title: How to enable Spring's auto-configuration report in tests?
body: <p>I just found out that Spring has a debug mode, which gives insights on the auto-configuration. For a server, it can be enabled by passing <code>--debug</code> as an application parameter.</p>
  
  <p><strong>Is there a way to enable the debug mode also for tests (executed with the <code>SpringJUnit4ClassRunner</code>)?</strong></p>
  
  <hr>
  
  <p>If the auto-configuration report is working, it should print some output like this:</p>
  
  <pre><code>=========================
  AUTO-CONFIGURATION REPORT
  =========================
  
  
  Positive matches:
  -----------------
  
     ConfigServiceBootstrapConfiguration#configServicePropertySource matched
        - matched (OnPropertyCondition)
  
     ConfigurationPropertiesRebinderAutoConfiguration matched
        - @ConditionalOnBean (types: org.springframework.boot.context.properties.ConfigurationPropertiesBindingPostProcessor; SearchStrategy: all) found the following [org.springframework.boot.context.properties.ConfigurationPropertiesBindingPostProcessor] (OnBeanCondition)
  
     ConfigurationPropertiesRebinderAutoConfiguration#configurationPropertiesBeans matched
        - @ConditionalOnMissingBean (types: org.springframework.cloud.context.properties.ConfigurationPropertiesBeans; SearchStrategy: current) found no beans (OnBeanCondition)
  
     ConfigurationPropertiesRebinderAutoConfiguration#configurationPropertiesRebinder matched
        - @ConditionalOnMissingBean (types: org.springframework.cloud.context.properties.ConfigurationPropertiesRebinder; SearchStrategy: current) found no beans (OnBeanCondition)
  
     EncryptionBootstrapConfiguration matched
        - @ConditionalOnClass classes found: org.springframework.security.crypto.encrypt.TextEncryptor (OnClassCondition)
  
     PropertyPlaceholderAutoConfiguration#propertySourcesPlaceholderConfigurer matched
        - @ConditionalOnMissingBean (types: org.springframework.context.support.PropertySourcesPlaceholderConfigurer; SearchStrategy: current) found no beans (OnBeanCondition)
  
  
  Negative matches:
  -----------------
  
     ConfigServiceBootstrapConfiguration.RetryConfiguration did not match
        - required @ConditionalOnClass classes not found: org.springframework.retry.annotation.Retryable,org.aspectj.lang.annotation.Aspect (OnClassCondition)
  
     DiscoveryClientConfigServiceBootstrapConfiguration did not match
        - @ConditionalOnProperty missing required properties spring.cloud.config.discovery.enabled (OnPropertyCondition)
  
     EncryptionBootstrapConfiguration.RsaEncryptionConfiguration did not match
        - @ConditionalOnClass classes found: org.springframework.security.rsa.crypto.RsaSecretEncryptor (OnClassCondition)
        - Keystore nor key found in Environment (EncryptionBootstrapConfiguration.KeyCondition)
  
     EncryptionBootstrapConfiguration.VanillaEncryptionConfiguration did not match
        - required @ConditionalOnMissing classes found: org.springframework.security.rsa.crypto.RsaSecretEncryptor (OnClassCondition)
  
     EurekaDiscoveryClientConfigServiceBootstrapConfiguration did not match
        - @ConditionalOnClass classes found: org.springframework.cloud.config.client.ConfigServicePropertySourceLocator (OnClassCondition)
        - @ConditionalOnProperty missing required properties spring.cloud.config.discovery.enabled (OnPropertyCondition)
  
  
  Exclusions:
  -----------
  
      None
  
  
  Unconditional classes:
  ----------------------
  
      None
  </code></pre>