[GROOVY-2680] property read accessor defined via metaClass does not work without parameter list terminator in closure

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.5.4
• Fix Version/s: 1.7.9
• Environment: Mac OSX 10.4 Darwin 8.11.1, Groovy 1.5.4, Java 1.5.0_07
• Assignee: Guillaume Sauthier
• Reporter: Scott Sayles
• Created: 11/Mar/08 16:58
• Updated: 12/Mar/11 00:46
• Resolved: 17/Feb/11 06:44

Description

The following is listed in the usage guide as an example of adding a property to an existing class:

class Book {
    String title
}

def properties = Collections.synchronizedMap([:])

Book.metaClass.setAuthor = { String value ->
   properties[System.identityHashCode(delegate) + "author"] = value
}
Book.metaClass.getAuthor = {->
   properties[System.identityHashCode(delegate) + "author"]
}

In other contexts, the -> is generally considered optional. However, if you do not use the -> list terminator in the get method closure, the read accessor does not work. For example, if you instead define getAuthor like:

Book.metaClass.getAuthor = {
   properties[System.identityHashCode(delegate) + "author"]
}

the following occurs when you call the property accessor:

book = new Book()
book.author = "foo" // works
println book.author // does not work

Caught: groovy.lang.MissingPropertyException: No such property: author for class: Book
        at Book.getProperty(propertyTest.groovy)
        at foo.run(propertyTest.groovy:15)
        at foo.main(propertyTest.groovy)

I'm new to Groovy and may very well be missing something, but this does not seem like expected behavior.