FilePath does not take precedence over EnvVar

[zc-devs]

My urfave/cli version is v2.27.1

Dependency Management

• I am unsure of what my dependency management setup is.

Describe the bug

FilePath does not take precedence over EnvVar as described in documentation.

To reproduce

1. Set some flag

   &cli.StringFlag{
   EnvVars:  []string{"WOODPECKER_DATABASE_DATASOURCE"},
   Name:     "datasource",
   Usage:    "database driver configuration string",
   Value:    "woodpecker.sqlite",
   FilePath: os.Getenv("WOODPECKER_DATABASE_DATASOURCE_FILE"),
   },

2. Set EnvVar:

   export WOODPECKER_DATABASE_DATASOURCE=/var/lib/woodpecker/woodpecker.sqlite

3. Set FilePath variable:

   export WOODPECKER_DATABASE_DATASOURCE_FILE=/run/secrets/woodpecker-datasource.conf

4. Get /var/lib/woodpecker/woodpecker.sqlite instead /run/secrets/woodpecker-datasource.conf in datasource flag.

Observed behavior

Step 4.

Expected behavior

FilePath should take precedence over EnvVar. So, I should get /run/secrets/woodpecker-datasource.conf in datasource flag.

Additional context

https://github.com/woodpecker-ci/woodpecker/issues/3389