Merge pull request #4 from PaulSonOfLars/paul/add-blockquote-formatting

Add basic blockquote formatting

md2htmlV2.go

@@ -4,6 +4,7 @@ import (
 	"html"
 	"sort"
 	"strings"
+	"unicode"
 )
 
 var defaultConverterV2 = ConverterV2{
@@ -42,20 +43,22 @@ func MD2HTMLButtonsV2(in string) (string, []ButtonV2) {
 }
 
 var chars = map[string]string{
-	"`":   "code",
-	"```": "pre",
-	"_":   "i",
-	"*":   "b",
-	"~":   "s",
-	"__":  "u",
-	"|":   "", // this is a placeholder for || to work
-	"||":  "span class=\"tg-spoiler\"",
-	"!":   "", // for emoji
-	"[":   "", // for links
-	"]":   "", // for links/emoji
-	"(":   "", // for links/emoji
-	")":   "", // for links/emoji
-	"\\":  "", // for escapes
+	"`":    "code",
+	"```":  "pre",
+	"_":    "i",
+	"*":    "b",
+	"~":    "s",
+	"__":   "u",
+	"|":    "", // this is a placeholder for || to work
+	"||":   "span class=\"tg-spoiler\"",
+	"!":    "", // for emoji
+	"[":    "", // for links
+	"]":    "", // for links/emoji
+	"(":    "", // for links/emoji
+	")":    "", // for links/emoji
+	"\\":   "", // for escapes
+	">": "blockquote",
+	"&":    "", // for blockquotes
 }
 
 var AllMarkdownV2Chars = func() []rune {
@@ -174,6 +177,47 @@ func (cv ConverterV2) md2html(in []rune, enableButtons bool) (string, []ButtonV2
 			nestedT, nestedB := cv.md2html(in[nStart:nEnd], enableButtons)
 			return out.String() + "<" + chars[item] + ">" + nestedT + "</" + closeSpans(chars[item]) + ">" + followT, append(nestedB, followB...)
 
+		case '&':
+			if !(i+3 < len(in) && in[i+1] == 'g' && in[i+2] == 't' && in[i+3] == ';') {
+				out.WriteRune(c)
+				continue
+			}
+
+			if !validBlockQuoteStart(in, i) {
+				out.WriteRune(c)
+				continue
+			}
+			nStart := i + 4
+			for unicode.IsSpace(in[nStart]) {
+				nStart++
+			}
+
+			nEnd := len(in)
+			var contents []rune // We store all the contents, minus the > characters, so we avoid double-html tags
+			lineStart := true
+			for j := i + 4; j < len(in); j++ {
+				if lineStart && in[j] == ' ' {
+					// Skip space chars at start of lines
+					continue
+				}
+
+				lineStart = in[j] == '\n'
+				contents = append(contents, in[j])
+
+				if in[j] == '\n' {
+					if j+4 < len(in) && in[j+1] == '&' && in[j+2] == 'g' && in[j+3] == 't' && in[j+4] == ';' {
+						j = j + 4 // skip '>' symbol
+						continue
+					}
+					nEnd = j
+					break
+				}
+			}
+
+			nestedT, nestedB := cv.md2html(contents, enableButtons)
+			followT, followB := cv.md2html(in[nEnd:], enableButtons)
+			return out.String() + "<blockquote>" + strings.TrimSpace(nestedT) + "</blockquote>" + followT, append(nestedB, followB...)
+
 		case '!':
 			if len(in) <= i+1 || in[i+1] != '[' {
 				out.WriteRune(c)
@@ -245,6 +289,20 @@ func (cv ConverterV2) md2html(in []rune, enableButtons bool) (string, []ButtonV2
 	return out.String(), nil
 }
 
+func validBlockQuoteStart(in []rune, i int) bool {
+	for j := i - 1; j >= 0; j-- {
+		if !unicode.IsSpace(in[j]) {
+			return false
+		}
+		if in[j] == '\n' {
+			return true
+		}
+	}
+
+	// Start of message; must be valid.
+	return true
+}
+
 func EscapeMarkdownV2(r []rune) string {
 	out := strings.Builder{}
 	for i, x := range r {

md2htmlV2_test.go

@@ -64,7 +64,13 @@ var basicMDv2 = []struct {
 	}, { // ensure that premium stickers can get converted
 		in:  `![👍](tg://emoji?id=5368324170671202286)`,
 		out: `<tg-emoji emoji-id="5368324170671202286">👍</tg-emoji>`,
-	}, {},
+	}, {
+		in:  "> quote",
+		out: "<blockquote>quote</blockquote>",
+	}, {
+		in:  ">multi\n> line",
+		out: "<blockquote>multi\nline</blockquote>",
+	},
 }
 
 func TestMD2HTMLV2Basic(t *testing.T) {
@@ -243,6 +249,15 @@ var md2HTMLV2Buttons = []struct {
 				SameLine: false,
 			},
 		},
+	}, {
+		in:  "text\n> quote\ntext",
+		out: "text\n<blockquote>quote</blockquote>\ntext",
+	}, {
+		in:  "> `code quote`",
+		out: "<blockquote><code>code quote</code></blockquote>",
+	}, {
+		in:  "```go\ntext\n> not quote\nmore text```",
+		out: "<pre><code class=\"language-go\">text\n&gt; not quote\nmore text</code></pre>",
 	},
 }
 

reverseV2.go

@@ -103,14 +103,17 @@ func (cv ConverterV2) reverse(in []rune, buttons []ButtonV2) (string, error) {
 				} else {
 					return "", fmt.Errorf("badly formatted anchor tag %q", tagContent)
 				}
+			case "blockquote":
+				out.WriteString(">" + strings.Join(strings.Split(nested, "\n"), "\n>"))
+
 			default:
 				return "", fmt.Errorf("unknown tag %q", tag)
 			}
 
 			prev = closingClose + 1
 			i = closingClose
 
-		case '\\', '_', '*', '~', '`', '[', ']', '(', ')': // these all need to be escaped to ensure we retain the same message
+		case '\\', '_', '*', '~', '`', '[', ']', '(', ')', '>': // these all need to be escaped to ensure we retain the same message
 			out.WriteString(html.UnescapeString(string(in[prev:i])))
 			out.WriteRune('\\')
 			out.WriteRune(in[i])

reverseV2_test.go

@@ -10,15 +10,19 @@ import (
 
 func TestReverseV2(t *testing.T) {
 	for _, test := range reverseTest {
-		out, err := tg_md2html.ReverseV2(tg_md2html.MD2HTMLV2(test), nil)
-		assert.NoError(t, err, "Error for:\n%s", test)
-		assert.Equal(t, tg_md2html.MD2HTMLV2(test), tg_md2html.MD2HTMLV2(out))
+		t.Run(test, func(t *testing.T) {
+			out, err := tg_md2html.ReverseV2(tg_md2html.MD2HTMLV2(test), nil)
+			assert.NoError(t, err, "Error for:\n%s", test)
+			assert.Equal(t, tg_md2html.MD2HTMLV2(test), tg_md2html.MD2HTMLV2(out))
+		})
 	}
 
 	for _, test := range append(append(basicMD, basicMDv2...), advancedMD...) {
-		out, err := tg_md2html.ReverseV2(tg_md2html.MD2HTMLV2(test.in), nil)
-		assert.NoError(t, err, "Error for:\n%s", test)
-		assert.Equal(t, tg_md2html.MD2HTMLV2(test.in), tg_md2html.MD2HTMLV2(out))
+		t.Run(test.in, func(t *testing.T) {
+			out, err := tg_md2html.ReverseV2(tg_md2html.MD2HTMLV2(test.in), nil)
+			assert.NoError(t, err, "Error for:\n%s", test)
+			assert.Equal(t, tg_md2html.MD2HTMLV2(test.in), tg_md2html.MD2HTMLV2(out))
+		})
 	}
 
 	for _, test := range []string{