Add simple testing infrastructure

vendor/github.com/onsi/gomega/internal/testingtsupport/testing_t_support.go

@@ -0,0 +1,40 @@
+package testingtsupport
+
+import (
+	"regexp"
+	"runtime/debug"
+	"strings"
+
+	"github.com/onsi/gomega/types"
+)
+
+type gomegaTestingT interface {
+	Errorf(format string, args ...interface{})
+}
+
+func BuildTestingTGomegaFailHandler(t gomegaTestingT) types.GomegaFailHandler {
+	return func(message string, callerSkip ...int) {
+		skip := 1
+		if len(callerSkip) > 0 {
+			skip = callerSkip[0]
+		}
+		stackTrace := pruneStack(string(debug.Stack()), skip)
+		t.Errorf("\n%s\n%s", stackTrace, message)
+	}
+}
+
+func pruneStack(fullStackTrace string, skip int) string {
+	stack := strings.Split(fullStackTrace, "\n")
+	if len(stack) > 2*(skip+1) {
+		stack = stack[2*(skip+1):]
+	}
+	prunedStack := []string{}
+	re := regexp.MustCompile(`\/ginkgo\/|\/pkg\/testing\/|\/pkg\/runtime\/`)
+	for i := 0; i < len(stack)/2; i++ {
+		if !re.Match([]byte(stack[i*2])) {
+			prunedStack = append(prunedStack, stack[i*2])
+			prunedStack = append(prunedStack, stack[i*2+1])
+		}
+	}
+	return strings.Join(prunedStack, "\n")
+}