tpl/strings: Add strings.ContainsNonSpace

tpl/strings/strings.go

@@ -20,6 +20,7 @@ import (
 	"html/template"
 	"regexp"
 	"strings"
+	"unicode"
 	"unicode/utf8"
 
 	"github.com/gohugoio/hugo/common/text"
@@ -160,6 +161,19 @@ func (ns *Namespace) ContainsAny(s, chars any) (bool, error) {
 	return strings.ContainsAny(ss, sc), nil
 }
 
+// ContainsNonSpace reports whether s contains any non-space characters as defined
+// by Unicode's White Space property,
+func (ns *Namespace) ContainsNonSpace(s any) bool {
+	ss := cast.ToString(s)
+
+	for _, r := range ss {
+		if !unicode.IsSpace(r) {
+			return true
+		}
+	}
+	return false
+}
+
 // HasPrefix tests whether the input s begins with prefix.
 func (ns *Namespace) HasPrefix(s, prefix any) (bool, error) {
 	ss, err := cast.ToStringE(s)

tpl/strings/strings_test.go

@@ -145,6 +145,27 @@ func TestContainsAny(t *testing.T) {
 	}
 }
 
+func TestContainsNonSpace(t *testing.T) {
+	t.Parallel()
+	c := qt.New(t)
+
+	for _, test := range []struct {
+		s      any
+		expect bool
+	}{
+		{"", false},
+		{" ", false},
+		{"        ", false},
+		{"\t", false},
+		{"\r", false},
+		{"a", true},
+		{"    a", true},
+		{"a\n", true},
+	} {
+		c.Assert(ns.ContainsNonSpace(test.s), qt.Equals, test.expect)
+	}
+}
+
 func TestCountRunes(t *testing.T) {
 	t.Parallel()
 	c := qt.New(t)