You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: testing.go
    path of file: ./repos/skeema/vendor/github.com/skeema/mybase
    
    the code of the file until where you have to start completion: package mybase

import (
	"bytes"
	"testing"
	"unicode"
)

// This file contains exported methods and types that 
    
func ParseFakeCLI(t *testing.T, cmd *Command, commandLine string, sources ...OptionValuer) *Config {
	t.Helper()
	args := tokenizeCommandLine(t, commandLine)
	cfg, err := ParseCLI(cmd, args)
	if err != nil {
		t.Fatalf("ParseCLI returned unexpected error: %s", err)
	}
	for _, src := range sources {
		cfg.AddSource(src)
	}
	cfg.IsTest = true
	return cfg
}