schema for matrix

[skshetry]

See iterative/dvc#9725.

[dberenbaum]

Why is it an entirely new class/type of Stage instead of adding a matrix attribute to the existing Stage (similar to cmd, deps, etc.)?

[skshetry]

Semantically, Stage definition is not the same as a Matrix, it is a superset.

stages:
  stage1:
    matrix:
      ...

    <...Stage>

Also take foreach for example. The do part is a Stage definition which does not support matrix. Again, it's an internal code organization thing, which does not have any impact to users, they care about the Definition.

dvcyaml-schema/gen.py

Line 319 in 2f5056c

Definition = ForeachDo | Matrix | Stage

[daavoo]

Just for completeness, it might be good adding items to examples/invalid, i.e. mixing foreach and matrix