win: avoid warnings in string_number_conversion_test.cc

util/stdlib/string_number_conversion_test.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 35 matching lines @@
       {"0x10", true, 16},
       {"-0x10", true, -16},
       {"+0x20", true, 32},
       {"0xf", true, 15},
       {"0xg", false, 0},
       {"0x7fffffff", true, std::numeric_limits<int>::max()},
       {"0x7FfFfFfF", true, std::numeric_limits<int>::max()},
       {"0x80000000", false, 0},
       {"0xFFFFFFFF", false, 0},
       {"-0x7fffffff", true, -2147483647},
+#if defined(COMPILER_MSVC)

[Mark Mentovai, 2014/12/16 14:17:47]

build/build_config.h for this if it’s still necessary—see the next comment.

+#pragma warning(push)
+// Unary minus applied to unsigned type, result still unsigned.
+#pragma warning(disable: 4146)
+#endif
       {"-0x80000000", true, -2147483648},

[Mark Mentovai, 2014/12/16 14:17:47]

Would static_cast<>() also silence the warning? I think that’d be preferable.

[scottmg, 2014/12/16 17:53:56]

Cast inside i.e. -static_cast<int>(2147483648) avoids the warning but looks a
little strange.

... It's going to be 0x80000000 regardless of -, perhaps just writing that?

+#if defined(COMPILER_MSVC)
+#pragma warning(pop)
+#endif
       {"-0x80000001", false, 0},
       {"-0xffffffff", false, 0},
       {"0x100000000", false, 0},
       {"0xabcdef", true, 11259375},
       {"010", true, 8},
       {"-010", true, -8},
       {"+020", true, 16},
       {"07", true, 7},
       {"08", false, 0},
       {" 0", false, 0},
@@ skipping 34 matching lines @@
       if (valid) {
         EXPECT_EQ(kTestData[index].value, value)
             << "index " << index << ", string " << kTestData[index].string;
       }
     } else {
       EXPECT_FALSE(valid) << "index " << index << ", string "
                           << kTestData[index].string << ", value " << value;
     }
   }
 
-  // Ensure that embedded NUL characters are treated as bad input.
-  const char input[] = "6\0006";
+  // Ensure that embedded NUL characters are treated as bad input. The string
+  // is split to avoid MSVC warning:
+  //   "decimal digit terminates octal escape sequence".
+  const char input[] = "6\000" "6";
   base::StringPiece input_string(input, arraysize(input) - 1);
   int output;
   EXPECT_FALSE(StringToNumber(input_string, &output));
 
   // Ensure that a NUL is not required at the end of the string.
   EXPECT_TRUE(StringToNumber(base::StringPiece("66", 1), &output));
   EXPECT_EQ(6, output);
 }
 
 TEST(StringNumberConversion, StringToUnsignedInt) {
@@ skipping 74 matching lines @@
       if (valid) {
         EXPECT_EQ(kTestData[index].value, value)
             << "index " << index << ", string " << kTestData[index].string;
       }
     } else {
       EXPECT_FALSE(valid) << "index " << index << ", string "
                           << kTestData[index].string << ", value " << value;
     }
   }
 
   // Ensure that embedded NUL characters are treated as bad input.

[Mark Mentovai, 2014/12/16 14:17:47]

The existing comment was duplicated from above, so your note about splitting the
string should be too.

[scottmg, 2014/12/16 17:53:56]

Done.

-  const char input[] = "6\0006";
+  const char input[] = "6\000" "6";
   base::StringPiece input_string(input, arraysize(input) - 1);
   unsigned int output;
   EXPECT_FALSE(StringToNumber(input_string, &output));
 
   // Ensure that a NUL is not required at the end of the string.
   EXPECT_TRUE(StringToNumber(base::StringPiece("66", 1), &output));
   EXPECT_EQ(6u, output);
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace crashpad