Publish a single file app does not create a single file

[JoeMarkov]

Version Used:
C:\Temp\HelloConsole>dotnet --version
5.0.100-rc.2.20479.15

Steps to Reproduce:

1. Creating a new dotnet console application
2. Publish it as a single file using

dotnet publish -r win-x64 -p:PublishSingleFile=true --self-contained true
or
dotnet publish -r win10-x64 /p:PublishSingleFile=true

3. then I get these files created:

11/04/2020 02:54 PM

.
11/04/2020 02:54 PM ..
09/25/2020 10:47 PM 747,912 clrcompression.dll
09/25/2020 10:46 PM 1,324,416 clrjit.dll
09/25/2020 10:47 PM 5,154,696 coreclr.dll
11/04/2020 02:54 PM 53,289,026 HelloConsole.exe
11/04/2020 02:50 PM 9,352 HelloConsole.pdb
09/25/2020 10:46 PM 1,042,792 mscordaccore.dll

Expected Behavior:

I would expect to only get one file.

Actual Behavior:

I get many files. So bit confused here.... Why I don't get a single file?. I get the same result when I publish from inside visual Studio as well.

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[PathogenDavid]

Roslyn doesn't handle single file publishing, this issue is better suited for https://github.com/dotnet/runtime and would beThis issue is a duplicate of #43071

Currently single file publishing is only single file as far as the managed .NET portions of your app are concerned. As such, some extra files have to be included for native runtime components unless you specify --self-contained false. (Except on Linux where the native components are statically linked to the resulting executable.)

I believe #43556 fixed this, but I'm pretty sure it didn't make the .NET 5 release so you'll have to wait for .NET 6.

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[vitek-karas]

For .NET 5 this is the expected behavior - see the detailed design here: https://github.com/dotnet/designs/blob/main/accepted/2020/single-file/design.md#user-experience

We're working on improving this for future releases - most of the work to get to one file even on Windows is tracked here: #43071

[steveoh]

As such, some extra files have to be included for native runtime components unless you specify --self-contained false.

Isn't this the default?

[vitek-karas]

@steveoh Unfortunately the behavior of dotnet CLI is a bit weird:

• If there's no RuntimeIdentifier specified (so the app is built as portable), then --self-contained is defaulted to false.
• It RuntimeIdentifier is specified (which is a requirement for single-file), then --self-contained is defaulted to true.

[agocke]

As of .NET 6 Preview 1, both Windows and Mac should now compile all the runtime binaries into a single-file, and publishing should produce a true single-file app.

Any native dependencies that the app itself brings in can be bundled and extracted using IncludeNativeBinariesForSelfExtract