Remove dangerous std::string constructor for der::Input

net/der/input_unittest.cc

Index: net/der/input_unittest.cc
diff --git a/net/der/input_unittest.cc b/net/der/input_unittest.cc
index dc58d4b0d0399094584254b06c1c84713b057f70..a72fae91a1ea6f59b3484c4178b88280241ac119 100644
--- a/net/der/input_unittest.cc
+++ b/net/der/input_unittest.cc
@@ -17,8 +17,8 @@ TEST(InputTest, Equals) {
   Input test2(kInput, arraysize(kInput));
   EXPECT_TRUE(test.Equals(test2));
 
-  std::string input_copy(reinterpret_cast<const char*>(kInput),
-                         arraysize(kInput));
+  uint8_t input_copy[arraysize(kInput)] = {0};
+  memcpy(input_copy, kInput, arraysize(kInput));

[Ryan Sleevi, 2015/05/26 18:53:30]

It's unclear what this is testing or why it's necessary

[nharper, 2015/05/26 22:11:49]

It's testing that 2 Inputs are equal that point to different data, but the
underlying data is the same. The above test (with test and test2) isn't enough
because they both point to the same underlying data kInput.

   Input test_copy(input_copy);
   EXPECT_TRUE(test.Equals(test_copy));
 
@@ -35,6 +35,15 @@ TEST(InputTest, StaticArray) {
   EXPECT_TRUE(input.Equals(input2));
 }
 
+TEST(InputTest, FromCString) {
+  Input from_array(kInput);
+  Input from_string = Input::FromCString("test");
+  EXPECT_TRUE(from_array.Equals(from_string));
+
+  Input zero_length = Input::FromCString("");
+  EXPECT_EQ(0u, zero_length.Length());
+}
+
 TEST(ByteReaderTest, NoReadPastEnd) {
   ByteReader reader(Input(nullptr, 0));
   uint8_t data;
@@ -85,7 +94,7 @@ TEST(ByteReaderTest, ReadToMark) {
 TEST(ByteReaderTest, CantReadToWrongMark) {
   Input out;
   Input in1(kInput, arraysize(kInput));
-  Input in2("test");
+  Input in2 = Input::FromCString("test");
   ByteReader reader1(in1);
   ByteReader reader2(in2);
   ASSERT_TRUE(reader1.ReadBytes(2, &out));