Merge pull request #65 from udalov/master

File.listFiles(filter)

libraries/stdlib/src/kotlin/io/Files.kt

@@ -202,3 +202,12 @@ fun File.readLines(charset : String = "UTF-8") : List<String> {
 
     return rs
 }
+
+/**
+ * Returns an array of files and directories in the directory that satisfy the specified filter.
+ */
+fun File.listFiles(filter : (file : File) -> Boolean) : Array<File>? = listFiles(
+    object : FileFilter {
+        override fun accept(file: File?) = filter(file!!)
+    }
+) as Array<File>?

libraries/stdlib/test/IoTest.kt

@@ -71,4 +71,19 @@ class IoTest() : TestCase() {
 
     assertEquals(arrayList("Hello", "World"), list)
   }
+  
+  fun testListFiles() {
+    val dir = File.createTempFile("temp", System.nanoTime().toString())!!
+    dir.delete()
+    dir.mkdir()
+    
+    File.createTempFile("temp", "1.kt", dir)
+    File.createTempFile("temp", "2.java", dir)
+    File.createTempFile("temp", "3.kt", dir)
+    
+    val result = dir.listFiles { it.getName()!!.endsWith(".kt") }
+    
+    assertNotNull(result)
+    assertEquals(result!!.size, 2)
+  }
 }