oauth2-proxy/oauth2-proxy

package testutil

import (
    "errors"
    "fmt"
    "unicode"
    "unicode/utf8"

    "github.com/google/go-cmp/cmp"
    "github.com/google/go-cmp/cmp/cmpopts"
    "github.com/onsi/gomega/format"
    "github.com/onsi/gomega/types"
)

type optionsMatcher struct {
    Expected       interface{}
    CompareOptions []cmp.Option
}

func EqualOpts(expected interface{}) types.GomegaMatcher {
    ignoreUnexported := cmp.FilterPath(func(p cmp.Path) bool {
        sf, ok := p.Index(-1).(cmp.StructField)
        if !ok {
            return false
        }
        r, _ := utf8.DecodeRuneInString(sf.Name())
        return !unicode.IsUpper(r)
    }, cmp.Ignore())

    return &optionsMatcher{
        Expected:       expected,
        CompareOptions: []cmp.Option{ignoreUnexported, cmpopts.EquateEmpty()},
    }
}

func (matcher *optionsMatcher) Match(actual interface{}) (success bool, err error) {
    if actual == nil && matcher.Expected == nil {
        return false, errors.New("trying to compare <nil> to <nil>")
    }
    return cmp.Equal(actual, matcher.Expected, matcher.CompareOptions...), nil
}

func (matcher *optionsMatcher) FailureMessage(actual interface{}) (message string) {
    actualString, actualOK := actual.(string)
    expectedString, expectedOK := fmt.Sprintf("%v", matcher.Expected), true
    if actualOK && expectedOK {
        return format.MessageWithDiff(actualString, "to equal", expectedString)
    }

    return format.Message(actual, "to equal", matcher.Expected) +
        "\n\nDiff:\n" + format.IndentString(matcher.getDiff(actual), 1)
}

func (matcher *optionsMatcher) NegatedFailureMessage(actual interface{}) (message string) {

    return format.Message(actual, "not to equal", matcher.Expected) +
        "\n\nDiff:\n" + format.IndentString(matcher.getDiff(actual), 1)
}

func (matcher *optionsMatcher) getDiff(actual interface{}) string {
    return cmp.Diff(actual, matcher.Expected, matcher.CompareOptions...)
}