[core] avoid edges for labels that use text-variable-anchors

[pozdnyakov]

to prevent clipped labels in rendered image tiles.

Fixes https://github.com/mapbox/mapbox-gl-native-team/issues/90

[springmeyer]

This is missing a test. Can a test be added to the C++ test runner that ensures this is working as expected?

/cc @chloekraw

[springmeyer]

Coverage reporting indicates that this code is not covered by any tests currently:

https://codecov.io/gh/mapbox/mapbox-gl-native/compare/744102d95524f6ae3b451f9cfd726651008fcd6b...f8550b81b023d0fcb8b61ed9c2bdf794195b3dae/src/src/mbgl/text/placement.cpp#L166

/cc @mapbox/static-apis

[pozdnyakov]

This is missing a test. Can a test be added to the C++ test runner that ensures this is working as expected?

Working on it atm, the test will be added to the gl-js repo shortly

[springmeyer]

@pozdnyakov I'm noticing that the code in this PR is still uncovered in latest master: https://codecov.io/gh/mapbox/mapbox-gl-native/src/128da903c19c860e89be36bf67bd02cfa408a525/src/mbgl/text/placement.cpp#L167

Is that because mapbox-gl-native still needs to be updated to the latest mapbox-gl-js submodule version?

[pozdnyakov]

Is that because mapbox-gl-native still needs to be updated to the latest mapbox-gl-js submodule version?

Right, #15865 should fix it.

[springmeyer]

Oddly it doesn't. But maybe therefore I have the wrong expectations. I've been assuming that these lines would be covered:

But they still appear not to be with 8aaffd7 given: https://codecov.io/gh/mapbox/mapbox-gl-native/src/8aaffd71108117120652f45dba199d9c1dff2307/src/mbgl/text/placement.cpp#L166

[tmpsantos]

@springmeyer I think it is because we do not collect coverage from render tests.