func ErrorIs(expected error) TestDeep
ErrorIs operator reports whether any error in an error’s chain
matches expected.
_, err := os.Open("/unknown/file")
td.Cmp(t, err, os.ErrNotExist) // fails
td.Cmp(t, err, td.ErrorIs(os.ErrNotExist)) // succeeds
err1 := fmt.Errorf("failure1")
err2 := fmt.Errorf("failure2: %w", err1)
err3 := fmt.Errorf("failure3: %w", err2)
err := fmt.Errorf("failure4: %w", err3)
td.Cmp(t, err, td.ErrorIs(err)) // succeeds
td.Cmp(t, err, td.ErrorIs(err1)) // succeeds
td.Cmp(t, err1, td.ErrorIs(err)) // fails
Behind the scene it uses errors.Is function.
Note that like errors.Is, expected can be nil: in this case the
comparison succeeds when got is nil too.
See also
CmpErrorandCmpNoError.
See also ErrorIs godoc.
func CmpErrorIs(t TestingT, got any, expected error, args ...any) bool
CmpErrorIs is a shortcut for:
td.Cmp(t, got, td.ErrorIs(expected), 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 CmpErrorIs godoc.
func (t *T) CmpErrorIs(got any, expected error, args ...any) bool
CmpErrorIs is a shortcut for:
t.Cmp(got, td.ErrorIs(expected), args...)
See above for details.
Returns true if the test is OK, false if it fails.
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 T.CmpErrorIs godoc.