New linters

How to write a linter

Use go/analysis and take a look at this tutorial: it shows how to write go/analysis linter from scratch and integrate it into golangci-lint.

How to add a public linter to golangci-lint

You need to implement a new linter using go/analysis API.

We don’t accept non go/analysis linters.

After that:

1. Implement functional tests for the linter:
   • Add one file into directory pkg/golinters/{yourlintername}/testdata/.
2. Add a new file pkg/golinters/{yourlintername}/{yourlintername}.go. Other linters implementation can help you.
3. Add the new struct for the linter (which you’ve implemented in pkg/golinters/{yourlintername}/{yourlintername}.go) to the list of all supported linters in pkg/lint/lintersdb/builder_linter.go to the method LinterBuilder.Build.
   • Add WithSince("next_version"), where next_version must be replaced by the next minor version. (ex: v1.2.0 if the current version is v1.1.0)
4. Find out what options do you need to configure for the linter. For example, nakedret has only 1 option: max-func-lines. Choose default values to not being annoying for users of golangci-lint. Add configuration options to:
   • .golangci.next.reference.yml: the example of a configuration file. You can also add them to .golangci.yml if you think that this project needs not default values.
   • config struct: don’t forget about mapstructure tags for proper configuration files parsing.
5. Take a look at the example of pull requests with new linter support.
6. Run the tests:

   go run ./cmd/golangci-lint/ run --no-config --default=none --enable={yourlintername} ./pkg/golinters/{yourlintername}/testdata/{yourlintername}.go

How to add a private linter to golangci-lint

Some people and organizations may choose to have custom-made linters run as a part of golangci-lint.
Typically, these linters can’t be open-sourced or too specific.

Such linters can be added through 2 plugin systems: