map.go

package devstatscode

import (
	"sort"
	"strings"
)

// SkipEmpty - skip one element arrays contining only empty string
// This is what strings.Split() returns for empty input
// We expect empty array or empty map returned in such cases
func SkipEmpty(arr []string) []string {
	if len(arr) != 1 || len(arr) == 1 && arr[0] != "" {
		return arr
	}
	return []string{}
}

// StringsMapToArray this is a function that calls given function for all array items and returns array of items processed by this func
// Example call: lib.StringsMapToArray(func(x string) string { return strings.TrimSpace(x) }, []string{" a", " b ", "c "})
func StringsMapToArray(f func(string) string, strArr []string) []string {
	strArr = SkipEmpty(strArr)
	outArr := make([]string, len(strArr))
	for index, str := range strArr {
		outArr[index] = f(str)
	}
	return outArr
}

// StringsMapToSet this is a function that calls given function for all array items and returns set of items processed by this func
// Example call: lib.StringsMapToSet(func(x string) string { return strings.TrimSpace(x) }, []string{" a", " b ", "c "})
func StringsMapToSet(f func(string) string, strArr []string) map[string]struct{} {
	strArr = SkipEmpty(strArr)
	outSet := make(map[string]struct{})
	for _, str := range strArr {
		outSet[f(str)] = struct{}{}
	}
	return outSet
}

// StringsSetKeys - returns all keys from string map
func StringsSetKeys(set map[string]struct{}) []string {
	outArr := make([]string, len(set))
	index := 0
	for key := range set {
		outArr[index] = key
		index++
	}
	sort.Strings(outArr)
	return outArr
}

// MapFromString - returns maps from string formatted as map[k1:v1 k2:v2 k3:v3 ...]
func MapFromString(str string) map[string]string {
	if len(str) < 6 {
		return nil
	}
	l := len(str)
	if str[:4] != "map[" || str[l-1:l] != "]" {
		return nil
	}
	str = str[4 : l-1]
	ary := strings.Split(str, " ")
	var res map[string]string
	for _, data := range ary {
		d := strings.Split(data, ":")
		if len(d) == 2 {
			if res == nil {
				res = make(map[string]string)
			}
			res[d[0]] = d[1]
		}
	}
	return res
}