Fix Random.GetItems breaking change in produced sequence #108017
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Developers, often in tests, rely on seeded Random instances producing the same sequence of values on every use. We made a change in .NET 9, though, that changed the sequence GetItems produces, due to employing a different algorithm. This fixes that special-case to only be used when the developer couldn't rely on the results being deterministic, namely when using either `new Random()` or `Random.Shared`. If a seed is provided or if a custom derived implementation is used, it falls back to the old behavior.
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Started backporting to release/9.0-rc2: https://github.com/dotnet/runtime/actions/runs/10940955057 |
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…otnet#108017) Developers, often in tests, rely on seeded Random instances producing the same sequence of values on every use. We made a change in .NET 9, though, that changed the sequence GetItems produces, due to employing a different algorithm. This fixes that special-case to only be used when the developer couldn't rely on the results being deterministic, namely when using either `new Random()` or `Random.Shared`. If a seed is provided or if a custom derived implementation is used, it falls back to the old behavior.
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Developers, often in tests, rely on seeded Random instances producing the same sequence of values on every use. We made a change in .NET 9, though, that changed the sequence GetItems produces, due to employing a different algorithm. This fixes that special-case to only be used when the developer couldn't rely on the results being deterministic, namely when using either
new Random()orRandom.Shared. If a seed is provided or if a custom derived implementation is used, it falls back to the old behavior.cc: @bartonjs, @vcsjones