Switch to ginkgo/gomega for tests

This switches over to ginkgo/gomega for tests, which makes writing
certain tests easier/more fluent in the future.

vendor/github.com/onsi/ginkgo/internal/codelocation/code_location.go

@@ -0,0 +1,32 @@
+package codelocation
+
+import (
+	"regexp"
+	"runtime"
+	"runtime/debug"
+	"strings"
+
+	"github.com/onsi/ginkgo/types"
+)
+
+func New(skip int) types.CodeLocation {
+	_, file, line, _ := runtime.Caller(skip + 1)
+	stackTrace := PruneStack(string(debug.Stack()), skip)
+	return types.CodeLocation{FileName: file, LineNumber: line, FullStackTrace: stackTrace}
+}
+
+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")
+}