Existence Invariants

[bbengfort]

Adds existence invariants to writes, e.g. requiring that the object does not exist before a write (create, delete check?) or that it does exist before a write (update, ensure delete).

[codecov]

Codecov Report

Merging #27 (bd1ff51) into main (9966c0c) will decrease coverage by 0.07%.
The diff coverage is 48.64%.

❗ Current head bd1ff51 differs from pull request most recent head ec0c2c9. Consider uploading reports for the commit ec0c2c9 to get more accurate results

@@            Coverage Diff             @@
##             main      #27      +/-   ##
==========================================
- Coverage   57.83%   57.77%   -0.07%     
==========================================
  Files          10       10              
  Lines         574      611      +37     
==========================================
+ Hits          332      353      +21     
- Misses        195      209      +14     
- Partials       47       49       +2     

Files Changed	Coverage Δ
options/options.go	74.35% <0.00%> (-19.19%)	⬇️
engines/leveldb/leveldb.go	82.65% <46.15%> (-5.59%)	⬇️
honu.go	51.09% <75.00%> (+4.11%)	⬆️