Make string_util::WriteInto() DCHECK() that the supplied |length_with_null| > 1, meaning that the...

base/rand_util_unittest.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/rand_util.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 23 matching lines @@
   char buffer[buffer_size];
   memset(buffer, 0, buffer_size);
   base::RandBytes(buffer, buffer_size);
   std::sort(buffer, buffer + buffer_size);
   // Probability of occurrence of less than 25 unique bytes in 50 random bytes
   // is below 10^-25.
   EXPECT_GT(std::unique(buffer, buffer + buffer_size) - buffer, 25);
 }
 
 TEST(RandUtilTest, RandBytesAsString) {
-  std::string random_string = base::RandBytesAsString(0);
-  EXPECT_EQ(0U, random_string.size());
+  std::string random_string = base::RandBytesAsString(1);
+  EXPECT_EQ(1U, random_string.size());
   random_string = base::RandBytesAsString(145);
   EXPECT_EQ(145U, random_string.size());
   char accumulator = 0;
   for (size_t i = 0; i < random_string.size(); ++i)
     accumulator |= random_string[i];
   // In theory this test can fail, but it won't before the universe dies of
   // heat death.
   EXPECT_NE(0, accumulator);
 }
 
@@ skipping 57 matching lines @@
     uint64 value = base::RandUint64();
     found_ones |= value;
     found_zeros &= value;
 
     if (found_zeros == kAllZeros && found_ones == kAllOnes)
       return;
   }
 
   FAIL() << "Didn't achieve all bit values in maximum number of tries.";
 }