# HG changeset patch
# User Christian Humer <christian.humer@gmail.com>
# Date 1377779312 -7200
# Node ID e55e24cc3e7bf390d105413db0c5bc8c71f69a35
# Parent  5fbd1ba4a5f3514cdb9448dd1033d56b0fac4439
Truffle-DSL: added permutation util functions to the TestHelper.

diff -r 5fbd1ba4a5f3 -r e55e24cc3e7b graal/com.oracle.truffle.api.dsl.test/src/com/oracle/truffle/api/dsl/test/TestHelper.java
--- a/graal/com.oracle.truffle.api.dsl.test/src/com/oracle/truffle/api/dsl/test/TestHelper.java	Wed Aug 28 18:45:32 2013 +0200
+++ b/graal/com.oracle.truffle.api.dsl.test/src/com/oracle/truffle/api/dsl/test/TestHelper.java	Thu Aug 29 14:28:32 2013 +0200
@@ -75,4 +75,44 @@
         return createCallTarget(node).call(new TestArguments(values));
     }
 
+    static Object array(Object... val) {
+        return val;
+    }
+
+    static <E> List<List<E>> permutations(List<E> list) {
+        return permutations(new ArrayList<E>(), list, new ArrayList<List<E>>());
+    }
+
+    static Object[][] permutations(Object... list) {
+        List<List<Object>> permutations = permutations(Arrays.asList(list));
+
+        Object[][] a = new Object[permutations.size()][];
+        int index = 0;
+        for (List<Object> p : permutations) {
+            a[index] = p.toArray(new Object[p.size()]);
+            index++;
+        }
+
+        return a;
+    }
+
+    static <E> List<List<E>> permutations(List<E> prefix, List<E> suffix, List<List<E>> output) {
+        if (suffix.size() == 1) {
+            ArrayList<E> newElement = new ArrayList<>(prefix);
+            newElement.addAll(suffix);
+            output.add(newElement);
+            return output;
+        }
+
+        for (int i = 0; i < suffix.size(); i++) {
+            List<E> newPrefix = new ArrayList<>(prefix);
+            newPrefix.add(suffix.get(i));
+            List<E> newSuffix = new ArrayList<>(suffix);
+            newSuffix.remove(i);
+            permutations(newPrefix, newSuffix, output);
+        }
+
+        return output;
+    }
+
 }