base::Optional operator bool doesn't convert to bool.

base/optional_unittest.cc

Index: base/optional_unittest.cc
diff --git a/base/optional_unittest.cc b/base/optional_unittest.cc
index 565b6cd6c74cad6679c02c68953176b0dce11c6f..f79490bd8cb5c8da6fe76a6f422712a524c91a89 100644
--- a/base/optional_unittest.cc
+++ b/base/optional_unittest.cc
@@ -441,6 +441,29 @@ TEST(OptionalTest, OperatorArrow) {
   EXPECT_EQ(a->foo(), 3);
 }
 
+TEST(OptionalTest, OperatorBool) {
+  {
+    Optional<TestObject> a;
+    EXPECT_EQ(static_cast<bool>(a), false);  // works.
+  }
+
+  {
+    Optional<TestObject> a;
+    bool b = !!a;  // works.
+    EXPECT_EQ(b, false);
+  }
+
+  {
+    Optional<TestObject> a;
+    bool b = a;
+    // error: no viable conversion from
+    // 'Optional<base::(anonymous namespace)::TestObject>' to 'bool'
+    EXPECT_EQ(b, false);
+  }
+
+  // More to add here... testing true etc.
+}
+
 TEST(OptionalTest, Value_rvalue) {
   EXPECT_EQ(0.1f, Optional<float>(0.1f).value());
   EXPECT_EQ(std::string("foo"), Optional<std::string>("foo").value());