Write tests for the new router.ProcManager structure.

[evanlinjin]

Branch: mainnet-dev

Prerequisites

1. Move genMockApp() from test file of /pkg/app module to /pkg/app/apptest: https://github.com/skycoin/skywire/blob/64860b09f102a34d78b6eae80efcaa5d7c7cba66/pkg/app/executor_test.go#L29-L49

2. Create an empty implementation of router.Router.

Tests

• RunProc() should:

  • Fail if input c.BinLoc is invalid.
  • Succeed succeed if all other inputs are valid.
  • Not assign a port if input port=0.
  • After calling RunProc(), the returned *AppProc should:
    • Have ProcID() return 1 on first process, 2 in second, etc.
    • Have Stopped() return false.
    • After calling Stop(), should return no error and Stopped() should then return true.

• Proc() should return the right *AppProc of given ProcID, and should return false if:

  • RunProc never returned such a ProcID.
  • AppProc is stopped.

• AllocPort() should always return free ports.

• ProcOfPort() should return proc assigned to given port only if proc is still running (not .Stopped()).

• RangeProcIDs() and RangePorts() should cover all that is expected.

• Close() should succeed.

[evanlinjin]

@ivcosla I've started work on this. I finished implementing two tests and wrote barebones and comments for subsequent tests to be written.

Please refer to PR: #317