Update tests: port all to Catch2 2.8.0, removing old gtest

[rpavlik]

I was able to relatively quickly update most tests to Catch2, leaving behind the old version of catch entirely. I have also now done the last remaining gtest test (QuatExpMap) which became simpler when moved to Catch2, meaning that google test is no longer needed either and has been removed.

Builds on Debian Buster, tests pass except for test_fwd_headers which I'm pretty sure I didn't touch.

[rpavlik]

OK, I have now ported all the tests, so they should all build on MSVC2019 now too :)

[russell-taylor]

Compiles out of the box on Visual Studio 2019, even when OpenCV is not installed. Did not try installing Catch-22 to see if it also compiles in that case.

[russell-taylor]

When I run the tests, all but #6 QuatExpMap succeed. It fails. Here is its output:

$ ./QuatExpMap.exe

QuatExpMap.exe is a Catch v2.8.0 host application.
Run with -? for options

-----------------------------------------------------------------------------------------------------------------------
UnitQuatInput
  Basic quats
  Basic run ln
  Round trip
-----------------------------------------------------------------------------------------------------------------------
F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(173)
.......................................................................................................................

F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(177): FAILED:
  REQUIRE( q == exp_ln_q )
with expansion:
  [(0.70710678118654757                   0                   0), 0.70710678118654757]
  ==
  [(0.70710678118654757                   0                   0), 0.70710678118654746]
with messages:
  qCreator := Angle 1.5708, Axis 1 0 0
  q := [(0.70710678118654757                   0                   0), 0.70710678118654757]
  isIdentityQuat := false

-----------------------------------------------------------------------------------------------------------------------
UnitQuatInput
  Basic quats
  Basic run ln
  Round trip
-----------------------------------------------------------------------------------------------------------------------
F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(173)
.......................................................................................................................

F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(177): FAILED:
  REQUIRE( q == exp_ln_q )
with expansion:
  [(                  0 0.70710678118654757                   0), 0.70710678118654757]
  ==
  [(                  0 0.70710678118654757                   0), 0.70710678118654746]
with messages:
  qCreator := Angle 1.5708, Axis 0 1 0
  q := [(                  0 0.70710678118654757                   0), 0.70710678118654757]
  isIdentityQuat := false

-----------------------------------------------------------------------------------------------------------------------
UnitQuatInput
  Basic quats
  Basic run ln
  Round trip
-----------------------------------------------------------------------------------------------------------------------
F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(173)
.......................................................................................................................

F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(177): FAILED:
  REQUIRE( q == exp_ln_q )
with expansion:
  [(                  0                   0 0.70710678118654757), 0.70710678118654757]
  ==
  [(                  0                   0 0.70710678118654757), 0.70710678118654746]
with messages:
  qCreator := Angle 1.5708, Axis 0 0 1
  q := [(                  0                   0 0.70710678118654757), 0.70710678118654757]
  isIdentityQuat := false

-----------------------------------------------------------------------------------------------------------------------
UnitQuatInput
  Basic quats
  Basic run ln
  Round trip
-----------------------------------------------------------------------------------------------------------------------
F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(173)
.......................................................................................................................

F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(177): FAILED:
  REQUIRE( q == exp_ln_q )
with expansion:
  [(-0.70710678118654757                   -0                   -0), 0.70710678118654757]
  ==
  [(-0.70710678118654757                   -0                   -0), 0.70710678118654746]
with messages:
  qCreator := Angle -1.5708, Axis 1 0 0
  q := [(-0.70710678118654757                   -0                   -0), 0.70710678118654757]
  isIdentityQuat := false

-----------------------------------------------------------------------------------------------------------------------
UnitQuatInput
  Basic quats
  Basic run ln
  Round trip
-----------------------------------------------------------------------------------------------------------------------
F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(173)
.......................................................................................................................

F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(177): FAILED:
  REQUIRE( q == exp_ln_q )
with expansion:
  [(                  -0 -0.70710678118654757                   -0), 0.70710678118654757]
  ==
  [(                  -0 -0.70710678118654757                   -0), 0.70710678118654746]
with messages:
  qCreator := Angle -1.5708, Axis 0 1 0
  q := [(                  -0 -0.70710678118654757                   -0), 0.70710678118654757]
  isIdentityQuat := false

-----------------------------------------------------------------------------------------------------------------------
UnitQuatInput
  Basic quats
  Basic run ln
  Round trip
-----------------------------------------------------------------------------------------------------------------------
F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(173)
.......................................................................................................................

F:\tmp\src\OSVR-Core\tests\cplusplus\Util\QuatExpMap.cpp(177): FAILED:
  REQUIRE( q == exp_ln_q )
with expansion:
  [(                  -0                   -0 -0.70710678118654757), 0.70710678118654757]
  ==
  [(                  -0                   -0 -0.70710678118654757), 0.70710678118654746]
with messages:
  qCreator := Angle -1.5708, Axis 0 0 1
  q := [(                  -0                   -0 -0.70710678118654757), 0.70710678118654757]
  isIdentityQuat := false

=======================================================================================================================
test cases:   5 |   4 passed | 1 failed
assertions: 238 | 232 passed | 6 failed

[rpavlik]

That's interesting that the round-trips are close but not quite. I was getting exact here on Linux. However, I see I already made the other direction of round trip "approximate" (wrapping one endpoint in ApproxVec), so I'll try that with the quat one too. (ApproxQuat, in this case - these two were added by me but function equivalently to the Catch2 Approx() feature with doubles - basically a safe floating-point compare.)