Nil

func Nil() TestDeep

Nil operator checks that data is nil (or is a non-nil interface, but containing a nil pointer.)

var got *int
td.Cmp(t, got, td.Nil())    // succeeds
td.Cmp(t, got, nil)         // fails as (*int)(nil) ≠ untyped nil
td.Cmp(t, got, (*int)(nil)) // succeeds

but:

var got fmt.Stringer = (*bytes.Buffer)(nil)
td.Cmp(t, got, td.Nil()) // succeeds
td.Cmp(t, got, nil)      // fails, as the interface is not nil
got = nil
td.Cmp(t, got, nil) // succeeds

See also Empty, NotNil and Zero.

See also Nil godoc.

Example

Base example

	t := &testing.T{}

	var got fmt.Stringer // interface

	// nil value can be compared directly with nil, no need of Nil() here
	ok := td.Cmp(t, got, nil)
	fmt.Println(ok)

	// But it works with Nil() anyway
	ok = td.Cmp(t, got, td.Nil())
	fmt.Println(ok)

	got = (*bytes.Buffer)(nil)

	// In the case of an interface containing a nil pointer, comparing
	// with nil fails, as the interface is not nil
	ok = td.Cmp(t, got, nil)
	fmt.Println(ok)

	// In this case Nil() succeed
	ok = td.Cmp(t, got, td.Nil())
	fmt.Println(ok)

	// Output:
	// true
	// true
	// false
	// true

CmpNil shortcut

func CmpNil(t TestingT, got any, args ...any) bool

CmpNil is a shortcut for:

td.Cmp(t, got, td.Nil(), args...)

See above for details.

Returns true if the test is OK, false if it fails.

If t is a *T then its Config field is inherited.

args… are optional and allow to name the test. This name is used in case of failure to qualify the test. If len(args) > 1 and the first item of args is a string and contains a ‘%’ rune then fmt.Fprintf is used to compose the name, else args are passed to fmt.Fprint. Do not forget it is the name of the test, not the reason of a potential failure.

See also CmpNil godoc.

Example

Base example

	t := &testing.T{}

	var got fmt.Stringer // interface

	// nil value can be compared directly with nil, no need of Nil() here
	ok := td.Cmp(t, got, nil)
	fmt.Println(ok)

	// But it works with Nil() anyway
	ok = td.CmpNil(t, got)
	fmt.Println(ok)

	got = (*bytes.Buffer)(nil)

	// In the case of an interface containing a nil pointer, comparing
	// with nil fails, as the interface is not nil
	ok = td.Cmp(t, got, nil)
	fmt.Println(ok)

	// In this case Nil() succeed
	ok = td.CmpNil(t, got)
	fmt.Println(ok)

	// Output:
	// true
	// true
	// false
	// true

T.Nil shortcut

func (t *T) Nil(got any, args ...any) bool

Nil is a shortcut for:

t.Cmp(got, td.Nil(), args...)

See above for details.

Returns true if the test is OK, false if it fails.

See also T.Nil godoc.

Example

Base example

	t := td.NewT(&testing.T{})

	var got fmt.Stringer // interface

	// nil value can be compared directly with nil, no need of Nil() here
	ok := t.Cmp(got, nil)
	fmt.Println(ok)

	// But it works with Nil() anyway
	ok = t.Nil(got)
	fmt.Println(ok)

	got = (*bytes.Buffer)(nil)

	// In the case of an interface containing a nil pointer, comparing
	// with nil fails, as the interface is not nil
	ok = t.Cmp(got, nil)
	fmt.Println(ok)

	// In this case Nil() succeed
	ok = t.Nil(got)
	fmt.Println(ok)

	// Output:
	// true
	// true
	// false
	// true