Add the sprig functions in the template engine

vendor/github.com/Masterminds/sprig/list.go

@@ -0,0 +1,109 @@
+package sprig
+
+import (
+	"reflect"
+	"sort"
+)
+
+func list(v ...interface{}) []interface{} {
+	return v
+}
+
+func push(list []interface{}, v interface{}) []interface{} {
+	return append(list, v)
+}
+
+func prepend(list []interface{}, v interface{}) []interface{} {
+	return append([]interface{}{v}, list...)
+}
+
+func last(list []interface{}) interface{} {
+	l := len(list)
+	if l == 0 {
+		return nil
+	}
+	return list[l-1]
+}
+
+func first(list []interface{}) interface{} {
+	if len(list) == 0 {
+		return nil
+	}
+	return list[0]
+}
+
+func rest(list []interface{}) []interface{} {
+	if len(list) == 0 {
+		return list
+	}
+	return list[1:]
+}
+
+func initial(list []interface{}) []interface{} {
+	l := len(list)
+	if l == 0 {
+		return list
+	}
+	return list[:l-1]
+}
+
+func sortAlpha(list interface{}) []string {
+	k := reflect.Indirect(reflect.ValueOf(list)).Kind()
+	switch k {
+	case reflect.Slice, reflect.Array:
+		a := strslice(list)
+		s := sort.StringSlice(a)
+		s.Sort()
+		return s
+	}
+	return []string{strval(list)}
+}
+
+func reverse(v []interface{}) []interface{} {
+	// We do not sort in place because the incomming array should not be altered.
+	l := len(v)
+	c := make([]interface{}, l)
+	for i := 0; i < l; i++ {
+		c[l-i-1] = v[i]
+	}
+	return c
+}
+
+func compact(list []interface{}) []interface{} {
+	res := []interface{}{}
+	for _, item := range list {
+		if !empty(item) {
+			res = append(res, item)
+		}
+	}
+	return res
+}
+
+func uniq(list []interface{}) []interface{} {
+	dest := []interface{}{}
+	for _, item := range list {
+		if !inList(dest, item) {
+			dest = append(dest, item)
+		}
+	}
+	return dest
+}
+
+func inList(haystack []interface{}, needle interface{}) bool {
+	for _, h := range haystack {
+		if reflect.DeepEqual(needle, h) {
+			return true
+		}
+	}
+	return false
+}
+
+func without(list []interface{}, omit ...interface{}) []interface{} {
+	res := []interface{}{}
+	for _, i := range list {
+		if !inList(omit, i) {
+			res = append(res, i)
+		}
+	}
+	return res
+}