encoder: add option to encode . and .. names

lib/encoder/encoder.go

@@ -92,8 +92,22 @@ func (mask MultiEncoder) Encode(in string) string {
 		encodeRightSpace     = uint(mask)&EncodeRightSpace != 0
 		encodeRightPeriod    = uint(mask)&EncodeRightPeriod != 0
 		encodeInvalidUnicode = uint(mask)&EncodeInvalidUtf8 != 0
+		encodeDot            = uint(mask)&EncodeDot != 0
 	)
 
+	if encodeDot {
+		switch in {
+		case ".":
+			return "．"
+		case "..":
+			return "．．"
+		case "．":
+			return string(QuoteRune) + "．"
+		case "．．":
+			return string(QuoteRune) + "．" + string(QuoteRune) + "．"
+		}
+	}
+
 	// handle prefix only replacements
 	prefix := ""
 	if encodeLeftSpace && len(in) > 0 { // Leading SPACE
@@ -299,8 +313,22 @@ func (mask MultiEncoder) Decode(in string) string {
 		encodeRightSpace     = uint(mask)&EncodeRightSpace != 0
 		encodeRightPeriod    = uint(mask)&EncodeRightPeriod != 0
 		encodeInvalidUnicode = uint(mask)&EncodeInvalidUtf8 != 0
+		encodeDot            = uint(mask)&EncodeDot != 0
 	)
 
+	if encodeDot {
+		switch in {
+		case "．":
+			return "."
+		case "．．":
+			return ".."
+		case string(QuoteRune) + "．":
+			return "．"
+		case string(QuoteRune) + "．" + string(QuoteRune) + "．":
+			return "．．"
+		}
+	}
+
 	// handle prefix only replacements
 	prefix := ""
 	if r, l1 := utf8.DecodeRuneInString(in); encodeLeftSpace && r == '␠' { // SYMBOL FOR SPACE

lib/encoder/encoder_test.go

@@ -102,6 +102,49 @@ func TestEncodeInvalidUnicode(t *testing.T) {
 		})
 	}
 }
+
+func TestEncodeDot(t *testing.T) {
+	for i, tc := range []testCase{
+		{
+			mask: 0,
+			in:   ".",
+			out:  ".",
+		}, {
+			mask: EncodeDot,
+			in:   ".",
+			out:  "．",
+		}, {
+			mask: 0,
+			in:   "..",
+			out:  "..",
+		}, {
+			mask: EncodeDot,
+			in:   "..",
+			out:  "．．",
+		}, {
+			mask: EncodeDot,
+			in:   "...",
+			out:  "...",
+		}, {
+			mask: EncodeDot,
+			in:   ". .",
+			out:  ". .",
+		},
+	} {
+		e := MultiEncoder(tc.mask)
+		t.Run(strconv.FormatInt(int64(i), 10), func(t *testing.T) {
+			got := e.Encode(tc.in)
+			if got != tc.out {
+				t.Errorf("Encode(%q) want %q got %q", tc.in, tc.out, got)
+			}
+			got2 := e.Decode(got)
+			if got2 != tc.in {
+				t.Errorf("Decode(%q) want %q got %q", got, tc.in, got2)
+			}
+		})
+	}
+}
+
 func TestDecodeHalf(t *testing.T) {
 	for i, tc := range []testCase{
 		{