Add a function to sanitize nicknames

pkg/xstring/to_readable.go

@@ -0,0 +1,20 @@
+package xstring
+
+import (
+	"strings"
+	"unicode"
+
+	"golang.org/x/text/unicode/norm"
+)
+
+func ToReadable(s string) string {
+	plain := norm.NFKD.String(s)
+	var b strings.Builder
+	for _, r := range plain {
+		// Remove symbols (unicode.Symbol), keep everything else (including foreign letters)
+		if !unicode.IsSymbol(r) {
+			b.WriteRune(r)
+		}
+	}
+	return strings.Trim(b.String(), " ,\t\n\r")
+}

pkg/xstring/to_readable_test.go

@@ -0,0 +1,28 @@
+package xstring
+
+import (
+	"testing"
+)
+
+func TestToReadable(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{"", ""},
+		{"Hello, world!", "Hello, world!"},
+		{"Café", "Café"},
+		{"e\u0301", "é"},
+		{"Go语言", "Go语言"},
+		{"𝔘𝔫𝔦𝔠𝔬𝔡𝔢", "Unicode"},
+		{"🥛 , 𝑚𝑖𝐼𝐊𝐞𝐔!+", "miIKeU!"},
+		{"𝕱𝖗𝖆𝖓ç𝖔𝖎𝖘𝖊 & Dᵢₑ𝘴ₑ 🇫🇷", "Françoise & Diese"},
+	}
+
+	for _, tt := range tests {
+		result := ToReadable(tt.input)
+		if result != tt.expected {
+			t.Errorf("ToReadable(%q) = %q; want %q", tt.input, result, tt.expected)
+		}
+	}
+}