change error message to be more human readable

[christophertull]

No description provided.

[codecov-io]

Codecov Report

Merging #16 into master will decrease coverage by 1.5%.
The diff coverage is 33.33%.

@@            Coverage Diff             @@
##           master      #16      +/-   ##
==========================================
- Coverage   92.26%   90.76%   -1.51%     
==========================================
  Files           2        2              
  Lines         194      184      -10     
==========================================
- Hits          179      167      -12     
- Misses         15       17       +2

Impacted Files	Coverage Δ
R/tier_calcs.R	93.54% <33.33%> (-6.46%)	⬇️
R/rateParser.R	89.34% <0%> (+0.37%)	⬆️

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[patwater]

@christophertull is this an automated tool you deployed? Looks fancy

[christophertull]

Yep. After each push / merge Travis runs the unit tests that I added and reports on the status of passed/failed tests. CodeCov checks what percentage of code is "covered by" (i.e. touched during the execution of) these unit tests. It is giving me red X's because I added new code without adding a test to test this new code. Therefore the percentage of code coverage has decreased.