Windows exit codes should be displayed as hex codes and decoded

[peter-ahe-google]

Windows exit codes are a 32-bit unsigned integer and frequently the MSB is set (I believe this happens when there is a crash). This means that reporting it as a signed value is confusing. See issue #15139.

Instead the signed value should follow the Windows convention of printing a 8 digit hex code, possibly prefixed by 0x to avoid confusion between Unix and Windows.

In addition, the test runner should attempt to decode the exit code using err.exe (http://www.microsoft.com/en-us/download/details.aspx?id=985). We should be able to ensure that err.exe is available on the build bots.

If err.exe isn't available, the test runner should suggest downloading it.

[ricowind]

Is that a valid tool to run against other pieces of software than Exchange Server?

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[ricowind]

+sgjesse, +ajohnsen
The exit code reported by IO on windows should probably be treated like a unsigned int

[ricowind]

actually +sgjesse, +ajohnsen

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cc @sgjesse.
cc @Skabet.

[sgjesse]

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[peter-ahe-google]

I don't see how this is a dart:io issue. This is a bug about how a number is printed by our test infrastructure.

As far as I know, weather or not a number is printed in hexadecimal notation is a property of the test infrastructure, not dart:io.

It is possible that there is a related bug in dart:io.

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