tests: add (failing) tests for random Array "sorting"

These tests fail because we do not implement the exact same algorithm
as Flash Player:
- in AVM1, the test produces a different result
- in AVM2, the test panics because Rust's sort doesn't accomodate
  non-Ord comparison functions

Author: moulins

tests/tests/swfs/avm1/array_sort_random/Test.as

@@ -0,0 +1,38 @@
+// Compile with:
+//  mtasc -main -version 8 Test.as -out test.swf 
+class Test {
+
+  static function main(current) {
+    var array = [];
+    for (var i = 0; i < 50; i++) {
+      array.push(i);
+    }
+
+    // "sort" the array using randomly-chosen comparison results.
+    array.sort(function(a, b) {
+      var r = Test.rng();
+      if (r % 8 == 0) {
+        trace("cmp: " + a + " == " + b);
+        return 0;
+      } else if (r > 0) {
+        trace("cmp: " + a + " > " + b);
+        return 1;
+      } else {
+        trace("cmp: " + a + " < " + b);
+        return -1;
+      }
+    });
+
+    trace("// contents of array");
+    trace(array);
+  }
+
+  // A simple deterministic PRNG; namely, Xorshift.
+  static var rngState = 0x12345678;
+  static function rng() {
+    rngState ^= rngState << 13;
+    rngState ^= rngState >>> 17;
+    rngState ^= rngState << 5;
+    return rngState;
+  }
+}