unit tests have lost heaps of coverage

[rade]

$ make SLOW=1 tests
ok      github.com/weaveworks/weave/ipam    361.039s    coverage: 17.7% of statements in github.com/weaveworks/weave/common, github.com/weaveworks/weave/common/docker, github.com/weaveworks/weave/ipam/paxos, github.com/weaveworks/weave/ipam/ring, github.com/weaveworks/weave/ipam/space, github.com/weaveworks/weave/net/address, github.com/weaveworks/weave/router
ok      github.com/weaveworks/weave/ipam/paxos  10.328s coverage: 0.1% of statements in github.com/weaveworks/weave/common, github.com/weaveworks/weave/router
ok      github.com/weaveworks/weave/ipam/ring   11.042s coverage: 1.8% of statements in github.com/weaveworks/weave/common, github.com/weaveworks/weave/net/address, github.com/weaveworks/weave/router
ok      github.com/weaveworks/weave/ipam/space  0.012s  coverage: 25.3% of statements in github.com/weaveworks/weave/common, github.com/weaveworks/weave/net/address
ok      github.com/weaveworks/weave/nameserver  12.444s coverage: 1.1% of statements in github.com/weaveworks/weave/common, github.com/weaveworks/weave/common/docker, github.com/weaveworks/weave/net/address, github.com/weaveworks/weave/router
ok      github.com/weaveworks/weave/net 0.012s  coverage: 3.0% of statements
ok      github.com/weaveworks/weave/proxy   0.975s  coverage: 0.0% of statements in github.com/weaveworks/weave/common, github.com/weaveworks/weave/common/docker, github.com/weaveworks/weave/nameserver, github.com/weaveworks/weave/net/address, github.com/weaveworks/weave/router
ok      github.com/weaveworks/weave/router  1.693s  coverage: 3.0% of statements in github.com/weaveworks/weave/common
total:                              (statements)    15.3%

I'm not that worried about the % figures, but note that the "of statements in" is missing some directories, like weave/ipam in the ipam tests ,and weave/nameserver in the nameserver tests. i.e. it appears to be missing coverage on the package containing the test.