Fix functions List<T>.sort() and add sort functions for java.lang.Iterables.

See Problem 3 at https://github.com/JetBrains/kotlin/pull/78#issuecomment-6533534

libraries/stdlib/src/kotlin/JLangIterablesSpecial.kt

@@ -105,6 +105,18 @@ public fun <T> java.lang.Iterable<T>.withIndices() : java.lang.Iterable<#(Int, T
     }
 }
 
+public inline fun <in T: java.lang.Comparable<T>> java.lang.Iterable<T>.sort() : List<T> {
+    val list = toList()
+    java.util.Collections.sort(list)
+    return list
+}
+
+public inline fun <in T> java.lang.Iterable<T>.sort(comparator: java.util.Comparator<T>) : List<T> {
+    val list = toList()
+    java.util.Collections.sort(list, comparator)
+    return list
+}
+
 private class NumberedIterator<TT>(private val sourceIterator : java.util.Iterator<TT>) : java.util.Iterator<#(Int, TT)> {
     private var nextIndex = 0
 

libraries/stdlib/src/kotlin/JUtil.kt

@@ -40,17 +40,6 @@ public inline fun <in T: java.lang.Comparable<T>> java.lang.Iterable<T>.toSorted
 
 // List APIs
 
-
-public inline fun <in T: java.lang.Comparable<T>> List<T>.sort() : List<T> {
-  Collections.sort(this)
-  return this
-}
-
-public inline fun <in T> List<T>.sort(comparator: java.util.Comparator<T>) : List<T> {
-  Collections.sort(this, comparator)
-  return this
-}
-
 /** Returns the List if its not null otherwise returns the empty list */
 public inline fun <T> java.util.List<T>?.orEmpty() : java.util.List<T>
     = if (this != null) this else Collections.emptyList<T>() as java.util.List<T>

libraries/stdlib/test/CollectionTest.kt

@@ -337,15 +337,21 @@ class CollectionTest {
         expect(arrayList(2, 3, 1)) { iterable }
     }
 
-    test fun sort() {
-        val coll: List<String> = arrayList("foo", "bar", "abc")
-
-        // TODO fixme
-        // Some sort of in/out variance thing - or an issue with Java interop?
-        //coll.sort()
+    test fun sortFunctionShouldReturnSortedCopyForList() {
+        // TODO fixme Some sort of in/out variance thing - or an issue with Java interop?
         todo {
-            assertEquals(3, coll.size)
-            assertEquals(arrayList("abc", "bar", "foo"), coll)
+//            val list : List<Int> = arrayList<Int>(2, 3, 1)
+//            expect(arrayList(1, 2, 3)) { list.sort() }
+//            expect(arrayList(2, 3, 1)) { list }
+        }
+    }
+
+    test fun sortFunctionShouldReturnSortedCopyForIterable() {
+        // TODO fixme Some sort of in/out variance thing - or an issue with Java interop?
+        todo {
+//        val list : java.lang.Iterable<Int> = arrayList(2, 3, 1)
+//        expect(arrayList(1, 2, 3)) { list.sort() }
+//        expect(arrayList(2, 3, 1)) { list }
         }
     }