Unit/integration tests are run in 2 steps.
First step: execute the plugin in Composer
cd tests/
./run.sh
This will run the integration tests (i.e. this will run the Composer plugin for real, inside Composer)
Second step: run unit tests
cd ..
vendor/bin/phpunit
Note: you must run the integration tests before the unit tests. Indeed, the integration tests are generating PHP files and classes that will be later tested by the unit tests.
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