github.com/onsi/gomega@v1.32.0/matchers/have_value.go (about)

     1  package matchers
     2  
     3  import (
     4  	"errors"
     5  	"reflect"
     6  
     7  	"github.com/onsi/gomega/format"
     8  	"github.com/onsi/gomega/types"
     9  )
    10  
    11  const maxIndirections = 31
    12  
    13  type HaveValueMatcher struct {
    14  	Matcher        types.GomegaMatcher // the matcher to apply to the "resolved" actual value.
    15  	resolvedActual interface{}         // the ("resolved") value.
    16  }
    17  
    18  func (m *HaveValueMatcher) Match(actual interface{}) (bool, error) {
    19  	val := reflect.ValueOf(actual)
    20  	for allowedIndirs := maxIndirections; allowedIndirs > 0; allowedIndirs-- {
    21  		// return an error if value isn't valid. Please note that we cannot
    22  		// check for nil here, as we might not deal with a pointer or interface
    23  		// at this point.
    24  		if !val.IsValid() {
    25  			return false, errors.New(format.Message(
    26  				actual, "not to be <nil>"))
    27  		}
    28  		switch val.Kind() {
    29  		case reflect.Ptr, reflect.Interface:
    30  			// resolve pointers and interfaces to their values, then rinse and
    31  			// repeat.
    32  			if val.IsNil() {
    33  				return false, errors.New(format.Message(
    34  					actual, "not to be <nil>"))
    35  			}
    36  			val = val.Elem()
    37  			continue
    38  		default:
    39  			// forward the final value to the specified matcher.
    40  			m.resolvedActual = val.Interface()
    41  			return m.Matcher.Match(m.resolvedActual)
    42  		}
    43  	}
    44  	// too many indirections: extreme star gazing, indeed...?
    45  	return false, errors.New(format.Message(actual, "too many indirections"))
    46  }
    47  
    48  func (m *HaveValueMatcher) FailureMessage(_ interface{}) (message string) {
    49  	return m.Matcher.FailureMessage(m.resolvedActual)
    50  }
    51  
    52  func (m *HaveValueMatcher) NegatedFailureMessage(_ interface{}) (message string) {
    53  	return m.Matcher.NegatedFailureMessage(m.resolvedActual)
    54  }