When running unit tests, output coverage for imported modules.

test/units.sh

@@ -32,8 +32,9 @@ for dir in $TESTDIRS; do
 
     GO_TEST_ARGS_RUN="$GO_TEST_ARGS"
     if [ -n "$SLOW" ]; then
+        COVERPKGS=$(go list -f '{{join .Deps "\n"}}' $dir | grep "weaveworks" | paste -s -d,)
         output=$(mktemp $coverdir/unit.XXXXXXXXXX)
-        GO_TEST_ARGS_RUN="$GO_TEST_ARGS -coverprofile=$output"
+        GO_TEST_ARGS_RUN="$GO_TEST_ARGS -coverprofile=$output -coverpkg=$COVERPKGS"
     fi
 
     START=$(date +%s)