Scaffold-DbContext causes "Invalid JSON file in..." if project.json includes comments

[rjpaulsen]

1. If I update my project.json includes a comment, like this:

  // required for EF
  "buildOptions": {
    "emitEntryPoint": true
  },

1. Then I run this:
   Scaffold-DbContext {ConnectionString} Microsoft.EntityFrameworkCore.SqlServer
2. I get the error:

Invalid JSON file in C:\Users...\project.json

1. It works correctly if I change step 1 to look like this:

  "buildOptions": {
    "emitEntryPoint": true
  },

[natemcmaster]

The JSON spec doesn't support comments. Visual Studio tooling hides this from you by stripping comments out of JSON files when it builds.

[bricelam]

Also, we rely on APIs from dotnet/cli to do the JSON parsing. You can read (a lot) more about their decision not to support comments in aspnet/Announcements#24.

Closing as an external issue.

[SDS-Group]

Just in case this helps anyone else - I also had this issue when there was a trailing comma at the end of the projects.json file, which is ignored by the compiler but this tool doesn't like it.

[simeyla]

Can't the error message be changed? "JSON file invalid - cannot contain comments."

It is VERY confusing when VS allows me to comment something in JSON. I kind of intrinsically know that JSON doesn't support comments, but then at the same time I'm not quite sure - and it goes green when I try so it all looks good.

[rowanmiller]

project.json/xproj are being retired in favor of the MSBuild based .NET Core solution. In general, we are helping folks find workarounds for project.json/xproj but focusing our development effort on the project system that is going to reach RTM.