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: watcher_hub_test.go
    path of file: ./repos/learning/golang/practice/go-crontab/gopath/src/github.com/coreos/etcd/etcdserver/api/v2store
    
    the code of the file until where you have to start completion: // Copyright 2015 The etcd Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law o
    
func TestIsHidden(t *testing.T) {
	// watch at "/"
	// key is "/_foo", hidden to "/"
	// expected: hidden = true
	watch := "/"
	key := "/_foo"
	hidden := isHidden(watch, key)
	if !hidden {
		t.Fatalf("%v should be hidden to %v\n", key, watch)
	}

	// watch at "/_foo"
	// key is "/_foo", not hidden to "/_foo"
	// expected: hidden = false
	watch = "/_foo"
	hidden = isHidden(watch, key)
	if hidden {
		t.Fatalf("%v should not be hidden to %v\n", key, watch)
	}

	// watch at "/_foo/"
	// key is "/_foo/foo", not hidden to "/_foo"
	key = "/_foo/foo"
	hidden = isHidden(watch, key)
	if hidden {
		t.Fatalf("%v should not be hidden to %v\n", key, watch)
	}

	// watch at "/_foo/"
	// key is "/_foo/_foo", hidden to "/_foo"
	key = "/_foo/_foo"
	hidden = isHidden(watch, key)
	if !hidden {
		t.Fatalf("%v should be hidden to %v\n", key, watch)
	}

	// watch at "/_foo/foo"
	// key is "/_foo"
	watch = "_foo/foo"
	key = "/_foo/"
	hidden = isHidden(watch, key)
	if hidden {
		t.Fatalf("%v should not be hidden to %v\n", key, watch)
	}
}