composer require g4/code-coverage

./vendor/bin/phpunit --coverage-clover=path/to/code-coverage.xml

usage: code-coverage [<options>]

Analyze phpunit coverage report.

OPTIONS
  --file, -f         Path to phpunit's code coverage xml report
  --help, -?         Display this help.
  --percentage, -p   Minimum coverage percentage to be considered "highly"
                     covered.

e.g.
./vendor/bin/code-coverage -p 90 -f path/to/code-coverage.xml

output:
 Required:     90.00%
   Methods:    91.43%
   Statements: 95.58%
   Elements:   94.59%