patch with tag collision test

[jycor]

Tag collisions exists and can lead to false positives.

[coffeegoddd]

@jycor DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
1eefa4c	ok	5937457

version	total_tests
1eefa4c	5937457

correctness_percentage
100.0