quotecheck

Verify when safely escape and single quote strings on fmt.Sprintf.

This code is based on perfsprint analyzer.

Motivation

While it seems safe write '%s' to just delimit some string, it may have nasty consequences, like if the string already contains a quote char it add some surprises in our output. But go supports a better alternative: %q is defined as a single-quoted character literal safely escaped with Go syntax.

Instruction

go install github.com/peczenyj/fmtquotecheck/cmd/fmtquotecheck@latest

Usage

package main

import "fmt"

func main(){
    fmt.Printf("hello '%s'", "world") // we should use %q here 
}

$ fmtquotecheck ./main.go 
./main.go:6:16: explicit single-quoted '%s' should be replaced by `%q` in fmt.Printf

by using the option -fix the linter will convert all '%s' to %q.

CI

CircleCI

- run:
    name: install fmtquotecheck
    command: go install github.com/peczenyj/fmtquotecheck/cmd/fmtquotecheck@latest

- run:
    name: run fmtquotecheck
    command: fmtquotecheck ./...

GitHub Actions

- name: install fmtquotecheck
  run: go install github.com/peczenyj/fmtquotecheck/cmd/fmtquotecheck@latest

- name: run fmtquotecheck
  run: fmtquotecheck ./...