Travic CI build stage for php 7.2 with `coverage=1 lint=1` fails

[baspeeters]

Travis CI build for php 7.2 with coverage=1 lint=1 fails when executing ./bin/compile at the end of the script stage:

+php schema.phar generate-types tmp/ tests/e2e/schema.yml
[warning] The property "address" (type "Person") has several types.
Using the first one ("PostalAddress") or possible
options("PostalAddress", "Text").
PHP Fatal error:  Uncaught Error: Class
'_HumbugBoxefddd8a7b673\Twig\TwigTest' not found in
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/Extension/CoreExtension.php:129
Stack trace:
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/ExtensionSet.php(309):
_HumbugBoxefddd8a7b673\Twig\Extension\CoreExtension->getTests()
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/ExtensionSet.php(296):
_HumbugBoxefddd8a7b673\Twig\ExtensionSet->initExtension(Object(_HumbugBoxefddd8a7b673\Twig\Extension\CoreExtension))
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/ExtensionSet.php(275):
_HumbugBoxefddd8a7b673\Twig\ExtensionSet->initExtensions()
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/Environment.php(442):
_HumbugBoxefddd8a7b673\Twig\ExtensionSet->getUnaryOperators()
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/Extension/CoreExtension.php
on line 129
Fatal error: Uncaught Error: Class
'_HumbugBoxefddd8a7b673\Twig\TwigTest' not found in
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/Extension/CoreExtension.php:129
Stack trace:
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/ExtensionSet.php(309):
_HumbugBoxefddd8a7b673\Twig\Extension\CoreExtension->getTests()
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/ExtensionSet.php(296):
_HumbugBoxefddd8a7b673\Twig\ExtensionSet->initExtension(Object(_HumbugBoxefddd8a7b673\Twig\Extension\CoreExtension))
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/ExtensionSet.php(275):
_HumbugBoxefddd8a7b673\Twig\ExtensionSet->initExtensions()
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/Environment.php(442):
_HumbugBoxefddd8a7b673\Twig\ExtensionSet->getUnaryOperators()
phar:///home/travis/build/baspeeters/schema-generator/schema.phar/vendor/twig/twig/src/Extension/CoreExtension.php
on line 129
The command "if [[ ! $deps && $TRAVIS_PHP_VERSION = "7.2" ]]; then cp
composer.json build/schema-generator/ composer
--working-dir=build/schema-generator dump-autoload
--classmap-authoritative --no-dev; ./bin/compile; fi" exited with 255.

Example build: https://travis-ci.org/api-platform/schema-generator/jobs/541147735