[csharp] Mustache fully qualify namespace for Path

[alfredo-accuris]

The generated code of Csharp get a fully quallify namespace for PATH

using Path = global::System.IO.Path;

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[alfredo-accuris]

Intends to fix #19344

[devhl-labs]

Using an alias might lead to more conflicts with other apis that have objects called Path. Please just fully qualify the Path method without using an alias.

[alfredo-accuris]

Update the PR. Fully qualify Path class

[wing328]

using RestSharpMethod = RestSharp.Method;
using FileIO = System.IO.File;

given that we're already using aliases above, shall we follow the same pattern for Path to make it consistent? e.g.

using PathIO = System.IO.Path;

[devhl-labs]

I do not think we should be using aliases. That will make it easier for unexpected conflicts to occur. Using the fully qualified name is more verbose, but also more concise. We don't care about verbosity here because it is generated code anyway.

[wing328]

We don't care about verbosity here because it is generated code anyway.

some users do care about it based on feedback we'd previously when using fully qualified namespace

i don't think giving this one a try

[wing328]

thanks for the PR

with name mapping option for fallback, can this PR target upcoming minor release (breaking with fallback allowed)?

ref: https://github.com/openapitools/openapi-generator/blob/master/docs/customization.md#name-mapping

[devhl-labs]

This is not a breaking change. It is only fully qualifying a method, a very safe thing to do. I don't see any harm in merging it now.