Foamgrid tests can't pass because of unapplicable "sum of outernormals = 0" test (from dune-grid)

I tried to run the tests for dune-foamgrid and noticed this too.

But shouldn't the sum of outer normals still be zero even when summing the outer normals of a square embedded into a 3d space? Or lines embedded in a 2d- or 3d-space?

There are also other tests that fail later if one skips past the failing sum-of-normals test.

It should pass if the surface is not curved or bifurcated. For bifurcations the problem is that there is more than one intersection and the normals are added up.

For me all tests pass if the sum-of-normals test is skipped. Which test fails for you?

I opened core/dune-grid!332 (merged) to fix this.

mentioned in merge request !58 (merged)

assigned to @tkoch

closed via merge request !58 (merged)

mentioned in commit 4a2cadc0