composer/tests/Composer/Test/Fixtures/installer/install-branch-alias-composer-repo/packages.json

{
    "packages": {
        "a/a": {
            "dev-foobar": {
                "name": "a/a",
                "version": "dev-foobar",
                "version_normalized": "dev-foobar",
                "source": {
                    "type": "git",
                    "url": "git@example.com:repo.git",
                    "reference": "abcdef0000000000000000000000000000000000"
                },
                "time": "2014-11-13 11:52:12",
                "type": "library",
                "extra": {
                    "branch-alias": {
                        "dev-foobar": "3.2.x-dev"
                    }
                }
            }
        }
    }
}