foreach expected but while used instead

[greenozon]

ILSpy version 5.0.0.4970-preview3

method decompiled with while but foreach expected

protected CompositeDevices(SerializationInfo info, StreamingContext context)
	: base(info, context)
{
	SerializationInfoEnumerator enumerator = info.GetEnumerator();
	while (enumerator.MoveNext())
	{
		string name = enumerator.Current.Name;
		if (name != null && name == "AdditionalParameters")
		{
			AdditionalParameters = (Dictionary<string, string>)info.GetValue("AdditionalParameters", typeof(Dictionary<string, string>));
		}
	}
	base.CollectionChanged += OnCollectionChanged;
}

please also ref to very similar method
CompositeDevices(IEnumerable col)
that decompiled to foreach!

target: #1601

PS this assemlby has a lot of other locations that are decompiled to while loop instead of much more expected foreach!

[dgrunwald]

SerializationInfoEnumerator implements IEnumerator but not IDisposable, so the compiler doesn't generate a using statement / try-finally block.
I think currently our foreach pattern only tries to match using statements.

[greenozon]

Did a little investigation - how competitors are handling this case
so,
.NET Reflector as well as Telerik are using

while (enumerator.MoveNext())

but JetBrains and dnSpy are using

foreach (SerializationEntry serializationEntry in info)

so, to summarize

1. it's possilbe
2. it's "nice to have & see" feature, not an error

Feel free to close this issue.

[siegfriedpammer]

See the relevant test case at

ILSpy/ICSharpCode.Decompiler.Tests/TestCases/Pretty/Loops.cs

Lines 358 to 366 in ddf4053

	// TODO : Needs additional pattern detection
	// CustomStructEnumerator does not implement IDisposable
	// No try-finally-Dispose is generated.
	//public void ForEachOnGenericCustomStructEnumerator<T>(CustomStructEnumerator<T> e)
	//{
	// foreach (T item in e) {
	// Console.WriteLine(item);
	// }
	//}