github.com/onsi/gomega@v1.32.0/gstruct/pointer.go (about)

     1  // untested sections: 3
     2  
     3  package gstruct
     4  
     5  import (
     6  	"fmt"
     7  	"reflect"
     8  
     9  	"github.com/onsi/gomega/format"
    10  	"github.com/onsi/gomega/types"
    11  )
    12  
    13  //PointTo applies the given matcher to the value pointed to by actual. It fails if the pointer is
    14  //nil.
    15  //  actual := 5
    16  //  Expect(&actual).To(PointTo(Equal(5)))
    17  func PointTo(matcher types.GomegaMatcher) types.GomegaMatcher {
    18  	return &PointerMatcher{
    19  		Matcher: matcher,
    20  	}
    21  }
    22  
    23  type PointerMatcher struct {
    24  	Matcher types.GomegaMatcher
    25  
    26  	// Failure message.
    27  	failure string
    28  }
    29  
    30  func (m *PointerMatcher) Match(actual interface{}) (bool, error) {
    31  	val := reflect.ValueOf(actual)
    32  
    33  	// return error if actual type is not a pointer
    34  	if val.Kind() != reflect.Ptr {
    35  		return false, fmt.Errorf("PointerMatcher expects a pointer but we have '%s'", val.Kind())
    36  	}
    37  
    38  	if !val.IsValid() || val.IsNil() {
    39  		m.failure = format.Message(actual, "not to be <nil>")
    40  		return false, nil
    41  	}
    42  
    43  	// Forward the value.
    44  	elem := val.Elem().Interface()
    45  	match, err := m.Matcher.Match(elem)
    46  	if !match {
    47  		m.failure = m.Matcher.FailureMessage(elem)
    48  	}
    49  	return match, err
    50  }
    51  
    52  func (m *PointerMatcher) FailureMessage(_ interface{}) (message string) {
    53  	return m.failure
    54  }
    55  
    56  func (m *PointerMatcher) NegatedFailureMessage(actual interface{}) (message string) {
    57  	return m.Matcher.NegatedFailureMessage(actual)
    58  }