Overlapping building placement possible

Using pysc2 I am able to produce the following game state:

In the real game, such a placement is not possible and would lead to the screen alert: Can't build, location invalid.

Here, in pysc2, the worker will in such a case be sent to the build location and then do nothing. So the building is not actually built on an invalid location.

Reproduce the overlapping building placement through pysc2 and compare it with the game's invalid-location behavior. Start by tracing how a build command is represented and handled for an overlapping location; no specific file or test is named in the issue. Done means the invalid placement is rejected instead of sending the worker to the location and leaving it idle.

Written by the indexing model from the issue text.