Hello,
I have a package depending on another:

Foo/stack.yaml:

flags: {}
packages:
- '.'
- location: ../Bar
  extra-dep: true
extra-deps:
- Bar-0.7.6
resolver: lts-2.19

When I compile (stack build), I obtain:

--  While attempting to add dependency,
    Could not find package DebugTraceHelpers in known packages

--  Failure when adding dependencies:   
      DebugTraceHelpers: needed (==0.12.*), but not present in build plan, latest is 0.12
    needed for package: Bar-0.7.6

I find it strange that it asks for DebugTraceHelpers because it's not a direct dependency of my package, but a dependency of a dependency.
It is correctly mentioned in Bar/stack.yml:

flags: {}
packages:
- '.'
extra-deps:
- DebugTraceHelpers-0.12
resolver: lts-2.19