Fix parsing of exponents in StringToDouble.

base/strings/string_number_conversions_unittest.cc

 // Copyright (c) 2012 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/strings/string_number_conversions.h"
 
 #include <errno.h>
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
@@ skipping 710 matching lines @@
   } cases[] = {
     {"0", 0.0, true},
     {"42", 42.0, true},
     {"-42", -42.0, true},
     {"123.45", 123.45, true},
     {"-123.45", -123.45, true},
     {"+123.45", 123.45, true},
     {"2.99792458e8", 299792458.0, true},
     {"149597870.691E+3", 149597870691.0, true},
     {"6.", 6.0, true},
+    {"9e307", 9e307, true},
+    {"1.7976e308", 1.7976e308, true},

[danakj, 2016/09/01 23:49:23]

Can you drop a comment on all these new ones where these numbers come from/what
they are testing?

[Lei Zhang, 2016/09/02 01:07:10]

- Added comments for all the groups of cases.
- Added a few more test cases.

+    {"1.7977e308", HUGE_VAL, false},
+    {"9e308", HUGE_VAL, false},
+    {"9e309", HUGE_VAL, false},
+    {"9e999", HUGE_VAL, false},
+    {"9e1999", HUGE_VAL, false},
+    {"9e19999", HUGE_VAL, false},
     {"9e99999999999999999999", HUGE_VAL, false},
+    {"-9e307", -9e307, true},
+    {"-1.7976e308", -1.7976e308, true},
+    {"-1.7977e308", -HUGE_VAL, false},
+    {"-9e308", -HUGE_VAL, false},
+    {"-9e309", -HUGE_VAL, false},
+    {"-9e999", -HUGE_VAL, false},
+    {"-9e1999", -HUGE_VAL, false},
+    {"-9e19999", -HUGE_VAL, false},
     {"-9e99999999999999999999", -HUGE_VAL, false},
     {"1e-2", 0.01, true},
     {"42 ", 42.0, false},
     {" 1e-2", 0.01, false},
     {"1e-2 ", 0.01, false},
     {"-1E-7", -0.0000001, true},
     {"01e02", 100, true},
     {"2.3e15", 2.3e15, true},
     {"\t\n\v\f\r -123.45e2", -12345.0, false},
     {"+123 e4", 123.0, false},
@@ skipping 108 matching lines @@
   };
 
   for (const auto& test : cases) {
     double output;
     EXPECT_TRUE(StringToDouble(test.input, &output));
     EXPECT_EQ(bit_cast<uint64_t>(output), test.expected);
   }
 }
 
 }  // namespace base