[GROOVY-7098] looping of java.lang.Iterable or java.lang.Iterator objects in CompileStatic mode

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.3.8
• Component/s: Static compilation
• Assignee: Cédric Champeau
• Reporter: Lari Hotari
• Created: 04/Oct/14 04:13
• Updated: 17/Dec/14 13:25
• Resolved: 08/Oct/14 05:04

Description

There are problems in looping of Iterable or Iterator objects in CompileStatic mode. The behaviour is different from dynamic mode.

better example:

@groovy.transform.CompileStatic
class Iterables {
    Iterable<Object> toIterable(List list) {
        return new Iterable<Object>() {
            Iterator iterator() {
                list.iterator()
            }
        }
    } 
    
    void loopIterable(List list) {
        for(Object o : toIterable(list)) {
            println o
        }
    }
    
    void loopIterator(List list) {
        for(Object o : toIterable(list).iterator()) {
            println o
        }
    }
    
    public static void main(String[] args) {
        new Iterables().loopIterable([1, 2, 3])
        new Iterables().loopIterator([4, 5, 6])
    }
}

prints

Iterables$1@6f4d33
java.util.ArrayList$Itr@90ff2a1

prints in dynamic mode

1
2
3
4
5
6

—

EDITED: original example:

I was able to reproduce the problem with this code example (runnable in GroovyConsole):

@Grab("org.yaml:snakeyaml:1.14")
import org.yaml.snakeyaml.Yaml

@groovy.transform.CompileStatic
class YmlLoader {
    Map map

    @groovy.transform.CompileDynamic
    public void loadYmlDynamic(InputStream input) {
        Yaml yaml = new Yaml()
        for(Object yamlObject : yaml.loadAll(input)) {
            if(yamlObject instanceof Map) {
                map = (Map)yamlObject
            }
        }
    }

    public void loadYmlStatic(InputStream input) {
        Yaml yaml = new Yaml()
        for(Object yamlObject : yaml.loadAll(input)) {
            if(yamlObject instanceof Map) { // problem here with CompileStatic
                map = (Map)yamlObject
            }
        }
    }
}

YmlLoader a = new YmlLoader()
a.loadYmlDynamic new ByteArrayInputStream("a: 1".getBytes())
a.map

YmlLoader b = new YmlLoader()
b.loadYmlDynamic new ByteArrayInputStream("a: 1".getBytes())
assert a.map == b.map

YmlLoader c = new YmlLoader()
c.loadYmlStatic new ByteArrayInputStream("a: 1".getBytes())
assert a.map == c.map