fix: children length checks

parser/blockquote.go

@@ -42,7 +42,9 @@ func (*BlockquoteParser) Match(tokens []*tokenizer.Token) (ast.Node, int) {
 			size++ // NewLine.
 		}
 	}
-
+	if len(children) == 0 {
+		return nil, 0
+	}
 	return &ast.Blockquote{
 		Children: children,
 	}, size

parser/bold.go

@@ -44,7 +44,7 @@ func (*BoldParser) Match(tokens []*tokenizer.Token) (ast.Node, int) {
 
 	size := len(matchedTokens)
 	children, err := ParseInlineWithParsers(matchedTokens[2:size-2], []InlineParser{NewLinkParser(), NewTextParser()})
-	if err != nil {
+	if err != nil || len(children) == 0 {
 		return nil, 0
 	}
 	return &ast.Bold{

parser/bold_italic.go

@@ -42,8 +42,13 @@ func (*BoldItalicParser) Match(tokens []*tokenizer.Token) (ast.Node, int) {
 	}
 
 	size := len(matchedTokens)
+	contentTokens := matchedTokens[3 : size-3]
+	if len(contentTokens) == 0 {
+		return nil, 0
+	}
+
 	return &ast.BoldItalic{
 		Symbol:  prefixTokenType,
-		Content: tokenizer.Stringify(matchedTokens[3 : size-3]),
+		Content: tokenizer.Stringify(contentTokens),
 	}, size
 }

parser/bold_test.go

@@ -19,6 +19,10 @@ func TestBoldParser(t *testing.T) {
 			text: "*Hello world!",
 			bold: nil,
 		},
+		{
+			text: "****",
+			bold: nil,
+		},
 		{
 			text: "**Hello**",
 			bold: &ast.Bold{

parser/heading.go

@@ -36,7 +36,6 @@ func (*HeadingParser) Match(tokens []*tokenizer.Token) (ast.Node, int) {
 	if err != nil {
 		return nil, 0
 	}
-
 	return &ast.Heading{
 		Level:    level,
 		Children: children,

parser/ordered_list.go

@@ -34,7 +34,6 @@ func (*OrderedListParser) Match(tokens []*tokenizer.Token) (ast.Node, int) {
 	if len(contentTokens) == 0 {
 		return nil, 0
 	}
-
 	children, err := ParseInline(contentTokens)
 	if err != nil {
 		return nil, 0

parser/table.go

@@ -94,15 +94,27 @@ func (*TableParser) Match(tokens []*tokenizer.Token) (ast.Node, int) {
 
 	cols := len(tokenizer.Split(headerTokens, tokenizer.Pipe)) - 2
 	for _, t := range tokenizer.Split(headerTokens, tokenizer.Pipe)[1 : cols+1] {
-		header = append(header, tokenizer.Stringify(t[1:len(t)-1]))
+		if len(t) < 3 {
+			header = append(header, "")
+		} else {
+			header = append(header, tokenizer.Stringify(t[1:len(t)-1]))
+		}
 	}
 	for _, t := range tokenizer.Split(delimiterTokens, tokenizer.Pipe)[1 : cols+1] {
-		delimiter = append(delimiter, tokenizer.Stringify(t[1:len(t)-1]))
+		if len(t) < 3 {
+			delimiter = append(delimiter, "")
+		} else {
+			delimiter = append(delimiter, tokenizer.Stringify(t[1:len(t)-1]))
+		}
 	}
 	for _, row := range rows {
 		cells := make([]string, 0)
 		for _, t := range tokenizer.Split(row, tokenizer.Pipe)[1 : cols+1] {
-			cells = append(cells, tokenizer.Stringify(t[1:len(t)-1]))
+			if len(t) < 3 {
+				cells = append(cells, "")
+			} else {
+				cells = append(cells, tokenizer.Stringify(t[1:len(t)-1]))
+			}
 		}
 		rowsStr = append(rowsStr, cells)
 	}

parser/task_list.go

@@ -43,7 +43,6 @@ func (*TaskListParser) Match(tokens []*tokenizer.Token) (ast.Node, int) {
 	if len(contentTokens) == 0 {
 		return nil, 0
 	}
-
 	children, err := ParseInline(contentTokens)
 	if err != nil {
 		return nil, 0