Partial revert of 4d2c4af 'Improve template mechanism' (#439)

There were template functions which we defined and others started using.
Although we no longer want those functions, since others use them,
deleting them breaks our API.  Putting those (unused) functions back.

cobra.go

@@ -19,14 +19,21 @@ package cobra
 import (
 	"fmt"
 	"io"
+	"reflect"
+	"strconv"
 	"strings"
 	"text/template"
 	"unicode"
 )
 
 var templateFuncs = template.FuncMap{
-	"trimTrailingWhitespaces": trimTrailingWhitespaces,
+	"trim":                    strings.TrimSpace,
+	"trimRightSpace":          trimRightSpace,
+	"trimTrailingWhitespaces": trimRightSpace,
+	"appendIfNotPresent":      appendIfNotPresent,
 	"rpad":                    rpad,
+	"gt":                      Gt,
+	"eq":                      Eq,
 }
 
 var initializers []func()
@@ -59,10 +66,70 @@ func OnInitialize(y ...func()) {
 	initializers = append(initializers, y...)
 }
 
-func trimTrailingWhitespaces(s string) string {
+// FIXME Gt is unused by cobra and should be removed in a version 2. It exists only for compatibility with users of cobra.
+
+// Gt takes two types and checks whether the first type is greater than the second. In case of types Arrays, Chans,
+// Maps and Slices, Gt will compare their lengths. Ints are compared directly while strings are first parsed as
+// ints and then compared.
+func Gt(a interface{}, b interface{}) bool {
+	var left, right int64
+	av := reflect.ValueOf(a)
+
+	switch av.Kind() {
+	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
+		left = int64(av.Len())
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		left = av.Int()
+	case reflect.String:
+		left, _ = strconv.ParseInt(av.String(), 10, 64)
+	}
+
+	bv := reflect.ValueOf(b)
+
+	switch bv.Kind() {
+	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
+		right = int64(bv.Len())
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		right = bv.Int()
+	case reflect.String:
+		right, _ = strconv.ParseInt(bv.String(), 10, 64)
+	}
+
+	return left > right
+}
+
+// FIXME Eq is unused by cobra and should be removed in a version 2. It exists only for compatibility with users of cobra.
+
+// Eq takes two types and checks whether they are equal. Supported types are int and string. Unsupported types will panic.
+func Eq(a interface{}, b interface{}) bool {
+	av := reflect.ValueOf(a)
+	bv := reflect.ValueOf(b)
+
+	switch av.Kind() {
+	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
+		panic("Eq called on unsupported type")
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return av.Int() == bv.Int()
+	case reflect.String:
+		return av.String() == bv.String()
+	}
+	return false
+}
+
+func trimRightSpace(s string) string {
 	return strings.TrimRightFunc(s, unicode.IsSpace)
 }
 
+// FIXME appendIfNotPresent is unused by cobra and should be removed in a version 2. It exists only for compatibility with users of cobra.
+
+// appendIfNotPresent will append stringToAppend to the end of s, but only if it's not yet present in s.
+func appendIfNotPresent(s, stringToAppend string) string {
+	if strings.Contains(s, stringToAppend) {
+		return s
+	}
+	return s + " " + stringToAppend
+}
+
 // rpad adds padding to the right of a string.
 func rpad(s string, padding int) string {
 	template := fmt.Sprintf("%%-%ds", padding)
@@ -71,8 +138,10 @@ func rpad(s string, padding int) string {
 
 // tmpl executes the given template text on data, writing the result to w.
 func tmpl(w io.Writer, text string, data interface{}) error {
-	t := template.New("top").Funcs(templateFuncs)
+	t := template.New("top")
-	return template.Must(t.Parse(text)).Execute(w, data)
+	t.Funcs(templateFuncs)
+	template.Must(t.Parse(text))
+	return t.Execute(w, data)
 }
 
 // ld compares two strings and returns the levenshtein distance between them.