Renaming a Formula
Sometimes software and formulae need to be renamed. To rename a formula you need to:

Rename the formula file and its class to a new formula. The new name must meet all the usual rules of formula naming. Fix any test failures that may occur due to the stricter requirements for new formulae than existing formulae (i.e.
brew audit strict
must pass for that formula). 
Create a pull request to the corresponding tap deleting the old formula file, adding the new formula file, and adding it to
formula_renames.json
with a commit message likenewack: renamed from ack
. Use the canonical name (e.g.ack
instead ofuser/repo/ack
).
A formula_renames.json
example for a formula rename:
{
"ack": "newack"
}