Files
kong/options_test.go
Abhinav Gupta 3b9af5bdce feat: Support singleton providers (#501)
* feat: Support singleton providers

This change adds support for provider functions that are
not reinvoked even if requested by multiple other providers.
Instead, their value is cached and reused between invocations.

To make this possible, we change how bindings are stored:
instead of just a function reference, we now store a binding object
which records whether the binding is a singleton,
and records the resolved singleton value (if any).

Resolves #500

* refac(bindings): hide singleton status

Don't require callAnyFunction to be aware of
whether a binding is a singleton or not.
2025-02-17 17:44:03 +11:00

186 lines
3.8 KiB
Go

package kong
import (
"reflect"
"strings"
"testing"
"github.com/alecthomas/assert/v2"
)
func TestOptions(t *testing.T) {
var cli struct{}
p, err := New(&cli, Name("name"), Description("description"), Writers(nil, nil), Exit(nil))
assert.NoError(t, err)
assert.Equal(t, "name", p.Model.Name)
assert.Equal(t, "description", p.Model.Help)
assert.Zero(t, p.Stdout)
assert.Zero(t, p.Stderr)
assert.Zero(t, p.Exit)
}
type impl string
func (impl) Method() {}
func TestBindTo(t *testing.T) {
type iface interface {
Method()
}
saw := ""
method := func(i iface) error {
saw = string(i.(impl)) //nolint
return nil
}
var cli struct{}
p, err := New(&cli, BindTo(impl("foo"), (*iface)(nil)))
assert.NoError(t, err)
err = callFunction(reflect.ValueOf(method), p.bindings)
assert.NoError(t, err)
assert.Equal(t, "foo", saw)
}
func TestInvalidCallback(t *testing.T) {
type iface interface {
Method()
}
saw := ""
method := func(i iface) string {
saw = string(i.(impl)) //nolint
return saw
}
var cli struct{}
p, err := New(&cli, BindTo(impl("foo"), (*iface)(nil)))
assert.NoError(t, err)
err = callFunction(reflect.ValueOf(method), p.bindings)
assert.EqualError(t, err, `return value of func(kong.iface) string must implement "error"`)
}
type zrror struct{}
func (*zrror) Error() string {
return "error"
}
func TestCallbackCustomError(t *testing.T) {
type iface interface {
Method()
}
saw := ""
method := func(i iface) *zrror {
saw = string(i.(impl)) //nolint
return nil
}
var cli struct{}
p, err := New(&cli, BindTo(impl("foo"), (*iface)(nil)))
assert.NoError(t, err)
err = callFunction(reflect.ValueOf(method), p.bindings)
assert.NoError(t, err)
assert.Equal(t, "foo", saw)
}
type bindToProviderCLI struct {
Filled bool `default:"true"`
Called bool
Cmd bindToProviderCmd `cmd:""`
}
type boundThing struct {
Filled bool
}
type bindToProviderCmd struct{}
func (*bindToProviderCmd) Run(cli *bindToProviderCLI, b *boundThing) error {
cli.Called = true
return nil
}
func TestBindToProvider(t *testing.T) {
var cli bindToProviderCLI
app, err := New(&cli, BindToProvider(func(cli *bindToProviderCLI) (*boundThing, error) {
assert.True(t, cli.Filled, "CLI struct should have already been populated by Kong")
return &boundThing{Filled: cli.Filled}, nil
}))
assert.NoError(t, err)
ctx, err := app.Parse([]string{"cmd"})
assert.NoError(t, err)
err = ctx.Run()
assert.NoError(t, err)
assert.True(t, cli.Called)
}
func TestBindSingletonProvider(t *testing.T) {
type (
Connection struct{}
ClientA struct{ conn *Connection }
ClientB struct{ conn *Connection }
)
var numConnections int
newConnection := func() *Connection {
numConnections++
return &Connection{}
}
var cli struct{}
app, err := New(&cli,
BindSingletonProvider(newConnection),
BindToProvider(func(conn *Connection) *ClientA {
return &ClientA{conn: conn}
}),
BindToProvider(func(conn *Connection) *ClientB {
return &ClientB{conn: conn}
}),
)
assert.NoError(t, err)
ctx, err := app.Parse([]string{})
assert.NoError(t, err)
_, err = ctx.Call(func(a *ClientA, b *ClientB) {
assert.NotZero(t, a.conn)
assert.NotZero(t, b.conn)
assert.Equal(t, 1, numConnections, "expected newConnection to be called only once")
})
assert.NoError(t, err)
}
func TestFlagNamer(t *testing.T) {
var cli struct {
SomeFlag string
}
app, err := New(&cli, FlagNamer(strings.ToUpper))
assert.NoError(t, err)
assert.Equal(t, "SOMEFLAG", app.Model.Flags[1].Name)
}
type npError string
func (e npError) Error() string {
return "ERROR: " + string(e)
}
func TestCallbackNonPointerError(t *testing.T) {
method := func() error {
return npError("failed")
}
var cli struct{}
p, err := New(&cli)
assert.NoError(t, err)
err = callFunction(reflect.ValueOf(method), p.bindings)
assert.EqualError(t, err, "ERROR: failed")
}