stack's ghci command breaks importing from the current directory.

~/code/stack-bug $ ghci
GHCi, version 7.10.3: http://www.haskell.org/ghc/  :? for help
λ> :l Foo
[1 of 2] Compiling Bar              ( Bar.hs, interpreted )
[2 of 2] Compiling Foo              ( Foo.hs, interpreted )
Ok, modules loaded: Foo, Bar.
λ> 
Leaving GHCi.
~/code/stack-bug $ stack ghci
Configuring GHCi with the following packages: 
GHCi, version 7.10.3: http://www.haskell.org/ghc/  :? for help
λ> :l Foo

Foo.hs:3:8:
    Could not find module ‘Bar’
    Perhaps you meant
      Bag (needs flag -package-key ghc-7.10.3)
      Var (needs flag -package-key ghc-7.10.3)
Failed, modules loaded: none.
λ> 

---

Thanks to Christopher Allen for pointing the way towards a fix.

You can work around the bug by re-including the current directory:

$ stack ghci --ghci-options -i.