Add some unittests for DoubleToString.

Add some unittests for DoubleToString.

Some of these test cases are causing crashes in the wild. They don't
crash on my machine, with or without the dtoa patch, but we may as
well check in the test cases.

BUG=123157
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=137301

[eroman, 2012-05-14 22:52:38]

lgtm

https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
File base/string_number_conversions_unittest.cc (right):

https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
base/string_number_conversions_unittest.cc:350: std::string expected;
I would suggest making this a |const char*| instead. But I see that other
functions in this file use std::string so I guess that is fine.

https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
base/string_number_conversions_unittest.cc:354: {1.33518e+012, "1.33518e+12"},
Note that these are NOT the exact same values as I listed in that bug.

1.33518e+12 = 00 00 b0 df ee 6d 73 42
1.33489e+12 = 00 00 e8 4e da 6c 73 42

Whereas in bug 123157 the first two values were:

00 00 00 00 ee 6d 73 42 (1.33518e+12)
00 00 00 a0 da 6c 73 42 (1.33489e+12)

Notice that bytes 2 and 3 are different.

I suggest running at least a local test using the exact same bytes in the
underlying floating point to see if that is tickling anything.

For the purposes of this CL and adding tests, the way you have it written is
fine though.

[Mark Mentovai, 2012-05-14 23:20:31]

https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
File base/string_number_conversions_unittest.cc (right):

https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
base/string_number_conversions_unittest.cc:350: std::string expected;
eroman wrote:
> I would suggest making this a |const char*| instead. But I see that other
> functions in this file use std::string so I guess that is fine.

This should be const char* to avoid an exit-time destructor.

[tony, 2012-05-14 23:24:59]

On 2012/05/14 22:52:38, eroman wrote:
> lgtm
> 
>
https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
> File base/string_number_conversions_unittest.cc (right):
> 
>
https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
> base/string_number_conversions_unittest.cc:350: std::string expected;
> I would suggest making this a |const char*| instead. But I see that other
> functions in this file use std::string so I guess that is fine.

Switched to const char*.

>
https://chromiumcodereview.appspot.com/10332159/diff/1/base/string_number_con...
> base/string_number_conversions_unittest.cc:354: {1.33518e+012, "1.33518e+12"},
> Note that these are NOT the exact same values as I listed in that bug.
> 
> 1.33518e+12 = 00 00 b0 df ee 6d 73 42
> 1.33489e+12 = 00 00 e8 4e da 6c 73 42
> 
> Whereas in bug 123157 the first two values were:
> 
> 00 00 00 00 ee 6d 73 42 (1.33518e+12)
> 00 00 00 a0 da 6c 73 42 (1.33489e+12)
> 
> Notice that bytes 2 and 3 are different.
> 
> I suggest running at least a local test using the exact same bytes in the
> underlying floating point to see if that is tickling anything.

Ah, you're right!  The printed values are truncated.  I added 2 test cases with
the exact same values.

[Mark Mentovai, 2012-05-15 00:01:02]

LGTM

[commit-bot: I haz the power, 2012-05-15 21:43:19]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tony@chromium.org/10332159/3

[commit-bot: I haz the power, 2012-05-15 23:35:07]

Change committed as 137301