@Test
    void verifyClientSecretFromEnvironment() {
        val secret = applicationContext.getEnvironment().getProperty("app.custom.secret");
        val registeredService = new OAuthRegisteredService();
        registeredService.setClientId("clientid");
        registeredService.setClientSecret("${#applicationContext.get().environment.getProperty('app.custom.secret')}");
        val result = oauth20ClientSecretValidator.validate(registeredService, secret);
        assertTrue(result);
    }
This is {@link DefaultOAuth20ClientSecretValidatorTests}.

@author Misagh Moayyed
@since 6.6.0
support/cas-server-support-oauth/src/test/java/org/apereo/cas/support/oauth/validator/DefaultOAuth20ClientSecretValidatorTests.java