PropertySourcesConfig implements Cloneable

[PaulWaldo]

I am in the process of attempting to port the Grails Platform Core plugin to a 3.x plugin. When it merges the configuration of all of the plugins it controls with the main application configuration, it wants to clone the main configuration. The comment in the code states the reason for the clone:

Deep clone app config to avoid side effects of querying existing config values

The current grails-core (without this change) throws the following exception when run-apping platform-core:

java.lang.CloneNotSupportedException: org.grails.config.PropertySourcesConfig
    at java.lang.Object.clone(Native Method) ~[na:1.8.0_60]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_60]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_60]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_60]
    at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_60]
    at org.springsource.loaded.ri.ReflectiveInterceptor.jlrMethodInvoke(ReflectiveInterceptor.java:1426) ~[springloaded-1.2.5.RELEASE.jar:1.2.5.RELEASE]
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite$PojoCachedMethodSiteNoUnwrapNoCoerce.invoke(PojoMetaMethodSite.java:233) ~[groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:56) ~[groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48) [groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113) [groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:117) [groovy-2.4.5.jar:2.4.5]
    at org.grails.plugin.platform.config.PluginConfigurationImpl$_mergeDoWithConfig_closure5.doCall(PluginConfigurationImpl.groovy:261) ~[main/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_60]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_60]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_60]
    at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_60]
    at org.springsource.loaded.ri.ReflectiveInterceptor.jlrMethodInvoke(ReflectiveInterceptor.java:1426) ~[springloaded-1.2.5.RELEASE.jar:1.2.5.RELEASE]
    at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:93) ~[groo5.jar:2.4.5]
    at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:325) ~[groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:294) ~[groovy-2.4.5.jar:2.4.5]
Exception in thread "main"  at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1019) ~[groovy-2.4.5.jar:2.4.5]
    at groovy.lang.Closure.call(Closure.java:426) ~[groovy-2.4.5.jar:2.4.5]
java.lang.reflect.UndeclaredThrowableException  at org.grails.plugin.platform.config.PluginConfigurationImpl$_mergeDoWithConfig_closure5.call(PluginConfigurationImpl.groovy) ~[main/:na]

    at groovy.lang.Closure.call(Closure.java:442) ~[groovy-2.4.5.jar:2.4.5]
    at org.springframework.util.ReflectionUtils.rethrowRuntimeException(ReflectionUtils.java:303)
    at org.grails.plugin.platform.config.PluginConfigurationImpl$_mergeDoWithConfig_closure5.call(PluginConfigurationImpl.groovy) ~[main/:na]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:346)
    at org.codehaus.groovy.runtime.DefaultGroovyMethods.each(DefaultGroovyMethods.java:2030) ~[groovy-2.4.5.jar:2.4.5]
    at grails.boot.GrailsApp.run(GrailsApp.groovy:54)
    at org.codehaus.groovy.runtime.DefaultGroovyMethods.each(DefaultGroovyMethods.java:1890) ~[groovy-2.4.5.jar:2.4.5]
    at grails.boot.GrailsApp.run(GrailsApp.groovy:346)
    at org.codehaus.groovy.runtime.dgm$159.invoke(Unknown Source) ~[groovy-2.4.5.jar:2.4.5]
    at grails.boot.GrailsApp.run(GrailsApp.groovy:335)
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite$PojoMetaMethodSiteNoUnwrapNoCoerce.invoke(PojoMetaMethodSite.java:274) ~[groovy-2.4.5.jar:2.4.5]
    at grails.boot.GrailsApp$run.call(Unknown Source)
    at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:56) ~[groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48)
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48) [groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113) [groovy-2.4.5.jar:2.4.5]
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:133)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:125) [groovy-2.4.5.jar:2.4.5]
    at grails.platform.core3.Application.main(Application.groovy:8)
    at org.grails.plugin.platform.config.PluginConfigurationImpl.mergeDoWithConfig(PluginConfigurationImpl.groovy:250) ~[main/:na]
Caused by: java.lang.CloneNotSupportedException: org.grails.config.PropertySourcesConfig
    at org.grails.plugin.platform.config.PluginConfigurationImpl.applyConfig(PluginConfigurationImpl.groovy:174) ~[main/:na]
    at java.lang.Object.clone(Native Method)
    at org.grails.plugin.platform.config.PluginConfigurationImpl$applyConfig.call(Unknown Source) ~[na:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48) [groovy-2.4.5.jar:2.4.5]

[graemerocher]

cloning the config is expensive and impacts startup time, unless there is a really valid reason to do this we won't be adding support for this