lang: funcs: core: net: Add more mac fmt functions

lang/funcs/core/net/macfmt_func.go

@@ -31,6 +31,10 @@ func init() {
 		T: types.NewType("func(a str) str"),
 		V: MacFmt,
 	})
+	simple.ModuleRegister(ModuleName, "oldmacfmt", &types.FuncValue{
+		T: types.NewType("func(a str) str"),
+		V: OldMacFmt,
+	})
 }
 
 // MacFmt takes a MAC address with hyphens and converts it to a format with
@@ -51,3 +55,22 @@ func MacFmt(input []types.Value) (types.Value, error) {
 		V: strings.Replace(mac, "-", ":", -1),
 	}, nil
 }
+
+// OldMacFmt takes a MAC address with colons and converts it to a format with
+// hyphens. This is the old deprecated style that nobody likes.
+func OldMacFmt(input []types.Value) (types.Value, error) {
+	mac := input[0].Str()
+
+	// Check if the MAC address is valid.
+	if len(mac) != len("00:00:00:00:00:00") {
+		return nil, fmt.Errorf("invalid MAC address length: %s", mac)
+	}
+	_, err := net.ParseMAC(mac)
+	if err != nil {
+		return nil, err
+	}
+
+	return &types.StrValue{
+		V: strings.Replace(mac, ":", "-", -1),
+	}, nil
+}

lang/funcs/core/net/macfmt_func_test.go

@@ -52,3 +52,33 @@ func TestMacFmt(t *testing.T) {
 		})
 	}
 }
+
+func TestOldMacFmt(t *testing.T) {
+	var tests = []struct {
+		name    string
+		in      string
+		out     string
+		wantErr bool
+	}{
+		{"Valid mac with hyphens", "01:23:45:67:89:AB", "01-23-45-67-89-AB", false},
+		{"Valid mac with colons", "01-23-45-67-89-AB", "01-23-45-67-89-AB", false},
+		{"Incorrect mac length with hyphens", "01-23-45-67-89-AB-01-23-45-67-89-AB", "01-23-45-67-89-AB-01-23-45-67-89-AB", true},
+		{"Invalid mac", "", "", true},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			m, err := OldMacFmt([]types.Value{&types.StrValue{V: tt.in}})
+			if (err != nil) != tt.wantErr {
+				t.Errorf("func MacFmt() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if m != nil {
+				if err := m.Cmp(&types.StrValue{V: tt.out}); err != nil {
+					t.Errorf("got %q, want %q", m.Value(), tt.out)
+				}
+			}
+		})
+	}
+}