
initialization. While this isn't a big deal for tests that are being
committed, it's more of a hassle when working on some new feature or
test code for which I temporarily only care about building and linking
the test being worked on rather than the entire test suite.
This commit changes tests to self-register their initialization by
having each test initialize a local object (which stores the
initialization function in a static variable). This makes changing the
set of tests being build easy: one only needs to add or comment out
test names in tests/CMakeLists.txt.
A couple other minor changes that go along with this:
- test_eigen.cpp is now included in the test list, then removed if eigen
isn't available. This lets you disable the eigen tests by commenting
it out, just like all the other tests, but keeps the build working
without eigen eigen isn't available. (Also, if it's commented out, we
don't even bother looking for and reporting the building with/without
eigen status message).
- pytest is now invoked with all the built test names (with .cpp changed
to .py) so that it doesn't try to run tests that weren't built.
The C++ part of the test code is modified to achieve this. As a result,
this kind of test:
```python
with capture:
kw_func1(5, y=10)
assert capture == "kw_func(x=5, y=10)"
```
can be replaced with a simple:
`assert kw_func1(5, y=10) == "x=5, y=10"`
Use simple asserts and pytest's powerful introspection to make testing
simpler. This merges the old .py/.ref file pairs into simple .py files
where the expected values are right next to the code being tested.
This commit does not touch the C++ part of the code and replicates the
Python tests exactly like the old .ref-file-based approach.
