v3: how to combine env var and file sources?

[pat-s]

In v2 one could write

		EnvVars:  []string{"<var>"},
		FilePath: os.Getenv("<var>"),

how would this translate into v3?

[dearchap]

https://cli.urfave.org/migrate-v2-to-v3/

Use value source chain

[pat-s]

Awesome, didn't catch that one in the docs even though I looked at the migration page 👍️

[pat-s]

Hm, the only way I could make the compiler happy was to do something like this:

Sources: func() cli.ValueSourceChain {
  envVars := cli.EnvVars("var")
  files := cli.Files(os.Getenv("var"))
  return cli.NewValueSourceChain(&envVars, &files)
}(),

can this be right?

[dearchap]

Use EnvVar and File instead of EnvVars and Files if it's just a single env

[ldez]

The example inside the migration guide doesn't compile.
I fixed it inside #2093

Sources: cli.NewValueSourceChain(
    cli.EnvVar("<var>"),
    cli.File(os.Getenv("<var>"),
),