[Mapster Tool] Add support for global:: to disambiguate type names in generated mappers #1020

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1. DocSvartz commented on Sep 16, 2026

   

   DocSvartz

   on Sep 16, 2026

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   Hi @BladeWise.
   With which Mapster Tool settings does the generation of using statements occur after the namespace declaration?

   This looks more like some kind of output sequence bug 🤔

   The standard behavior is as follows:

   // generated file
   
   using ThirdParty.Models;
   using Company.Models;
   
   namespace Prefix.Company.Mappers
   {
       
       public partial class Mapper
       {
           MyModel Map(OtherModel model);
       }
   }
   
   // end generated file
   
2. BladeWise commented on Sep 17, 2026

   

   BladeWise

   on Sep 17, 2026

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   My example was probably misleading due to my linter moving usings inside the namespace (which changes the namespace resolution rules), but the problem is with the -p option which generates namespace-qualified type names.

   Attached is a solution with a repro project.
   What happens is that without -p Mapster generates this (as you said)

   using Company.Models;
   using Prefix.Company;
   using ThirdParty.Models;
   
   namespace Prefix.Company
   {
       public partial class MyMapper : IMyMapper
       {
           public MyModel Map(OtherModel p1)
           {
               return p1 == null ? null : new MyModel() {Id = p1.Id};
           }
       }
   }

   which compiles fine, but using -p it generats this

   namespace Prefix.Company
   {
       public partial class MyMapper : Prefix.Company.IMyMapper
       {
           public Company.Models.MyModel Map(ThirdParty.Models.OtherModel p1)
           {
               return p1 == null ? null : new Company.Models.MyModel() {Id = p1.Id};
           }
       }
   }

   which exhibits the problem

   The type or namespace name 'Models' does not exist in the namespace 'Prefix.Company' (are you missing an assembly reference?)
   

   The simpler fix would be to include a global:: prefix to the namespace-qualified type names (which is quite common in generators to avoid namespace resolution issues)

   namespace Prefix.Company
   {
       public partial class MyMapper : global::Prefix.Company.IMyMapper
       {
           public global::Company.Models.MyModel Map(global::ThirdParty.Models.OtherModel p1)
           {
               return p1 == null ? null : new global::Company.Models.MyModel() {Id = p1.Id};
           }
       }
   }

   eventually, enabling this behavior with a dedicated switch.

   Sorry for the misleading sample in my first post!

   👍React with 👍1Reacted by DocSvartz
3. DocSvartz

   added

   improvement

   on Sep 17, 2026
4. DocSvartz commented on Sep 17, 2026

   

   DocSvartz

   on Sep 17, 2026

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   @andrerav @stagep
   I think this can be done as a default behavior when generation using the -p option.
   If this doesn’t cause problems when using aliases. (need tests)

   What are your think about this?
5. DocSvartz

   linked a pull request that will close this issueMapsterTool added global:: prefix when PrintFullTypeName enable #1026on Oct 19, 2026
6. DocSvartz commented on Oct 21, 2026

   

   DocSvartz

   on Oct 21, 2026

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   Hi, @BladeWise In the pre-release version 10.0.14-pre01,
   the -p option generates types using the global:: prefix.
7. BladeWise commented on Oct 21, 2026

   

   BladeWise

   on Oct 21, 2026

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   Thanks a lot for the fix!