can't use double quote in values passed inside a string slice

[dbenque]

When using a string slice StringSliceVar it is impossible to pass values with double quotes "

The reason is that a CSVReader is used in the implementation (here) and it does not support ".

One possible solution would be to give the ability to the user to set the LazyQuote mode on the reader.
https://pkg.go.dev/encoding/csv#Reader.LazyQuotes

I faced this problem as I was using a string slice to pass some small piece of json.

Here is a simple program to reproduce the problem:

package main

import (
	"github.com/spf13/pflag"
	"os"
)

func main() {
	fs := pflag.NewFlagSet("Example", pflag.PanicOnError)
	var ss []string
	fs.StringSliceVar(&ss, "slice", []string{}, "test slice")

	if err := fs.Parse(os.Args); err != nil {
		panic(err)
	}
}

To be launched with:

go run main.go --slice='{"delay":"6h"}'

or

go run cmd/test/main.go --slice="{\"delay\":\"6h\"}"

The result should be:

panic: invalid argument "{\"delay\":\"6h\"}" for "--slice" flag: parse error on line 1, column 2: bare " in non-quoted-field

[dbenque]

Workaround: if you can you don't plan to use a coma separated value, and you are ok to repeat the parameter multiple times on the command line, you can use the string array that does not attempt a CSV parsing (almost, it does not in the Set, but it does here)

Here is a sample that works:

func main() {
	fs := pflag.NewFlagSet("Example", pflag.PanicOnError)
	var ss []string
	fs.StringArrayVar(&ss, "array", []string{}, "test slice")

	if err := fs.Parse(os.Args); err != nil {
		panic(err)
	}
	fmt.Printf("%#v", ss)
}

with: go run cmd/test/main.go --array='{"delay":"6h"}' --array='{"delay":"8h"}'