[jira] [Commented] (GROOVY-8096) setScriptBaseClass with Java base class breaks @Field initialization from Binding due to wrong constructor

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/GROOVY-8096?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15877915#comment-15877915 ] 

ASF GitHub Bot commented on GROOVY-8096:
----------------------------------------

Github user kreiger commented on a diff in the pull request:

    https://github.com/apache/groovy/pull/502#discussion_r102426057
  
    --- Diff: src/test/groovy/lang/BindingScript.java ---
    @@ -0,0 +1,32 @@
    +/*
    + *  Licensed to the Apache Software Foundation (ASF) under one
    + *  or more contributor license agreements.  See the NOTICE file
    + *  distributed with this work for additional information
    + *  regarding copyright ownership.  The ASF licenses this file
    + *  to you under the Apache License, Version 2.0 (the
    + *  "License"); you may not use this file except in compliance
    + *  with the License.  You may obtain a copy of the License at
    + *
    + *    http://www.apache.org/licenses/LICENSE-2.0
    + *
    + *  Unless required by applicable law or agreed to in writing,
    + *  software distributed under the License is distributed on an
    + *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    + *  KIND, either express or implied.  See the License for the
    + *  specific language governing permissions and limitations
    + *  under the License.
    + */
    +package groovy.lang;
    +
    +/**
    + * A Script which requires a Binding passed in the constructor and disallows calling the default constructor.
    + */
    +public abstract class BindingScript extends Script {
    +    protected BindingScript() {
    --- End diff --
    
    If i remove both constructors the `super()` call just goes to the default constructor in groovy.lang.Script, giving `MissingPropertyException` on trying to access the wrong `Binding context` on field initalization:
    
        groovy.lang.MissingPropertyException: No such property: args for class: TestBindingsInFieldInitializersWithConfigJavaBaseScript
     	    at TestBindingsInFieldInitializersWithConfigJavaBaseScript.<init>(TestBindingsInFieldInitializersWithConfigJavaBaseScript.groovy:2)
    	    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    	    at groovy.lang.GroovyShell.runScriptOrMainOrTestOrRunnable(GroovyShell.java:271)



> setScriptBaseClass with Java base class breaks @Field initialization from Binding due to wrong constructor
> ----------------------------------------------------------------------------------------------------------
>
>                 Key: GROOVY-8096
>                 URL: https://issues.apache.org/jira/browse/GROOVY-8096
>             Project: Groovy
>          Issue Type: Bug
>          Components: Compiler, GroovyScriptEngine
>    Affects Versions: 2.4.8
>            Reporter: Christoffer Hammarström
>              Labels: test
>
> I created a pull request on GitHub with a failing test showing the problem: https://github.com/apache/groovy/pull/502
> This test fails because {{ModuleNode.setScriptBaseClassFromConfig(ClassNode)}}
> calls {{.setSuperClass(ClassHelper.make(baseClassName))}} on the {{scriptDummy ClassNode}}.
> The {{ClassNode}} created for this script's base class has {{.lazyInitDone = true}} and {{.constructors = null}}
> {{ModuleNode.createStatementsClass()}} calls {{.getSuperClass().getDeclaredConstructor(SCRIPT_CONTEXT_CTOR)}} 
> Then {{ClassNode.constructors}} is set to an empty ArrayList in {{ClassNode.getDeclaredConstructors()}}, insteaf of looking them up from the Java class.
> The script constructor is then generated in {{ModuleNode.createStatementsClass()}} as:
> {code:java}
>      Constructor(Binding context) {
>          super();             // Fields are initialized after the call to super()
>                               // Fields are initialized here with new Binding() instead of context
>          setBinding(context); // Fields are initialized before setBinding
>      }
> {code}
> instead of
> {code:java}
>      Constructor(Binding context) {
>          super(context); // Fields are initialized after the call to super(context)
>      }
> {code}
> We're calling the default constructor in the base class with {{super()}}, instead of passing along the {{Binding context}} with {{super(context)}} 
> This breaks initialization of Fields that depend on the {{Binding context}}, because Fields are initialized between the call to {{super()}} and the {{setBinding(context)}}: http://stackoverflow.com/a/14806340/233014
> This leads to {{MissingPropertyException}} because we're trying to look up variables from the {{new Binding()}} created in the default constructor, instead of the binding we passed in.
> For convenience, here is the failing test:
> {code:title=GroovyShellTest2.groovy}
>     void testBindingsInFieldInitializersWithConfigJavaBaseScript() {
>         def config = new org.codehaus.groovy.control.CompilerConfiguration()
>         config.scriptBaseClass = BindingScript.class.name
>         def shell = new GroovyShell(config);
>         def scriptText = '''
>         @groovy.transform.Field def script_args = getProperty('args')    // Will get MissingPropertyException here 
>                                                                          // if we don't throw UnsupportedOperationException in the default constructor
>         assert script_args[0] == 'Hello Groovy'
>         script_args[0]
> '''
>         def arg0 = 'Hello Groovy'
>         def result = shell.run scriptText, 'TestBindingsInFieldInitializersWithConfigJavaBaseScript.groovy', [arg0]
>         assert result == arg0
>     }
> {code}
> and the Java script base class:
> {code:title=BindingScript.java}
> package groovy.lang;
> /**
>  * A Script which requires a Binding passed in the constructor and disallows calling the default constructor.
>  */
> public abstract class BindingScript extends Script {
>     // Making the default constructor private instead gives IllegalAccessError
>     // Removing the default constructor instead gives NoSuchMethodError
>     // Removing both constructors just calls to the default constructor in groovy.lang.Script giving MissingPropertyException on field initialization
>     protected BindingScript() {
>         throw new UnsupportedOperationException("\n\t*******\n\tBindingScript() should not be called! Should be calling BindingScript(Binding)!\n\t*******");
>     }
>     protected BindingScript(Binding binding) {
>         super(binding);
>     }
> }
> {code}



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