If any v1 configs are present, global-level v2 var declarations do not work

[beckjake]

Describe the bug

If you have some v2 project configs with global-level var declarations, adding any project with a v1 config breaks them.

Steps To Reproduce

Create 3 projects:

• two with v2 configs and global var declarations
• one with a v1 config

Even if the third project never accesses any vars from the v2 configs and vice-versa, dbt will convert the v2 configs into v1 configs and lose the global level vars.

I have a few test cases to exercise this behavior that I'll add with the fix, but I think basically that this:

vars:
  my_var: 1000

should become (repeated for seeds/snapshots, too)

models:
  project_1:
    vars:
      my_var: 1000
  project_2:
    vars:
      my_var: 1000
...

Which can then be overridden with any actual existing per-project config members.

Expected behavior

dbt should include make any global v2 vars available as a project-level config for each dependency and the root project.

System information

Any databases, any OS, any supported python, dbt==0.17.0rc1

[drewbanin]

closed by #2477