Bug 1149174 - Add a test to ensure that XPCOM nsTArray range iterators are stable; r=froydnj

xpcom/tests/TestTArray.cpp

@@ -1157,6 +1157,46 @@ static bool test_SetLengthAndRetainStorage_no_ctor() {
   return true;
 }
 
+bool test_range_based_for_loop_stable_iterator()
+{
+  const int N = 10;
+  FallibleTArray<int> f;
+  AutoFallibleTArray<int, N> fauto;
+
+  InfallibleTArray<int> i;
+  AutoInfallibleTArray<int, N> iauto;
+
+  nsTArray<int> t;
+  nsAutoTArray<int, N> tauto;
+
+#define DO_TEST(var) {             \
+    var.AppendElement(2);          \
+    var.AppendElement(3);          \
+    var.AppendElement(4);          \
+    int count = 0;                 \
+    for (const auto& elem : var) { \
+      if (elem == 2) {             \
+        var.RemoveElementAt(1);    \
+      }                            \
+      ++count;                     \
+    }                              \
+    if (count != 3) {              \
+      return false;                \
+    }                              \
+  }
+
+  DO_TEST(f)
+  DO_TEST(fauto)
+  DO_TEST(i)
+  DO_TEST(iauto)
+  DO_TEST(t)
+  DO_TEST(tauto)
+
+#undef DO_TEST
+
+  return true;
+}
+
 //----
 
 typedef bool (*TestFunc)();
@@ -1185,6 +1225,7 @@ static const struct Test {
   DECL_TEST(test_fallible),
   DECL_TEST(test_conversion_operator),
   DECL_TEST(test_SetLengthAndRetainStorage_no_ctor),
+  DECL_TEST(test_range_based_for_loop_stable_iterator),
   { nullptr, nullptr }
 };