5.3.0 breaks global.json with latestFeature

[otemnov]

Description:
action for the following global.json is broken, seems because of this change

{
  "sdk": {
    "version": "8.0",
    "rollForward": "latestFeature"
  }
}

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Repro steps:
Use global.json without feature version specified

{
  "sdk": {
    "version": "8.0",
    "rollForward": "latestFeature"
  }
}

Expected behavior:
Should setup dotnet with no issues

Actual behavior:
Error: Cannot read properties of undefined (reading 'substring')

[priyagupta108]

Hello @otemnov,
Thank you for reporting this issue. We will investigate it and get back to you as soon as we have some feedback.

[Frulfump]

8.0 isn't a valid version according to the docs for global.json https://learn.microsoft.com/en-us/dotnet/core/tools/global-json#version

version

Type: string

The version of the .NET SDK to use.

This field:

Requires the full version number, such as 10.0.100.
Doesn't support version numbers like 10, 10.0, or 10.0.x.
Doesn't have wildcard support.
Doesn't support version ranges.

[nikita-bestuzhev-ct]

@Frulfump, it sounds reasonable, thanks.
But in this case some validation should be introduced in getVersionFromGlobalJson function. To have something like "Version number '8.0' is not valid. The feature part is missing" instead of "Cannot read properties of undefined (reading 'substring')".

[Frulfump]

@Frulfump, it sounds reasonable, thanks.
But in this case some validation should be introduced in getVersionFromGlobalJson function. To have something like "Version number '8.0' is not valid. The feature part is missing" instead of "Cannot read properties of undefined (reading 'substring')".

Yupp I agree 100%

[priyagupta108]

Hi @otemnov, thanks for reporting this.

The sdk.version value in global.json must be a full SDK version, such as 8.0.100. Values like 8, 8.0, or 8.0.x are not supported. So the provided repro with "version": "8.0" is not a valid global.json configuration.

For more details, please see the official documentation: https://learn.microsoft.com/en-us/dotnet/core/tools/global-json#version

In v5.3.0, the action expanded its use of global.json to support rollForward policies, which requires parsing version components such as major, minor, and feature band as defined in Microsoft’s spec.

We will improve the action’s handling so invalid global.json SDK version cases like this fail with a clearer error message. We’ll track this as an error-handling improvement rather than a regression in supported global.json behavior.

To unblock yourself, update your global.json to use a complete SDK version: "version": "8.0.100"

Hope this helps!

[otemnov]

@priyagupta108 thanks for quick reaction! this isn't a blocker for us, we've already pinned to a full SDK version on our side. The reason I filed the issue is that "version": "8.0" had been working fine until v5.3.0, so the silent break was a bit surprising. On our side, it was a useful nudge to fix an broken global.json.