[hack] adding a test file about variadic arguments

Summary:
Now that Textual is able to translate variadic arguments to SIL,
we need to tell Pulse how to analyse them. We set the playground with this test.

Reviewed By: vsiles

Differential Revision:
D50120795

Privacy Context Container: L1208441

fbshipit-source-id: d47704c3e4ee66666afabf44030ae970164ee816

infer/tests/codetoanalyze/hack/pulse/variadic.hack

@@ -0,0 +1,63 @@
+// Copyright (c) Facebook, Inc. and its affiliates.
+//
+// This source code is licensed under the MIT license found in the
+// LICENSE file in the root directory of this source tree.
+
+namespace DictTests;
+
+class Variadic {
+
+  public static function variadicArgInSink(int $i, int ...$args) : void {
+    foreach ($args as $arg) {
+      \Level1\taintSink($arg);
+    }
+  }
+
+  public static function variadicArg0InSink(int $i, int ...$args) : void {
+    \Level1\taintSink($args[0]);
+  }
+
+  public static function callVariadic(int ...$args) : void {
+    self::variadicArgInSink(0, ...$args);
+  }
+
+  public static function FN_callVariadicWith2ArgsBad(int $i) : void {
+    self::variadicArgInSink(0, \Level1\taintSource());
+  }
+
+  public static function callVariadicWith2ArgsOk(int $i) : void {
+    self::variadicArgInSink(\Level1\taintSource(), 0);
+  }
+
+  public static function FN_callVariadicWith3ArgsBad() : void {
+    self::variadicArgInSink(0, 0, \Level1\taintSource());
+  }
+
+  public static function FN_callVariadicWith3ArgsBisBad() : void {
+    self::variadicArgInSink(0, \Level1\taintSource(), 0);
+  }
+
+  public static function FN_transitiveCallVariadicWith2ArgsBad(int $i) : void {
+    self::callVariadic(\Level1\taintSource());
+  }
+
+  public static function FN_transitiveCallVariadicWith3ArgsBad() : void {
+    self::callVariadic(0, \Level1\taintSource());
+  }
+
+  public static function FN_transitiveCallVariadicWith3ArgsBisBad() : void {
+    self::callVariadic(\Level1\taintSource(), 0);
+  }
+
+  public static function FN_callVariadicArg0InSinkBad() : void {
+    self::variadicArg0InSink(0, \Level1\taintSource());
+  }
+
+  public static function callVariadicArg0InSinkOk() : void {
+    self::variadicArg0InSink(0, 0, \Level1\taintSource());
+  }
+
+  public static function callVariadicArg0InSinkBisOk() : void {
+    self::variadicArg0InSink(\Level1\taintSource());
+  }
+}