POC

vendor/github.com/onsi/gomega/matchers/have_exact_elements.go

@@ -0,0 +1,83 @@
+package matchers
+
+import (
+	"fmt"
+
+	"github.com/onsi/gomega/format"
+)
+
+type mismatchFailure struct {
+	failure string
+	index   int
+}
+
+type HaveExactElementsMatcher struct {
+	Elements         []interface{}
+	mismatchFailures []mismatchFailure
+	missingIndex     int
+	extraIndex       int
+}
+
+func (matcher *HaveExactElementsMatcher) Match(actual interface{}) (success bool, err error) {
+	matcher.resetState()
+
+	if isMap(actual) {
+		return false, fmt.Errorf("error")
+	}
+
+	matchers := matchers(matcher.Elements)
+	values := valuesOf(actual)
+
+	lenMatchers := len(matchers)
+	lenValues := len(values)
+
+	for i := 0; i < lenMatchers || i < lenValues; i++ {
+		if i >= lenMatchers {
+			matcher.extraIndex = i
+			continue
+		}
+
+		if i >= lenValues {
+			matcher.missingIndex = i
+			return
+		}
+
+		elemMatcher := matchers[i].(omegaMatcher)
+		match, err := elemMatcher.Match(values[i])
+		if err != nil || !match {
+			matcher.mismatchFailures = append(matcher.mismatchFailures, mismatchFailure{
+				index:   i,
+				failure: elemMatcher.FailureMessage(values[i]),
+			})
+		}
+	}
+
+	return matcher.missingIndex+matcher.extraIndex+len(matcher.mismatchFailures) == 0, nil
+}
+
+func (matcher *HaveExactElementsMatcher) FailureMessage(actual interface{}) (message string) {
+	message = format.Message(actual, "to have exact elements with", presentable(matcher.Elements))
+	if matcher.missingIndex > 0 {
+		message = fmt.Sprintf("%s\nthe missing elements start from index %d", message, matcher.missingIndex)
+	}
+	if matcher.extraIndex > 0 {
+		message = fmt.Sprintf("%s\nthe extra elements start from index %d", message, matcher.extraIndex)
+	}
+	if len(matcher.mismatchFailures) != 0 {
+		message = fmt.Sprintf("%s\nthe mismatch indexes were:", message)
+	}
+	for _, mismatch := range matcher.mismatchFailures {
+		message = fmt.Sprintf("%s\n%d: %s", message, mismatch.index, mismatch.failure)
+	}
+	return
+}
+
+func (matcher *HaveExactElementsMatcher) NegatedFailureMessage(actual interface{}) (message string) {
+	return format.Message(actual, "not to contain elements", presentable(matcher.Elements))
+}
+
+func (matcher *HaveExactElementsMatcher) resetState() {
+	matcher.mismatchFailures = nil
+	matcher.missingIndex = 0
+	matcher.extraIndex = 0
+}