func Test_UseProviders(t *testing.T) {
a := assert.New(t)
provider := &faux.Provider{}
goth.UseProviders(provider)
a.Equal(len(goth.GetProviders()), 1)
a.Equal(goth.GetProviders()[provider.Name()], provider)
goth.ClearProviders()
}
func Test_GetProvider(t *testing.T) {
a := assert.New(t)
provider := &faux.Provider{}
goth.UseProviders(provider)
p, err := goth.GetProvider(provider.Name())
a.NoError(err)
a.Equal(p, provider)
p, err = goth.GetProvider("unknown")
a.Error(err)
a.Equal(err.Error(), "no provider for unknown exists")
goth.ClearProviders()
}