Add explicit flushing to ProcessStartInfoTests

[akoeplinger]

We're seeing some tests fail due to an invalid base64 string, see #76140
We can't repro locally but one cause might be because the string isn't fully written yet, so try flushing.

Also capture the output so we can see what it was when something goes wrong.

[ghost]

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Issue Details

---

We're seeing some tests fail due to an invalid base64 string, see #76140
We can't repro locally but one cause might be because the string isn't fully written yet, so try flushing.

Also capture the output so we can see what it was when something goes wrong.

Author:	akoeplinger
Assignees:	-
Labels:	area-System.Diagnostics.Process
Milestone:	-

[akoeplinger]

/azp run runtime-bionic

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No pipelines are associated with this pull request.

[akoeplinger]

/azp run runtime-linuxbionic

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Azure Pipelines successfully started running 1 pipeline(s).

[filipnavara]

Looks like invalid base64 indeed...

                 =================================================================
                 	Native Crash Reporting
                 =================================================================
                 Got a SIGABRT while executing native code. This usually indicates
                 a fatal error in the mono runtime or one of the native libraries 
                 used by your application.
                 =================================================================
                 
                 No native Android stacktrace (see debuggerd output).
                 
                 =================================================================
                 	Basic Fault Address Reporting
                 =================================================================
                 Memory around native instruction pointer (0x79f2626acc):0x79f2626abc  e3 83 00 91 c2 00 80 52 08 1e 80 52 01 00 00 d4  .......R...R....
                 0x79f2626acc  e1 03 00 91 c0 00 80 52 e2 03 1f aa e0 07 00 ad  .......R........
                 0x79f2626adc  fd ab 01 94 a1 63 00 91 40 00 80 52 e2 03 1f aa  .....c..@..R....
                 0x79f2626aec  f5 ab 01 94 80 15 80 52 17 ab 01 94 f3 03 00 aa  .......R........
                 
                 =================================================================
                 	Managed Stacktrace:
                 =================================================================
                 	  at <unknown> <0xffffffff>
                 	  at Globalization:LoadICU <0x00007>
                 	  at System.Globalization.GlobalizationMode:LoadICU <0x00023>
                 	  at Settings:.cctor <0x000bb>
                 	  at System.Object:runtime_invoke_void <0x0007f>
                 	  at <unknown> <0xffffffff>
                 	  at <unknown> <0xffffffff>
                 	  at System.Globalization.GlobalizationMode:get_Invariant <0x00023>
                 	  at System.Globalization.CultureData:CreateCultureWithInvariantData <0x00df3>
                 	  at System.Globalization.CultureData:get_Invariant <0x0004b>
                 	  at System.Globalization.CultureInfo:.cctor <0x00023>
                 	  at System.Object:runtime_invoke_void <0x0007f>
                 	  at <unknown> <0xffffffff>
                 	  at <unknown> <0xffffffff>
                 	  at System.Globalization.CompareInfo:.cctor <0x00023>
                 	  at System.Object:runtime_invoke_void <0x0007f>
                 	  at <unknown> <0xffffffff>
                 	  at <unknown> <0xffffffff>
                 	  at System.Reflection.AssemblyNameParser:Parse <0x002a7>
                 	  at System.Reflection.AssemblyNameParser:Parse <0x000eb>
                 	  at System.Reflection.AssemblyName:.ctor <0x0008f>
                 	  at Microsoft.DotNet.RemoteExecutor.Program:Main <0x0021b>
                 	  at <Module>:runtime_invoke_int_object <0x00087>
                 =================================================================

[stephentoub]

so try flushing

Isn't the console stream's Flush a nop?

[filipnavara]

so try flushing

Isn't the console stream's Flush a nop?

It is, at least in normal circumstances. The debug print showed the crash message though.

[akoeplinger]

Yeah the flushing was just a shot in the dark, the crash report is indeed why it's not valid base64 😆
Not really sure why it's trying to load ICU at that point though, will need to investigate.

[danmoseley]

It would be good to leave that logging in even after this is fixed.

[stephentoub]

@akoeplinger, if the flushing isn't the issue, should this be closed then?

[ghost]

Draft Pull Request was automatically closed for 30 days of inactivity. Please let us know if you'd like to reopen it.