add more route tests

[finnhodgkin]

relates to #7

[codecov-io]

Codecov Report

Merging #48 into master will decrease coverage by 1.16%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #48      +/-   ##
==========================================
- Coverage   69.79%   68.62%   -1.17%     
==========================================
  Files           4        4              
  Lines          96      102       +6     
  Branches       18       21       +3     
==========================================
+ Hits           67       70       +3     
- Misses         29       32       +3

Impacted Files	Coverage Δ
src/router.js	93.33% <ø> (ø)	⬆️
src/handler.js	61.29% <ø> (-1.21%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update d0ded49...9cecddf. Read the comment docs.