Using StyleCop in Asp.net Core

Question

According to this this article for using StyleCop in Asp.net Core,

1)Add the following to the dependencies section of the project.json file:

 "StyleCop.Analyzers": {
  "version": "1.0.0",
  "type": "build"
}

and build the project.

2) Create stylecop.json and add your configuration on it, this is my stylecop.json content:

{
   "$schema": "https://raw.githubusercontent.com/DotNetAnalyzers/StyleCopAnalyzers/master/StyleCop.Analyzers/StyleCop.Analyzers/Settings/stylecop.schema.json",
   "settings": {
     "documentationRules": {
       "documentInterfaces": true,
       "documentInternalMembers": false    
   }
  }
 }

3) the following under the buildOptions node in the project.json file:

  "additionalArguments": ["/additionalfile:path/to/stylecop.json" ]

but i got some errors: what is the problem?

Answer 1

Short Answer

Those NullReferenceException errors happen when StyleCop cannot find your stylecop.json. Here is the related GitHub issue.

To fix it (assuming that your stylecop.json is in the root of your project) change the path to this:

"additionalArguments": [
  "/additionalfile:./stylecop.json"
]

Full Working Example

Directory structure

bin
obj
Program.cs
project.json
project.lock.json
stylecop.json
StyleCop.ruleset

Project.json

{
  "version": "1.0.0-*",
  "buildOptions": {
    "debugType": "portable",
    "emitEntryPoint": true,
    "warningsAsErrors": true,
    "nowarn": [
      "1591"
    ],
    "xmlDoc": true,
    "additionalArguments": [
      "/ruleset:./StyleCop.ruleset",
      "/additionalfile:./stylecop.json"   <----- This is probably the problem.
    ]
  },
  "dependencies": {
    "StyleCop.Analyzers": {
      "type": "build",
      "version": "1.0.0"
    }
  },
  "frameworks": {
    "netcoreapp1.0": {
      "dependencies": {
        "Microsoft.NETCore.App": {
          "type": "platform",
          "version": "1.0.1"
        }
      }
    }
  }
}

stylecop.json

{
  "$schema": "https://raw.githubusercontent.com/DotNetAnalyzers/StyleCopAnalyzers/master/StyleCop.Analyzers/StyleCop.Analyzers/Settings/stylecop.schema.json",
  "settings": {
    "documentationRules": {
      "documentExposedElements": false,
      "documentInterfaces": false
    }
  }
}

StyleCop.ruleset

<?xml version="1.0" encoding="utf-8"?>
<RuleSet Name="New Rule Set" Description=" " ToolsVersion="14.0">
  <Rules AnalyzerId="StyleCop.Analyzers" RuleNamespace="StyleCop.Analyzers">
    <Rule Id="SA0000" Action="Warning" />
    <Rule Id="SA1005" Action="Warning" />
    <Rule Id="SA1208" Action="Warning" />
    <Rule Id="SA1028" Action="Warning" />
    <Rule Id="SA1210" Action="Warning" />
  </Rules>
</RuleSet>

Clone and Run the Example

git clone git@github.com:bigfont/StackOverflow.git
cd .\StackOverflow\AspNetCoreStyleCop\
dotnet restore
dotnet build