VersionConverter.ConvertTo/From may fail with Version and InstanceDescriptor types

[koszeggy]

Description

When I accidentally used the System.ComponentModel.VersionConverter class in my unit tests instead of my VersionConverter it turned out that the System implementation may fail in some cases.

Reproduction

• Call VersionConverter.ConvertTo with a Version instance that has only two or three version number elements and use destinationType: typeof(Version). The instantiation will fail because Version(int,int,int,int) constructor does not accept -1 values.
• Call VersionConverter.ConvertFrom with an InstanceDescriptor returned by the VersionConverter.ConvertTo method from a similar Version instance.

Suggested fix

• To convert to a Version use Version.Clone instead
• To create an InstanceDescriptor use the string constructor or the Parse method instead.

Other information

I looked at the runtime unit tests and it seems that Version and InstanceDescriptor target types are not tested for actual conversions but only for the CanConvertTo/CanConvertFrom methods.

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Issue Details

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Description

When I accidentally used the System.ComponentModel.VersionConverter class in my unit tests instead of my VersionConverter it turned out that the System implementation may fail in some cases.

Reproduction

• Call VersionConverter.ConvertTo with a Version instance that has only two or three version number elements and use destinationType: typeof(Version). The instantiation will fail because Version(int,int,int,int) constructor does not accept -1 values.
• Call VersionConverter.ConvertFrom with an InstanceDescriptor returned by the VersionConverter.ConvertTo method from a similar Version instance.

Suggested fix

• To convert to a Version use Version.Clone instead
• To create an InstanceDescriptor use the string constructor or the Parse method instead.

Other information

I looked at the runtime unit tests and it seems that Version and InstanceDescriptor target types are not tested for actual conversions but only for the CanConvertTo/CanConvertFrom methods.

Author:	koszeggy
Assignees:	-
Labels:	area-System.ComponentModel, untriaged
Milestone:	-