golangci-lint: support autofix

[seaneagan]

Is your feature request related to a problem? Please describe.
golangci-lint supports a --fix option, but it's not supported by megalinter:
https://golangci-lint.run/usage/configuration/#command-line-options

Describe the solution you'd like
APPLY_FIXES against GO_GOLANGCI_LINT results in golangci-lint --fix ...

Describe alternatives you've considered

Running golangci-lint manually outside megalinter

[Kurt-von-Laven]

Sounds like a good idea. Feel free to open a pull request!

[echoix]

Since golang-ci is a Golang linter aggregator (compiled into one binary), and on their help page, they mention that the --fix option will work if it is supported by the linter, then for the tests file, we should find an error that is fixable by one of the linters to test that the option works when provided by MegaLinter.

Ie: it's possible that our test files for Go won't trigger a fix as is.

[nvuillam]

I share @Kurt-von-Laven & @echoix 's opinion, that would be a good improvement :)

@seaneagan do you have an example of error that could be autofixed in this file ? https://github.com/oxsecurity/megalinter/blob/main/.automation/test/golang/golang_good_01.go

[seaneagan]

@nvuillam the unused variable check is enabled by default, and autofixing will remove the line where the variable is defined, so that might be a good option

[nvuillam]

Well, we'll see what CI jobs say in #2683 :)

[nvuillam]

@seaneagan not working yet...

Maybe you could provide an example of file + example call ?
Is the fix just applied on the go file with --fix, or maybe it requires extra arguments ?

[Kurt-von-Laven]

The call itself looks right to me based on the docs, so I'm guessing we simply need a different example.

[seaneagan]

@nvuillam do the tests use one of these .golangci.yml's?

https://github.com/search?q=repo%3Aoxsecurity%2Fmegalinter%20path%3A*.golangci.yml&type=code

those don't match the golangci-lint's default config, which has the unused enabled: https://golangci-lint.run/usage/linters/#enabled-by-default:

it seems the git history of those files got lost in the superlinter > megalinter migration, but updating them to match the current default might make sense:

linters:
  disable-all: true
  enable:
    - gocritic
    - gosimple
    - govet
    - ineffassign
    - staticcheck
    - typecheck
    - unused

[seaneagan]

^ would also get rid of the deprecated linter usage (maligned, golint)

[nvuillam]

@seaneagan thanks, I try that :)

[nvuillam]

@seaneagan Still no fix with this update :/

https://github.com/oxsecurity/megalinter/actions/runs/5088248526/jobs/9144546351?pr=2683

Maybe you could try locally and provide the exact call and test file ?

[seaneagan]

sorry, i thought unused supported auto-fix but it doesn't, nor do any of the enabled by default linters. gofmt does though, so i'd suggest to add that to the list of linters in .golangci.yml.

Probably the most clear formatting mistake, which will get fixed by the above, will be to under-indent a line:

// This is a package comment
package main

import "fmt"

func nicolas() {
fmt.Println("hello world")
}

[nvuillam]

Thanks I try that :)

[nvuillam]

@seaneagan still KO :/

[seaneagan]

@nvuillam attempted to fix here: #2700

looks like it needs your approval to kick off the tests

[seaneagan]

@nvuillam #2700 looks good to go, it's based on #2683 so updating that one is fine too, either way.