diff.go

package utils

import (
	"fmt"
	"strings"
)

// PrintDiff pretty prints file differences.
//
// TODO(jlewi): We use this functionality across a lot of go packages; not just in kubeflow/kfctl but in other
// repos like kubeflow/testing. We should think about moving it into its own go module so it can be easily reused.
func PrintDiff(actual string, expected string) {
	sE, maxLen := convertToArray(expected)
	sA, _ := convertToArray(actual)
	format := fmt.Sprintf("%%s  %%-%ds %%s\n", maxLen+4)
	limit := 0
	if len(sE) < len(sA) {
		limit = len(sE)
	} else {
		limit = len(sA)
	}
	fmt.Printf(format, " ", "EXPECTED", "ACTUAL")
	fmt.Printf(format, " ", "--------", "------")
	for i := 0; i < limit; i++ {
		fmt.Printf(format, hint(sE[i], sA[i]), sE[i], sA[i])
	}
	if len(sE) < len(sA) {
		for i := len(sE); i < len(sA); i++ {
			fmt.Printf(format, "X", "", sA[i])
		}
	} else {
		for i := len(sA); i < len(sE); i++ {
			fmt.Printf(format, "X", sE[i], "")
		}
	}
}

func tabToSpace(input string) string {
	var result []string
	for _, i := range input {
		if i == 9 {
			result = append(result, "  ")
		} else {
			result = append(result, string(i))
		}
	}
	return strings.Join(result, "")
}

func convertToArray(x string) ([]string, int) {
	a := strings.Split(strings.TrimSuffix(x, "\n"), "\n")
	maxLen := 0
	for i, v := range a {
		z := tabToSpace(v)
		if len(z) > maxLen {
			maxLen = len(z)
		}
		a[i] = z
	}
	return a, maxLen
}

func hint(a, b string) string {
	if a == b {
		return " "
	}
	return "X"
}