mirror of
https://github.com/cwinfo/matterbridge.git
synced 2024-11-10 11:00:27 +00:00
1988 lines
42 KiB
Go
1988 lines
42 KiB
Go
package parser
|
|
|
|
import (
|
|
"bytes"
|
|
"html"
|
|
"regexp"
|
|
"strconv"
|
|
"unicode"
|
|
|
|
"github.com/gomarkdown/markdown/ast"
|
|
)
|
|
|
|
// Parsing block-level elements.
|
|
|
|
const (
|
|
charEntity = "&(?:#x[a-f0-9]{1,8}|#[0-9]{1,8}|[a-z][a-z0-9]{1,31});"
|
|
escapable = "[!\"#$%&'()*+,./:;<=>?@[\\\\\\]^_`{|}~-]"
|
|
)
|
|
|
|
var (
|
|
reBackslashOrAmp = regexp.MustCompile("[\\&]")
|
|
reEntityOrEscapedChar = regexp.MustCompile("(?i)\\\\" + escapable + "|" + charEntity)
|
|
|
|
// blockTags is a set of tags that are recognized as HTML block tags.
|
|
// Any of these can be included in markdown text without special escaping.
|
|
blockTags = map[string]struct{}{
|
|
"blockquote": {},
|
|
"del": {},
|
|
"dd": {},
|
|
"div": {},
|
|
"dl": {},
|
|
"dt": {},
|
|
"fieldset": {},
|
|
"form": {},
|
|
"h1": {},
|
|
"h2": {},
|
|
"h3": {},
|
|
"h4": {},
|
|
"h5": {},
|
|
"h6": {},
|
|
// TODO: technically block but breaks Inline HTML (Simple).text
|
|
//"hr": {},
|
|
"iframe": {},
|
|
"ins": {},
|
|
"li": {},
|
|
"math": {},
|
|
"noscript": {},
|
|
"ol": {},
|
|
"pre": {},
|
|
"p": {},
|
|
"script": {},
|
|
"style": {},
|
|
"table": {},
|
|
"ul": {},
|
|
|
|
// HTML5
|
|
"address": {},
|
|
"article": {},
|
|
"aside": {},
|
|
"canvas": {},
|
|
"details": {},
|
|
"dialog": {},
|
|
"figcaption": {},
|
|
"figure": {},
|
|
"footer": {},
|
|
"header": {},
|
|
"hgroup": {},
|
|
"main": {},
|
|
"nav": {},
|
|
"output": {},
|
|
"progress": {},
|
|
"section": {},
|
|
"video": {},
|
|
}
|
|
)
|
|
|
|
// sanitizeAnchorName returns a sanitized anchor name for the given text.
|
|
// Taken from https://github.com/shurcooL/sanitized_anchor_name/blob/master/main.go#L14:1
|
|
func sanitizeAnchorName(text string) string {
|
|
var anchorName []rune
|
|
var futureDash = false
|
|
for _, r := range text {
|
|
switch {
|
|
case unicode.IsLetter(r) || unicode.IsNumber(r):
|
|
if futureDash && len(anchorName) > 0 {
|
|
anchorName = append(anchorName, '-')
|
|
}
|
|
futureDash = false
|
|
anchorName = append(anchorName, unicode.ToLower(r))
|
|
default:
|
|
futureDash = true
|
|
}
|
|
}
|
|
return string(anchorName)
|
|
}
|
|
|
|
// Parse block-level data.
|
|
// Note: this function and many that it calls assume that
|
|
// the input buffer ends with a newline.
|
|
func (p *Parser) block(data []byte) {
|
|
// this is called recursively: enforce a maximum depth
|
|
if p.nesting >= p.maxNesting {
|
|
return
|
|
}
|
|
p.nesting++
|
|
|
|
// parse out one block-level construct at a time
|
|
for len(data) > 0 {
|
|
// attributes that can be specific before a block element:
|
|
//
|
|
// {#id .class1 .class2 key="value"}
|
|
if p.extensions&Attributes != 0 {
|
|
data = p.attribute(data)
|
|
}
|
|
|
|
if p.extensions&Includes != 0 {
|
|
f := p.readInclude
|
|
path, address, consumed := p.isInclude(data)
|
|
if consumed == 0 {
|
|
path, address, consumed = p.isCodeInclude(data)
|
|
f = p.readCodeInclude
|
|
}
|
|
if consumed > 0 {
|
|
included := f(p.includeStack.Last(), path, address)
|
|
p.includeStack.Push(path)
|
|
p.block(included)
|
|
p.includeStack.Pop()
|
|
data = data[consumed:]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// user supplied parser function
|
|
if p.Opts.ParserHook != nil {
|
|
node, blockdata, consumed := p.Opts.ParserHook(data)
|
|
if consumed > 0 {
|
|
data = data[consumed:]
|
|
|
|
if node != nil {
|
|
p.addBlock(node)
|
|
if blockdata != nil {
|
|
p.block(blockdata)
|
|
p.finalize(node)
|
|
}
|
|
}
|
|
continue
|
|
}
|
|
}
|
|
|
|
// prefixed heading:
|
|
//
|
|
// # Heading 1
|
|
// ## Heading 2
|
|
// ...
|
|
// ###### Heading 6
|
|
if p.isPrefixHeading(data) {
|
|
data = data[p.prefixHeading(data):]
|
|
continue
|
|
}
|
|
|
|
// prefixed special heading:
|
|
// (there are no levels.)
|
|
//
|
|
// .# Abstract
|
|
if p.isPrefixSpecialHeading(data) {
|
|
data = data[p.prefixSpecialHeading(data):]
|
|
continue
|
|
}
|
|
|
|
// block of preformatted HTML:
|
|
//
|
|
// <div>
|
|
// ...
|
|
// </div>
|
|
if data[0] == '<' {
|
|
if i := p.html(data, true); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// title block
|
|
//
|
|
// % stuff
|
|
// % more stuff
|
|
// % even more stuff
|
|
if p.extensions&Titleblock != 0 {
|
|
if data[0] == '%' {
|
|
if i := p.titleBlock(data, true); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
|
|
// blank lines. note: returns the # of bytes to skip
|
|
if i := p.isEmpty(data); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
|
|
// indented code block:
|
|
//
|
|
// func max(a, b int) int {
|
|
// if a > b {
|
|
// return a
|
|
// }
|
|
// return b
|
|
// }
|
|
if p.codePrefix(data) > 0 {
|
|
data = data[p.code(data):]
|
|
continue
|
|
}
|
|
|
|
// fenced code block:
|
|
//
|
|
// ``` go
|
|
// func fact(n int) int {
|
|
// if n <= 1 {
|
|
// return n
|
|
// }
|
|
// return n * fact(n-1)
|
|
// }
|
|
// ```
|
|
if p.extensions&FencedCode != 0 {
|
|
if i := p.fencedCodeBlock(data, true); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// horizontal rule:
|
|
//
|
|
// ------
|
|
// or
|
|
// ******
|
|
// or
|
|
// ______
|
|
if p.isHRule(data) {
|
|
i := skipUntilChar(data, 0, '\n')
|
|
hr := ast.HorizontalRule{}
|
|
hr.Literal = bytes.Trim(data[:i], " \n")
|
|
p.addBlock(&hr)
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
|
|
// block quote:
|
|
//
|
|
// > A big quote I found somewhere
|
|
// > on the web
|
|
if p.quotePrefix(data) > 0 {
|
|
data = data[p.quote(data):]
|
|
continue
|
|
}
|
|
|
|
// aside:
|
|
//
|
|
// A> The proof is too large to fit
|
|
// A> in the margin.
|
|
if p.extensions&Mmark != 0 {
|
|
if p.asidePrefix(data) > 0 {
|
|
data = data[p.aside(data):]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// figure block:
|
|
//
|
|
// !---
|
|
// 
|
|
// 
|
|
// !---
|
|
if p.extensions&Mmark != 0 {
|
|
if i := p.figureBlock(data, true); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// table:
|
|
//
|
|
// Name | Age | Phone
|
|
// ------|-----|---------
|
|
// Bob | 31 | 555-1234
|
|
// Alice | 27 | 555-4321
|
|
if p.extensions&Tables != 0 {
|
|
if i := p.table(data); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// an itemized/unordered list:
|
|
//
|
|
// * Item 1
|
|
// * Item 2
|
|
//
|
|
// also works with + or -
|
|
if p.uliPrefix(data) > 0 {
|
|
data = data[p.list(data, 0, 0):]
|
|
continue
|
|
}
|
|
|
|
// a numbered/ordered list:
|
|
//
|
|
// 1. Item 1
|
|
// 2. Item 2
|
|
if i := p.oliPrefix(data); i > 0 {
|
|
start := 0
|
|
if i > 2 && p.extensions&OrderedListStart != 0 {
|
|
s := string(data[:i-2])
|
|
start, _ = strconv.Atoi(s)
|
|
if start == 1 {
|
|
start = 0
|
|
}
|
|
}
|
|
data = data[p.list(data, ast.ListTypeOrdered, start):]
|
|
continue
|
|
}
|
|
|
|
// definition lists:
|
|
//
|
|
// Term 1
|
|
// : Definition a
|
|
// : Definition b
|
|
//
|
|
// Term 2
|
|
// : Definition c
|
|
if p.extensions&DefinitionLists != 0 {
|
|
if p.dliPrefix(data) > 0 {
|
|
data = data[p.list(data, ast.ListTypeDefinition, 0):]
|
|
continue
|
|
}
|
|
}
|
|
|
|
if p.extensions&MathJax != 0 {
|
|
if i := p.blockMath(data); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// document matters:
|
|
//
|
|
// {frontmatter}/{mainmatter}/{backmatter}
|
|
if p.extensions&Mmark != 0 {
|
|
if i := p.documentMatter(data); i > 0 {
|
|
data = data[i:]
|
|
continue
|
|
}
|
|
}
|
|
|
|
// anything else must look like a normal paragraph
|
|
// note: this finds underlined headings, too
|
|
idx := p.paragraph(data)
|
|
data = data[idx:]
|
|
}
|
|
|
|
p.nesting--
|
|
}
|
|
|
|
func (p *Parser) addBlock(n ast.Node) ast.Node {
|
|
p.closeUnmatchedBlocks()
|
|
|
|
if p.attr != nil {
|
|
if c := n.AsContainer(); c != nil {
|
|
c.Attribute = p.attr
|
|
}
|
|
if l := n.AsLeaf(); l != nil {
|
|
l.Attribute = p.attr
|
|
}
|
|
p.attr = nil
|
|
}
|
|
return p.addChild(n)
|
|
}
|
|
|
|
func (p *Parser) isPrefixHeading(data []byte) bool {
|
|
if data[0] != '#' {
|
|
return false
|
|
}
|
|
|
|
if p.extensions&SpaceHeadings != 0 {
|
|
level := skipCharN(data, 0, '#', 6)
|
|
if level == len(data) || data[level] != ' ' {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
func (p *Parser) prefixHeading(data []byte) int {
|
|
level := skipCharN(data, 0, '#', 6)
|
|
i := skipChar(data, level, ' ')
|
|
end := skipUntilChar(data, i, '\n')
|
|
skip := end
|
|
id := ""
|
|
if p.extensions&HeadingIDs != 0 {
|
|
j, k := 0, 0
|
|
// find start/end of heading id
|
|
for j = i; j < end-1 && (data[j] != '{' || data[j+1] != '#'); j++ {
|
|
}
|
|
for k = j + 1; k < end && data[k] != '}'; k++ {
|
|
}
|
|
// extract heading id iff found
|
|
if j < end && k < end {
|
|
id = string(data[j+2 : k])
|
|
end = j
|
|
skip = k + 1
|
|
for end > 0 && data[end-1] == ' ' {
|
|
end--
|
|
}
|
|
}
|
|
}
|
|
for end > 0 && data[end-1] == '#' {
|
|
if isBackslashEscaped(data, end-1) {
|
|
break
|
|
}
|
|
end--
|
|
}
|
|
for end > 0 && data[end-1] == ' ' {
|
|
end--
|
|
}
|
|
if end > i {
|
|
if id == "" && p.extensions&AutoHeadingIDs != 0 {
|
|
id = sanitizeAnchorName(string(data[i:end]))
|
|
}
|
|
block := &ast.Heading{
|
|
HeadingID: id,
|
|
Level: level,
|
|
}
|
|
block.Content = data[i:end]
|
|
p.addBlock(block)
|
|
}
|
|
return skip
|
|
}
|
|
|
|
func (p *Parser) isPrefixSpecialHeading(data []byte) bool {
|
|
if p.extensions|Mmark == 0 {
|
|
return false
|
|
}
|
|
if len(data) < 4 {
|
|
return false
|
|
}
|
|
if data[0] != '.' {
|
|
return false
|
|
}
|
|
if data[1] != '#' {
|
|
return false
|
|
}
|
|
if data[2] == '#' { // we don't support level, so nack this.
|
|
return false
|
|
}
|
|
|
|
if p.extensions&SpaceHeadings != 0 {
|
|
if data[2] != ' ' {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
func (p *Parser) prefixSpecialHeading(data []byte) int {
|
|
i := skipChar(data, 2, ' ') // ".#" skipped
|
|
end := skipUntilChar(data, i, '\n')
|
|
skip := end
|
|
id := ""
|
|
if p.extensions&HeadingIDs != 0 {
|
|
j, k := 0, 0
|
|
// find start/end of heading id
|
|
for j = i; j < end-1 && (data[j] != '{' || data[j+1] != '#'); j++ {
|
|
}
|
|
for k = j + 1; k < end && data[k] != '}'; k++ {
|
|
}
|
|
// extract heading id iff found
|
|
if j < end && k < end {
|
|
id = string(data[j+2 : k])
|
|
end = j
|
|
skip = k + 1
|
|
for end > 0 && data[end-1] == ' ' {
|
|
end--
|
|
}
|
|
}
|
|
}
|
|
for end > 0 && data[end-1] == '#' {
|
|
if isBackslashEscaped(data, end-1) {
|
|
break
|
|
}
|
|
end--
|
|
}
|
|
for end > 0 && data[end-1] == ' ' {
|
|
end--
|
|
}
|
|
if end > i {
|
|
if id == "" && p.extensions&AutoHeadingIDs != 0 {
|
|
id = sanitizeAnchorName(string(data[i:end]))
|
|
}
|
|
block := &ast.Heading{
|
|
HeadingID: id,
|
|
IsSpecial: true,
|
|
Level: 1, // always level 1.
|
|
}
|
|
block.Literal = data[i:end]
|
|
block.Content = data[i:end]
|
|
p.addBlock(block)
|
|
}
|
|
return skip
|
|
}
|
|
|
|
func (p *Parser) isUnderlinedHeading(data []byte) int {
|
|
// test of level 1 heading
|
|
if data[0] == '=' {
|
|
i := skipChar(data, 1, '=')
|
|
i = skipChar(data, i, ' ')
|
|
if i < len(data) && data[i] == '\n' {
|
|
return 1
|
|
}
|
|
return 0
|
|
}
|
|
|
|
// test of level 2 heading
|
|
if data[0] == '-' {
|
|
i := skipChar(data, 1, '-')
|
|
i = skipChar(data, i, ' ')
|
|
if i < len(data) && data[i] == '\n' {
|
|
return 2
|
|
}
|
|
return 0
|
|
}
|
|
|
|
return 0
|
|
}
|
|
|
|
func (p *Parser) titleBlock(data []byte, doRender bool) int {
|
|
if data[0] != '%' {
|
|
return 0
|
|
}
|
|
splitData := bytes.Split(data, []byte("\n"))
|
|
var i int
|
|
for idx, b := range splitData {
|
|
if !bytes.HasPrefix(b, []byte("%")) {
|
|
i = idx // - 1
|
|
break
|
|
}
|
|
}
|
|
|
|
data = bytes.Join(splitData[0:i], []byte("\n"))
|
|
consumed := len(data)
|
|
data = bytes.TrimPrefix(data, []byte("% "))
|
|
data = bytes.Replace(data, []byte("\n% "), []byte("\n"), -1)
|
|
block := &ast.Heading{
|
|
Level: 1,
|
|
IsTitleblock: true,
|
|
}
|
|
block.Content = data
|
|
p.addBlock(block)
|
|
|
|
return consumed
|
|
}
|
|
|
|
func (p *Parser) html(data []byte, doRender bool) int {
|
|
var i, j int
|
|
|
|
// identify the opening tag
|
|
if data[0] != '<' {
|
|
return 0
|
|
}
|
|
curtag, tagfound := p.htmlFindTag(data[1:])
|
|
|
|
// handle special cases
|
|
if !tagfound {
|
|
// check for an HTML comment
|
|
if size := p.htmlComment(data, doRender); size > 0 {
|
|
return size
|
|
}
|
|
|
|
// check for an <hr> tag
|
|
if size := p.htmlHr(data, doRender); size > 0 {
|
|
return size
|
|
}
|
|
|
|
// no special case recognized
|
|
return 0
|
|
}
|
|
|
|
// look for an unindented matching closing tag
|
|
// followed by a blank line
|
|
found := false
|
|
/*
|
|
closetag := []byte("\n</" + curtag + ">")
|
|
j = len(curtag) + 1
|
|
for !found {
|
|
// scan for a closing tag at the beginning of a line
|
|
if skip := bytes.Index(data[j:], closetag); skip >= 0 {
|
|
j += skip + len(closetag)
|
|
} else {
|
|
break
|
|
}
|
|
|
|
// see if it is the only thing on the line
|
|
if skip := p.isEmpty(data[j:]); skip > 0 {
|
|
// see if it is followed by a blank line/eof
|
|
j += skip
|
|
if j >= len(data) {
|
|
found = true
|
|
i = j
|
|
} else {
|
|
if skip := p.isEmpty(data[j:]); skip > 0 {
|
|
j += skip
|
|
found = true
|
|
i = j
|
|
}
|
|
}
|
|
}
|
|
}
|
|
*/
|
|
|
|
// if not found, try a second pass looking for indented match
|
|
// but not if tag is "ins" or "del" (following original Markdown.pl)
|
|
if !found && curtag != "ins" && curtag != "del" {
|
|
i = 1
|
|
for i < len(data) {
|
|
i++
|
|
for i < len(data) && !(data[i-1] == '<' && data[i] == '/') {
|
|
i++
|
|
}
|
|
|
|
if i+2+len(curtag) >= len(data) {
|
|
break
|
|
}
|
|
|
|
j = p.htmlFindEnd(curtag, data[i-1:])
|
|
|
|
if j > 0 {
|
|
i += j - 1
|
|
found = true
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
if !found {
|
|
return 0
|
|
}
|
|
|
|
// the end of the block has been found
|
|
if doRender {
|
|
// trim newlines
|
|
end := backChar(data, i, '\n')
|
|
htmlBLock := &ast.HTMLBlock{ast.Leaf{Content: data[:end]}}
|
|
p.addBlock(htmlBLock)
|
|
finalizeHTMLBlock(htmlBLock)
|
|
}
|
|
|
|
return i
|
|
}
|
|
|
|
func finalizeHTMLBlock(block *ast.HTMLBlock) {
|
|
block.Literal = block.Content
|
|
block.Content = nil
|
|
}
|
|
|
|
// HTML comment, lax form
|
|
func (p *Parser) htmlComment(data []byte, doRender bool) int {
|
|
i := p.inlineHTMLComment(data)
|
|
// needs to end with a blank line
|
|
if j := p.isEmpty(data[i:]); j > 0 {
|
|
size := i + j
|
|
if doRender {
|
|
// trim trailing newlines
|
|
end := backChar(data, size, '\n')
|
|
htmlBLock := &ast.HTMLBlock{ast.Leaf{Content: data[:end]}}
|
|
p.addBlock(htmlBLock)
|
|
finalizeHTMLBlock(htmlBLock)
|
|
}
|
|
return size
|
|
}
|
|
return 0
|
|
}
|
|
|
|
// HR, which is the only self-closing block tag considered
|
|
func (p *Parser) htmlHr(data []byte, doRender bool) int {
|
|
if len(data) < 4 {
|
|
return 0
|
|
}
|
|
if data[0] != '<' || (data[1] != 'h' && data[1] != 'H') || (data[2] != 'r' && data[2] != 'R') {
|
|
return 0
|
|
}
|
|
if data[3] != ' ' && data[3] != '/' && data[3] != '>' {
|
|
// not an <hr> tag after all; at least not a valid one
|
|
return 0
|
|
}
|
|
i := 3
|
|
for i < len(data) && data[i] != '>' && data[i] != '\n' {
|
|
i++
|
|
}
|
|
if i < len(data) && data[i] == '>' {
|
|
i++
|
|
if j := p.isEmpty(data[i:]); j > 0 {
|
|
size := i + j
|
|
if doRender {
|
|
// trim newlines
|
|
end := backChar(data, size, '\n')
|
|
htmlBlock := &ast.HTMLBlock{ast.Leaf{Content: data[:end]}}
|
|
p.addBlock(htmlBlock)
|
|
finalizeHTMLBlock(htmlBlock)
|
|
}
|
|
return size
|
|
}
|
|
}
|
|
return 0
|
|
}
|
|
|
|
func (p *Parser) htmlFindTag(data []byte) (string, bool) {
|
|
i := skipAlnum(data, 0)
|
|
key := string(data[:i])
|
|
if _, ok := blockTags[key]; ok {
|
|
return key, true
|
|
}
|
|
return "", false
|
|
}
|
|
|
|
func (p *Parser) htmlFindEnd(tag string, data []byte) int {
|
|
// assume data[0] == '<' && data[1] == '/' already tested
|
|
if tag == "hr" {
|
|
return 2
|
|
}
|
|
// check if tag is a match
|
|
closetag := []byte("</" + tag + ">")
|
|
if !bytes.HasPrefix(data, closetag) {
|
|
return 0
|
|
}
|
|
i := len(closetag)
|
|
|
|
// check that the rest of the line is blank
|
|
skip := 0
|
|
if skip = p.isEmpty(data[i:]); skip == 0 {
|
|
return 0
|
|
}
|
|
i += skip
|
|
skip = 0
|
|
|
|
if i >= len(data) {
|
|
return i
|
|
}
|
|
|
|
if p.extensions&LaxHTMLBlocks != 0 {
|
|
return i
|
|
}
|
|
if skip = p.isEmpty(data[i:]); skip == 0 {
|
|
// following line must be blank
|
|
return 0
|
|
}
|
|
|
|
return i + skip
|
|
}
|
|
|
|
func (*Parser) isEmpty(data []byte) int {
|
|
// it is okay to call isEmpty on an empty buffer
|
|
if len(data) == 0 {
|
|
return 0
|
|
}
|
|
|
|
var i int
|
|
for i = 0; i < len(data) && data[i] != '\n'; i++ {
|
|
if data[i] != ' ' && data[i] != '\t' {
|
|
return 0
|
|
}
|
|
}
|
|
i = skipCharN(data, i, '\n', 1)
|
|
return i
|
|
}
|
|
|
|
func (*Parser) isHRule(data []byte) bool {
|
|
i := 0
|
|
|
|
// skip up to three spaces
|
|
for i < 3 && data[i] == ' ' {
|
|
i++
|
|
}
|
|
|
|
// look at the hrule char
|
|
if data[i] != '*' && data[i] != '-' && data[i] != '_' {
|
|
return false
|
|
}
|
|
c := data[i]
|
|
|
|
// the whole line must be the char or whitespace
|
|
n := 0
|
|
for i < len(data) && data[i] != '\n' {
|
|
switch {
|
|
case data[i] == c:
|
|
n++
|
|
case data[i] != ' ':
|
|
return false
|
|
}
|
|
i++
|
|
}
|
|
|
|
return n >= 3
|
|
}
|
|
|
|
// isFenceLine checks if there's a fence line (e.g., ``` or ``` go) at the beginning of data,
|
|
// and returns the end index if so, or 0 otherwise. It also returns the marker found.
|
|
// If syntax is not nil, it gets set to the syntax specified in the fence line.
|
|
func isFenceLine(data []byte, syntax *string, oldmarker string) (end int, marker string) {
|
|
i, size := 0, 0
|
|
|
|
n := len(data)
|
|
// skip up to three spaces
|
|
for i < n && i < 3 && data[i] == ' ' {
|
|
i++
|
|
}
|
|
|
|
// check for the marker characters: ~ or `
|
|
if i >= n {
|
|
return 0, ""
|
|
}
|
|
if data[i] != '~' && data[i] != '`' {
|
|
return 0, ""
|
|
}
|
|
|
|
c := data[i]
|
|
|
|
// the whole line must be the same char or whitespace
|
|
for i < n && data[i] == c {
|
|
size++
|
|
i++
|
|
}
|
|
|
|
// the marker char must occur at least 3 times
|
|
if size < 3 {
|
|
return 0, ""
|
|
}
|
|
marker = string(data[i-size : i])
|
|
|
|
// if this is the end marker, it must match the beginning marker
|
|
if oldmarker != "" && marker != oldmarker {
|
|
return 0, ""
|
|
}
|
|
|
|
// TODO(shurcooL): It's probably a good idea to simplify the 2 code paths here
|
|
// into one, always get the syntax, and discard it if the caller doesn't care.
|
|
if syntax != nil {
|
|
syn := 0
|
|
i = skipChar(data, i, ' ')
|
|
|
|
if i >= n {
|
|
if i == n {
|
|
return i, marker
|
|
}
|
|
return 0, ""
|
|
}
|
|
|
|
syntaxStart := i
|
|
|
|
if data[i] == '{' {
|
|
i++
|
|
syntaxStart++
|
|
|
|
for i < n && data[i] != '}' && data[i] != '\n' {
|
|
syn++
|
|
i++
|
|
}
|
|
|
|
if i >= n || data[i] != '}' {
|
|
return 0, ""
|
|
}
|
|
|
|
// strip all whitespace at the beginning and the end
|
|
// of the {} block
|
|
for syn > 0 && isSpace(data[syntaxStart]) {
|
|
syntaxStart++
|
|
syn--
|
|
}
|
|
|
|
for syn > 0 && isSpace(data[syntaxStart+syn-1]) {
|
|
syn--
|
|
}
|
|
|
|
i++
|
|
} else {
|
|
for i < n && !isSpace(data[i]) {
|
|
syn++
|
|
i++
|
|
}
|
|
}
|
|
|
|
*syntax = string(data[syntaxStart : syntaxStart+syn])
|
|
}
|
|
|
|
i = skipChar(data, i, ' ')
|
|
if i >= n || data[i] != '\n' {
|
|
if i == n {
|
|
return i, marker
|
|
}
|
|
return 0, ""
|
|
}
|
|
return i + 1, marker // Take newline into account.
|
|
}
|
|
|
|
// fencedCodeBlock returns the end index if data contains a fenced code block at the beginning,
|
|
// or 0 otherwise. It writes to out if doRender is true, otherwise it has no side effects.
|
|
// If doRender is true, a final newline is mandatory to recognize the fenced code block.
|
|
func (p *Parser) fencedCodeBlock(data []byte, doRender bool) int {
|
|
var syntax string
|
|
beg, marker := isFenceLine(data, &syntax, "")
|
|
if beg == 0 || beg >= len(data) {
|
|
return 0
|
|
}
|
|
|
|
var work bytes.Buffer
|
|
work.WriteString(syntax)
|
|
work.WriteByte('\n')
|
|
|
|
for {
|
|
// safe to assume beg < len(data)
|
|
|
|
// check for the end of the code block
|
|
fenceEnd, _ := isFenceLine(data[beg:], nil, marker)
|
|
if fenceEnd != 0 {
|
|
beg += fenceEnd
|
|
break
|
|
}
|
|
|
|
// copy the current line
|
|
end := skipUntilChar(data, beg, '\n') + 1
|
|
|
|
// did we reach the end of the buffer without a closing marker?
|
|
if end >= len(data) {
|
|
return 0
|
|
}
|
|
|
|
// verbatim copy to the working buffer
|
|
if doRender {
|
|
work.Write(data[beg:end])
|
|
}
|
|
beg = end
|
|
}
|
|
|
|
if doRender {
|
|
codeBlock := &ast.CodeBlock{
|
|
IsFenced: true,
|
|
}
|
|
codeBlock.Content = work.Bytes() // TODO: get rid of temp buffer
|
|
|
|
if p.extensions&Mmark == 0 {
|
|
p.addBlock(codeBlock)
|
|
finalizeCodeBlock(codeBlock)
|
|
return beg
|
|
}
|
|
|
|
// Check for caption and if found make it a figure.
|
|
if captionContent, id, consumed := p.caption(data[beg:], []byte("Figure: ")); consumed > 0 {
|
|
figure := &ast.CaptionFigure{}
|
|
caption := &ast.Caption{}
|
|
figure.HeadingID = id
|
|
p.Inline(caption, captionContent)
|
|
|
|
p.addBlock(figure)
|
|
codeBlock.AsLeaf().Attribute = figure.AsContainer().Attribute
|
|
p.addChild(codeBlock)
|
|
finalizeCodeBlock(codeBlock)
|
|
p.addChild(caption)
|
|
p.finalize(figure)
|
|
|
|
beg += consumed
|
|
|
|
return beg
|
|
}
|
|
|
|
// Still here, normal block
|
|
p.addBlock(codeBlock)
|
|
finalizeCodeBlock(codeBlock)
|
|
}
|
|
|
|
return beg
|
|
}
|
|
|
|
func unescapeChar(str []byte) []byte {
|
|
if str[0] == '\\' {
|
|
return []byte{str[1]}
|
|
}
|
|
return []byte(html.UnescapeString(string(str)))
|
|
}
|
|
|
|
func unescapeString(str []byte) []byte {
|
|
if reBackslashOrAmp.Match(str) {
|
|
return reEntityOrEscapedChar.ReplaceAllFunc(str, unescapeChar)
|
|
}
|
|
return str
|
|
}
|
|
|
|
func finalizeCodeBlock(code *ast.CodeBlock) {
|
|
c := code.Content
|
|
if code.IsFenced {
|
|
newlinePos := bytes.IndexByte(c, '\n')
|
|
firstLine := c[:newlinePos]
|
|
rest := c[newlinePos+1:]
|
|
code.Info = unescapeString(bytes.Trim(firstLine, "\n"))
|
|
code.Literal = rest
|
|
} else {
|
|
code.Literal = c
|
|
}
|
|
code.Content = nil
|
|
}
|
|
|
|
func (p *Parser) table(data []byte) int {
|
|
i, columns, table := p.tableHeader(data)
|
|
if i == 0 {
|
|
return 0
|
|
}
|
|
|
|
p.addBlock(&ast.TableBody{})
|
|
|
|
for i < len(data) {
|
|
pipes, rowStart := 0, i
|
|
for ; i < len(data) && data[i] != '\n'; i++ {
|
|
if data[i] == '|' {
|
|
pipes++
|
|
}
|
|
}
|
|
|
|
if pipes == 0 {
|
|
i = rowStart
|
|
break
|
|
}
|
|
|
|
// include the newline in data sent to tableRow
|
|
i = skipCharN(data, i, '\n', 1)
|
|
|
|
if p.tableFooter(data[rowStart:i]) {
|
|
continue
|
|
}
|
|
|
|
p.tableRow(data[rowStart:i], columns, false)
|
|
}
|
|
if captionContent, id, consumed := p.caption(data[i:], []byte("Table: ")); consumed > 0 {
|
|
caption := &ast.Caption{}
|
|
p.Inline(caption, captionContent)
|
|
|
|
// Some switcheroo to re-insert the parsed table as a child of the captionfigure.
|
|
figure := &ast.CaptionFigure{}
|
|
figure.HeadingID = id
|
|
table2 := &ast.Table{}
|
|
// Retain any block level attributes.
|
|
table2.AsContainer().Attribute = table.AsContainer().Attribute
|
|
children := table.GetChildren()
|
|
ast.RemoveFromTree(table)
|
|
|
|
table2.SetChildren(children)
|
|
ast.AppendChild(figure, table2)
|
|
ast.AppendChild(figure, caption)
|
|
|
|
p.addChild(figure)
|
|
p.finalize(figure)
|
|
|
|
i += consumed
|
|
}
|
|
|
|
return i
|
|
}
|
|
|
|
// check if the specified position is preceded by an odd number of backslashes
|
|
func isBackslashEscaped(data []byte, i int) bool {
|
|
backslashes := 0
|
|
for i-backslashes-1 >= 0 && data[i-backslashes-1] == '\\' {
|
|
backslashes++
|
|
}
|
|
return backslashes&1 == 1
|
|
}
|
|
|
|
// tableHeaders parses the header. If recognized it will also add a table.
|
|
func (p *Parser) tableHeader(data []byte) (size int, columns []ast.CellAlignFlags, table ast.Node) {
|
|
i := 0
|
|
colCount := 1
|
|
for i = 0; i < len(data) && data[i] != '\n'; i++ {
|
|
if data[i] == '|' && !isBackslashEscaped(data, i) {
|
|
colCount++
|
|
}
|
|
}
|
|
|
|
// doesn't look like a table header
|
|
if colCount == 1 {
|
|
return
|
|
}
|
|
|
|
// include the newline in the data sent to tableRow
|
|
j := skipCharN(data, i, '\n', 1)
|
|
header := data[:j]
|
|
|
|
// column count ignores pipes at beginning or end of line
|
|
if data[0] == '|' {
|
|
colCount--
|
|
}
|
|
if i > 2 && data[i-1] == '|' && !isBackslashEscaped(data, i-1) {
|
|
colCount--
|
|
}
|
|
|
|
columns = make([]ast.CellAlignFlags, colCount)
|
|
|
|
// move on to the header underline
|
|
i++
|
|
if i >= len(data) {
|
|
return
|
|
}
|
|
|
|
if data[i] == '|' && !isBackslashEscaped(data, i) {
|
|
i++
|
|
}
|
|
i = skipChar(data, i, ' ')
|
|
|
|
// each column header is of form: / *:?-+:? *|/ with # dashes + # colons >= 3
|
|
// and trailing | optional on last column
|
|
col := 0
|
|
n := len(data)
|
|
for i < n && data[i] != '\n' {
|
|
dashes := 0
|
|
|
|
if data[i] == ':' {
|
|
i++
|
|
columns[col] |= ast.TableAlignmentLeft
|
|
dashes++
|
|
}
|
|
for i < n && data[i] == '-' {
|
|
i++
|
|
dashes++
|
|
}
|
|
if i < n && data[i] == ':' {
|
|
i++
|
|
columns[col] |= ast.TableAlignmentRight
|
|
dashes++
|
|
}
|
|
for i < n && data[i] == ' ' {
|
|
i++
|
|
}
|
|
if i == n {
|
|
return
|
|
}
|
|
// end of column test is messy
|
|
switch {
|
|
case dashes < 3:
|
|
// not a valid column
|
|
return
|
|
|
|
case data[i] == '|' && !isBackslashEscaped(data, i):
|
|
// marker found, now skip past trailing whitespace
|
|
col++
|
|
i++
|
|
for i < n && data[i] == ' ' {
|
|
i++
|
|
}
|
|
|
|
// trailing junk found after last column
|
|
if col >= colCount && i < len(data) && data[i] != '\n' {
|
|
return
|
|
}
|
|
|
|
case (data[i] != '|' || isBackslashEscaped(data, i)) && col+1 < colCount:
|
|
// something else found where marker was required
|
|
return
|
|
|
|
case data[i] == '\n':
|
|
// marker is optional for the last column
|
|
col++
|
|
|
|
default:
|
|
// trailing junk found after last column
|
|
return
|
|
}
|
|
}
|
|
if col != colCount {
|
|
return
|
|
}
|
|
|
|
table = &ast.Table{}
|
|
p.addBlock(table)
|
|
p.addBlock(&ast.TableHeader{})
|
|
p.tableRow(header, columns, true)
|
|
size = skipCharN(data, i, '\n', 1)
|
|
return
|
|
}
|
|
|
|
func (p *Parser) tableRow(data []byte, columns []ast.CellAlignFlags, header bool) {
|
|
p.addBlock(&ast.TableRow{})
|
|
i, col := 0, 0
|
|
|
|
if data[i] == '|' && !isBackslashEscaped(data, i) {
|
|
i++
|
|
}
|
|
|
|
n := len(data)
|
|
for col = 0; col < len(columns) && i < n; col++ {
|
|
for i < n && data[i] == ' ' {
|
|
i++
|
|
}
|
|
|
|
cellStart := i
|
|
|
|
for i < n && (data[i] != '|' || isBackslashEscaped(data, i)) && data[i] != '\n' {
|
|
i++
|
|
}
|
|
|
|
cellEnd := i
|
|
|
|
// skip the end-of-cell marker, possibly taking us past end of buffer
|
|
i++
|
|
|
|
for cellEnd > cellStart && cellEnd-1 < n && data[cellEnd-1] == ' ' {
|
|
cellEnd--
|
|
}
|
|
|
|
block := &ast.TableCell{
|
|
IsHeader: header,
|
|
Align: columns[col],
|
|
}
|
|
block.Content = data[cellStart:cellEnd]
|
|
p.addBlock(block)
|
|
}
|
|
|
|
// pad it out with empty columns to get the right number
|
|
for ; col < len(columns); col++ {
|
|
block := &ast.TableCell{
|
|
IsHeader: header,
|
|
Align: columns[col],
|
|
}
|
|
p.addBlock(block)
|
|
}
|
|
|
|
// silently ignore rows with too many cells
|
|
}
|
|
|
|
// tableFooter parses the (optional) table footer.
|
|
func (p *Parser) tableFooter(data []byte) bool {
|
|
colCount := 1
|
|
for i := 0; i < len(data) && data[i] != '\n'; i++ {
|
|
if data[i] == '|' && !isBackslashEscaped(data, i) {
|
|
colCount++
|
|
continue
|
|
}
|
|
// remaining data must be the = character
|
|
if data[i] != '=' {
|
|
return false
|
|
}
|
|
}
|
|
|
|
// doesn't look like a table footer
|
|
if colCount == 1 {
|
|
return false
|
|
}
|
|
|
|
p.addBlock(&ast.TableFooter{})
|
|
|
|
return true
|
|
}
|
|
|
|
// returns blockquote prefix length
|
|
func (p *Parser) quotePrefix(data []byte) int {
|
|
i := 0
|
|
n := len(data)
|
|
for i < 3 && i < n && data[i] == ' ' {
|
|
i++
|
|
}
|
|
if i < n && data[i] == '>' {
|
|
if i+1 < n && data[i+1] == ' ' {
|
|
return i + 2
|
|
}
|
|
return i + 1
|
|
}
|
|
return 0
|
|
}
|
|
|
|
// blockquote ends with at least one blank line
|
|
// followed by something without a blockquote prefix
|
|
func (p *Parser) terminateBlockquote(data []byte, beg, end int) bool {
|
|
if p.isEmpty(data[beg:]) <= 0 {
|
|
return false
|
|
}
|
|
if end >= len(data) {
|
|
return true
|
|
}
|
|
return p.quotePrefix(data[end:]) == 0 && p.isEmpty(data[end:]) == 0
|
|
}
|
|
|
|
// parse a blockquote fragment
|
|
func (p *Parser) quote(data []byte) int {
|
|
var raw bytes.Buffer
|
|
beg, end := 0, 0
|
|
for beg < len(data) {
|
|
end = beg
|
|
// Step over whole lines, collecting them. While doing that, check for
|
|
// fenced code and if one's found, incorporate it altogether,
|
|
// irregardless of any contents inside it
|
|
for end < len(data) && data[end] != '\n' {
|
|
if p.extensions&FencedCode != 0 {
|
|
if i := p.fencedCodeBlock(data[end:], false); i > 0 {
|
|
// -1 to compensate for the extra end++ after the loop:
|
|
end += i - 1
|
|
break
|
|
}
|
|
}
|
|
end++
|
|
}
|
|
end = skipCharN(data, end, '\n', 1)
|
|
if pre := p.quotePrefix(data[beg:]); pre > 0 {
|
|
// skip the prefix
|
|
beg += pre
|
|
} else if p.terminateBlockquote(data, beg, end) {
|
|
break
|
|
}
|
|
// this line is part of the blockquote
|
|
raw.Write(data[beg:end])
|
|
beg = end
|
|
}
|
|
|
|
if p.extensions&Mmark == 0 {
|
|
block := p.addBlock(&ast.BlockQuote{})
|
|
p.block(raw.Bytes())
|
|
p.finalize(block)
|
|
return end
|
|
}
|
|
|
|
if captionContent, id, consumed := p.caption(data[end:], []byte("Quote: ")); consumed > 0 {
|
|
figure := &ast.CaptionFigure{}
|
|
caption := &ast.Caption{}
|
|
figure.HeadingID = id
|
|
p.Inline(caption, captionContent)
|
|
|
|
p.addBlock(figure) // this discard any attributes
|
|
block := &ast.BlockQuote{}
|
|
block.AsContainer().Attribute = figure.AsContainer().Attribute
|
|
p.addChild(block)
|
|
p.block(raw.Bytes())
|
|
p.finalize(block)
|
|
|
|
p.addChild(caption)
|
|
p.finalize(figure)
|
|
|
|
end += consumed
|
|
|
|
return end
|
|
}
|
|
|
|
block := p.addBlock(&ast.BlockQuote{})
|
|
p.block(raw.Bytes())
|
|
p.finalize(block)
|
|
|
|
return end
|
|
}
|
|
|
|
// returns prefix length for block code
|
|
func (p *Parser) codePrefix(data []byte) int {
|
|
n := len(data)
|
|
if n >= 1 && data[0] == '\t' {
|
|
return 1
|
|
}
|
|
if n >= 4 && data[3] == ' ' && data[2] == ' ' && data[1] == ' ' && data[0] == ' ' {
|
|
return 4
|
|
}
|
|
return 0
|
|
}
|
|
|
|
func (p *Parser) code(data []byte) int {
|
|
var work bytes.Buffer
|
|
|
|
i := 0
|
|
for i < len(data) {
|
|
beg := i
|
|
|
|
i = skipUntilChar(data, i, '\n')
|
|
i = skipCharN(data, i, '\n', 1)
|
|
|
|
blankline := p.isEmpty(data[beg:i]) > 0
|
|
if pre := p.codePrefix(data[beg:i]); pre > 0 {
|
|
beg += pre
|
|
} else if !blankline {
|
|
// non-empty, non-prefixed line breaks the pre
|
|
i = beg
|
|
break
|
|
}
|
|
|
|
// verbatim copy to the working buffer
|
|
if blankline {
|
|
work.WriteByte('\n')
|
|
} else {
|
|
work.Write(data[beg:i])
|
|
}
|
|
}
|
|
|
|
// trim all the \n off the end of work
|
|
workbytes := work.Bytes()
|
|
|
|
eol := backChar(workbytes, len(workbytes), '\n')
|
|
|
|
if eol != len(workbytes) {
|
|
work.Truncate(eol)
|
|
}
|
|
|
|
work.WriteByte('\n')
|
|
|
|
codeBlock := &ast.CodeBlock{
|
|
IsFenced: false,
|
|
}
|
|
// TODO: get rid of temp buffer
|
|
codeBlock.Content = work.Bytes()
|
|
p.addBlock(codeBlock)
|
|
finalizeCodeBlock(codeBlock)
|
|
|
|
return i
|
|
}
|
|
|
|
// returns unordered list item prefix
|
|
func (p *Parser) uliPrefix(data []byte) int {
|
|
// start with up to 3 spaces
|
|
i := skipCharN(data, 0, ' ', 3)
|
|
|
|
if i >= len(data)-1 {
|
|
return 0
|
|
}
|
|
// need one of {'*', '+', '-'} followed by a space or a tab
|
|
if (data[i] != '*' && data[i] != '+' && data[i] != '-') ||
|
|
(data[i+1] != ' ' && data[i+1] != '\t') {
|
|
return 0
|
|
}
|
|
return i + 2
|
|
}
|
|
|
|
// returns ordered list item prefix
|
|
func (p *Parser) oliPrefix(data []byte) int {
|
|
// start with up to 3 spaces
|
|
i := skipCharN(data, 0, ' ', 3)
|
|
|
|
// count the digits
|
|
start := i
|
|
for i < len(data) && data[i] >= '0' && data[i] <= '9' {
|
|
i++
|
|
}
|
|
if start == i || i >= len(data)-1 {
|
|
return 0
|
|
}
|
|
|
|
// we need >= 1 digits followed by a dot and a space or a tab
|
|
if data[i] != '.' || !(data[i+1] == ' ' || data[i+1] == '\t') {
|
|
return 0
|
|
}
|
|
return i + 2
|
|
}
|
|
|
|
// returns definition list item prefix
|
|
func (p *Parser) dliPrefix(data []byte) int {
|
|
if len(data) < 2 {
|
|
return 0
|
|
}
|
|
// need a ':' followed by a space or a tab
|
|
if data[0] != ':' || !(data[1] == ' ' || data[1] == '\t') {
|
|
return 0
|
|
}
|
|
i := skipChar(data, 0, ' ')
|
|
return i + 2
|
|
}
|
|
|
|
// parse ordered or unordered list block
|
|
func (p *Parser) list(data []byte, flags ast.ListType, start int) int {
|
|
i := 0
|
|
flags |= ast.ListItemBeginningOfList
|
|
list := &ast.List{
|
|
ListFlags: flags,
|
|
Tight: true,
|
|
Start: start,
|
|
}
|
|
block := p.addBlock(list)
|
|
|
|
for i < len(data) {
|
|
skip := p.listItem(data[i:], &flags)
|
|
if flags&ast.ListItemContainsBlock != 0 {
|
|
list.Tight = false
|
|
}
|
|
i += skip
|
|
if skip == 0 || flags&ast.ListItemEndOfList != 0 {
|
|
break
|
|
}
|
|
flags &= ^ast.ListItemBeginningOfList
|
|
}
|
|
|
|
above := block.GetParent()
|
|
finalizeList(list)
|
|
p.tip = above
|
|
return i
|
|
}
|
|
|
|
// Returns true if the list item is not the same type as its parent list
|
|
func (p *Parser) listTypeChanged(data []byte, flags *ast.ListType) bool {
|
|
if p.dliPrefix(data) > 0 && *flags&ast.ListTypeDefinition == 0 {
|
|
return true
|
|
} else if p.oliPrefix(data) > 0 && *flags&ast.ListTypeOrdered == 0 {
|
|
return true
|
|
} else if p.uliPrefix(data) > 0 && (*flags&ast.ListTypeOrdered != 0 || *flags&ast.ListTypeDefinition != 0) {
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// Returns true if block ends with a blank line, descending if needed
|
|
// into lists and sublists.
|
|
func endsWithBlankLine(block ast.Node) bool {
|
|
// TODO: figure this out. Always false now.
|
|
for block != nil {
|
|
//if block.lastLineBlank {
|
|
//return true
|
|
//}
|
|
switch block.(type) {
|
|
case *ast.List, *ast.ListItem:
|
|
block = ast.GetLastChild(block)
|
|
default:
|
|
return false
|
|
}
|
|
}
|
|
return false
|
|
}
|
|
|
|
func finalizeList(list *ast.List) {
|
|
items := list.Parent.GetChildren()
|
|
lastItemIdx := len(items) - 1
|
|
for i, item := range items {
|
|
isLastItem := i == lastItemIdx
|
|
// check for non-final list item ending with blank line:
|
|
if !isLastItem && endsWithBlankLine(item) {
|
|
list.Tight = false
|
|
break
|
|
}
|
|
// recurse into children of list item, to see if there are spaces
|
|
// between any of them:
|
|
subItems := item.GetParent().GetChildren()
|
|
lastSubItemIdx := len(subItems) - 1
|
|
for j, subItem := range subItems {
|
|
isLastSubItem := j == lastSubItemIdx
|
|
if (!isLastItem || !isLastSubItem) && endsWithBlankLine(subItem) {
|
|
list.Tight = false
|
|
break
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Parse a single list item.
|
|
// Assumes initial prefix is already removed if this is a sublist.
|
|
func (p *Parser) listItem(data []byte, flags *ast.ListType) int {
|
|
// keep track of the indentation of the first line
|
|
itemIndent := 0
|
|
if data[0] == '\t' {
|
|
itemIndent += 4
|
|
} else {
|
|
for itemIndent < 3 && data[itemIndent] == ' ' {
|
|
itemIndent++
|
|
}
|
|
}
|
|
|
|
var bulletChar byte = '*'
|
|
i := p.uliPrefix(data)
|
|
if i == 0 {
|
|
i = p.oliPrefix(data)
|
|
} else {
|
|
bulletChar = data[i-2]
|
|
}
|
|
if i == 0 {
|
|
i = p.dliPrefix(data)
|
|
// reset definition term flag
|
|
if i > 0 {
|
|
*flags &= ^ast.ListTypeTerm
|
|
}
|
|
}
|
|
if i == 0 {
|
|
// if in definition list, set term flag and continue
|
|
if *flags&ast.ListTypeDefinition != 0 {
|
|
*flags |= ast.ListTypeTerm
|
|
} else {
|
|
return 0
|
|
}
|
|
}
|
|
|
|
// skip leading whitespace on first line
|
|
i = skipChar(data, i, ' ')
|
|
|
|
// find the end of the line
|
|
line := i
|
|
for i > 0 && i < len(data) && data[i-1] != '\n' {
|
|
i++
|
|
}
|
|
|
|
// get working buffer
|
|
var raw bytes.Buffer
|
|
|
|
// put the first line into the working buffer
|
|
raw.Write(data[line:i])
|
|
line = i
|
|
|
|
// process the following lines
|
|
containsBlankLine := false
|
|
sublist := 0
|
|
|
|
gatherlines:
|
|
for line < len(data) {
|
|
i++
|
|
|
|
// find the end of this line
|
|
for i < len(data) && data[i-1] != '\n' {
|
|
i++
|
|
}
|
|
|
|
// if it is an empty line, guess that it is part of this item
|
|
// and move on to the next line
|
|
if p.isEmpty(data[line:i]) > 0 {
|
|
containsBlankLine = true
|
|
line = i
|
|
continue
|
|
}
|
|
|
|
// calculate the indentation
|
|
indent := 0
|
|
indentIndex := 0
|
|
if data[line] == '\t' {
|
|
indentIndex++
|
|
indent += 4
|
|
} else {
|
|
for indent < 4 && line+indent < i && data[line+indent] == ' ' {
|
|
indent++
|
|
indentIndex++
|
|
}
|
|
}
|
|
|
|
chunk := data[line+indentIndex : i]
|
|
|
|
// evaluate how this line fits in
|
|
switch {
|
|
// is this a nested list item?
|
|
case (p.uliPrefix(chunk) > 0 && !p.isHRule(chunk)) || p.oliPrefix(chunk) > 0 || p.dliPrefix(chunk) > 0:
|
|
|
|
// to be a nested list, it must be indented more
|
|
// if not, it is either a different kind of list
|
|
// or the next item in the same list
|
|
if indent <= itemIndent {
|
|
if p.listTypeChanged(chunk, flags) {
|
|
*flags |= ast.ListItemEndOfList
|
|
} else if containsBlankLine {
|
|
*flags |= ast.ListItemContainsBlock
|
|
}
|
|
|
|
break gatherlines
|
|
}
|
|
|
|
if containsBlankLine {
|
|
*flags |= ast.ListItemContainsBlock
|
|
}
|
|
|
|
// is this the first item in the nested list?
|
|
if sublist == 0 {
|
|
sublist = raw.Len()
|
|
// in the case of dliPrefix we are too late and need to search back for the definition item, which
|
|
// should be on the previous line, we then adjust sublist to start there.
|
|
if p.dliPrefix(chunk) > 0 {
|
|
sublist = backUntilChar(raw.Bytes(), raw.Len()-1, '\n')
|
|
}
|
|
}
|
|
|
|
// is this a nested prefix heading?
|
|
case p.isPrefixHeading(chunk), p.isPrefixSpecialHeading(chunk):
|
|
// if the heading is not indented, it is not nested in the list
|
|
// and thus ends the list
|
|
if containsBlankLine && indent < 4 {
|
|
*flags |= ast.ListItemEndOfList
|
|
break gatherlines
|
|
}
|
|
*flags |= ast.ListItemContainsBlock
|
|
|
|
// anything following an empty line is only part
|
|
// of this item if it is indented 4 spaces
|
|
// (regardless of the indentation of the beginning of the item)
|
|
case containsBlankLine && indent < 4:
|
|
if *flags&ast.ListTypeDefinition != 0 && i < len(data)-1 {
|
|
// is the next item still a part of this list?
|
|
next := i
|
|
for next < len(data) && data[next] != '\n' {
|
|
next++
|
|
}
|
|
for next < len(data)-1 && data[next] == '\n' {
|
|
next++
|
|
}
|
|
if i < len(data)-1 && data[i] != ':' && next < len(data)-1 && data[next] != ':' {
|
|
*flags |= ast.ListItemEndOfList
|
|
}
|
|
} else {
|
|
*flags |= ast.ListItemEndOfList
|
|
}
|
|
break gatherlines
|
|
|
|
// a blank line means this should be parsed as a block
|
|
case containsBlankLine:
|
|
raw.WriteByte('\n')
|
|
*flags |= ast.ListItemContainsBlock
|
|
}
|
|
|
|
// if this line was preceded by one or more blanks,
|
|
// re-introduce the blank into the buffer
|
|
if containsBlankLine {
|
|
containsBlankLine = false
|
|
raw.WriteByte('\n')
|
|
}
|
|
|
|
// add the line into the working buffer without prefix
|
|
raw.Write(data[line+indentIndex : i])
|
|
|
|
line = i
|
|
}
|
|
|
|
rawBytes := raw.Bytes()
|
|
|
|
listItem := &ast.ListItem{
|
|
ListFlags: *flags,
|
|
Tight: false,
|
|
BulletChar: bulletChar,
|
|
Delimiter: '.', // Only '.' is possible in Markdown, but ')' will also be possible in CommonMark
|
|
}
|
|
p.addBlock(listItem)
|
|
|
|
// render the contents of the list item
|
|
if *flags&ast.ListItemContainsBlock != 0 && *flags&ast.ListTypeTerm == 0 {
|
|
// intermediate render of block item, except for definition term
|
|
if sublist > 0 {
|
|
p.block(rawBytes[:sublist])
|
|
p.block(rawBytes[sublist:])
|
|
} else {
|
|
p.block(rawBytes)
|
|
}
|
|
} else {
|
|
// intermediate render of inline item
|
|
para := &ast.Paragraph{}
|
|
if sublist > 0 {
|
|
para.Content = rawBytes[:sublist]
|
|
} else {
|
|
para.Content = rawBytes
|
|
}
|
|
p.addChild(para)
|
|
if sublist > 0 {
|
|
p.block(rawBytes[sublist:])
|
|
}
|
|
}
|
|
return line
|
|
}
|
|
|
|
// render a single paragraph that has already been parsed out
|
|
func (p *Parser) renderParagraph(data []byte) {
|
|
if len(data) == 0 {
|
|
return
|
|
}
|
|
|
|
// trim leading spaces
|
|
beg := skipChar(data, 0, ' ')
|
|
|
|
end := len(data)
|
|
// trim trailing newline
|
|
if data[len(data)-1] == '\n' {
|
|
end--
|
|
}
|
|
|
|
// trim trailing spaces
|
|
for end > beg && data[end-1] == ' ' {
|
|
end--
|
|
}
|
|
para := &ast.Paragraph{}
|
|
para.Content = data[beg:end]
|
|
p.addBlock(para)
|
|
}
|
|
|
|
// blockMath handle block surround with $$
|
|
func (p *Parser) blockMath(data []byte) int {
|
|
if len(data) <= 4 || data[0] != '$' || data[1] != '$' || data[2] == '$' {
|
|
return 0
|
|
}
|
|
|
|
// find next $$
|
|
var end int
|
|
for end = 2; end+1 < len(data) && (data[end] != '$' || data[end+1] != '$'); end++ {
|
|
}
|
|
|
|
// $$ not match
|
|
if end+1 == len(data) {
|
|
return 0
|
|
}
|
|
|
|
// render the display math
|
|
mathBlock := &ast.MathBlock{}
|
|
mathBlock.Literal = data[2:end]
|
|
p.addBlock(mathBlock)
|
|
|
|
return end + 2
|
|
}
|
|
|
|
func (p *Parser) paragraph(data []byte) int {
|
|
// prev: index of 1st char of previous line
|
|
// line: index of 1st char of current line
|
|
// i: index of cursor/end of current line
|
|
var prev, line, i int
|
|
tabSize := tabSizeDefault
|
|
if p.extensions&TabSizeEight != 0 {
|
|
tabSize = tabSizeDouble
|
|
}
|
|
// keep going until we find something to mark the end of the paragraph
|
|
for i < len(data) {
|
|
// mark the beginning of the current line
|
|
prev = line
|
|
current := data[i:]
|
|
line = i
|
|
|
|
// did we find a reference or a footnote? If so, end a paragraph
|
|
// preceding it and report that we have consumed up to the end of that
|
|
// reference:
|
|
if refEnd := isReference(p, current, tabSize); refEnd > 0 {
|
|
p.renderParagraph(data[:i])
|
|
return i + refEnd
|
|
}
|
|
|
|
// did we find a blank line marking the end of the paragraph?
|
|
if n := p.isEmpty(current); n > 0 {
|
|
// did this blank line followed by a definition list item?
|
|
if p.extensions&DefinitionLists != 0 {
|
|
if i < len(data)-1 && data[i+1] == ':' {
|
|
listLen := p.list(data[prev:], ast.ListTypeDefinition, 0)
|
|
return prev + listLen
|
|
}
|
|
}
|
|
|
|
p.renderParagraph(data[:i])
|
|
return i + n
|
|
}
|
|
|
|
// an underline under some text marks a heading, so our paragraph ended on prev line
|
|
if i > 0 {
|
|
if level := p.isUnderlinedHeading(current); level > 0 {
|
|
// render the paragraph
|
|
p.renderParagraph(data[:prev])
|
|
|
|
// ignore leading and trailing whitespace
|
|
eol := i - 1
|
|
for prev < eol && data[prev] == ' ' {
|
|
prev++
|
|
}
|
|
for eol > prev && data[eol-1] == ' ' {
|
|
eol--
|
|
}
|
|
|
|
id := ""
|
|
if p.extensions&AutoHeadingIDs != 0 {
|
|
id = sanitizeAnchorName(string(data[prev:eol]))
|
|
}
|
|
|
|
block := &ast.Heading{
|
|
Level: level,
|
|
HeadingID: id,
|
|
}
|
|
block.Content = data[prev:eol]
|
|
p.addBlock(block)
|
|
|
|
// find the end of the underline
|
|
return skipUntilChar(data, i, '\n')
|
|
}
|
|
}
|
|
|
|
// if the next line starts a block of HTML, then the paragraph ends here
|
|
if p.extensions&LaxHTMLBlocks != 0 {
|
|
if data[i] == '<' && p.html(current, false) > 0 {
|
|
// rewind to before the HTML block
|
|
p.renderParagraph(data[:i])
|
|
return i
|
|
}
|
|
}
|
|
|
|
// if there's a prefixed heading or a horizontal rule after this, paragraph is over
|
|
if p.isPrefixHeading(current) || p.isPrefixSpecialHeading(current) || p.isHRule(current) {
|
|
p.renderParagraph(data[:i])
|
|
return i
|
|
}
|
|
|
|
// if there's a fenced code block, paragraph is over
|
|
if p.extensions&FencedCode != 0 {
|
|
if p.fencedCodeBlock(current, false) > 0 {
|
|
p.renderParagraph(data[:i])
|
|
return i
|
|
}
|
|
}
|
|
|
|
// if there's a figure block, paragraph is over
|
|
if p.extensions&Mmark != 0 {
|
|
if p.figureBlock(current, false) > 0 {
|
|
p.renderParagraph(data[:i])
|
|
return i
|
|
}
|
|
}
|
|
|
|
// if there's a definition list item, prev line is a definition term
|
|
if p.extensions&DefinitionLists != 0 {
|
|
if p.dliPrefix(current) != 0 {
|
|
ret := p.list(data[prev:], ast.ListTypeDefinition, 0)
|
|
return ret + prev
|
|
}
|
|
}
|
|
|
|
// if there's a list after this, paragraph is over
|
|
if p.extensions&NoEmptyLineBeforeBlock != 0 {
|
|
if p.uliPrefix(current) != 0 ||
|
|
p.oliPrefix(current) != 0 ||
|
|
p.quotePrefix(current) != 0 ||
|
|
p.codePrefix(current) != 0 {
|
|
p.renderParagraph(data[:i])
|
|
return i
|
|
}
|
|
}
|
|
|
|
// otherwise, scan to the beginning of the next line
|
|
nl := bytes.IndexByte(data[i:], '\n')
|
|
if nl >= 0 {
|
|
i += nl + 1
|
|
} else {
|
|
i += len(data[i:])
|
|
}
|
|
}
|
|
|
|
p.renderParagraph(data[:i])
|
|
return i
|
|
}
|
|
|
|
// skipChar advances i as long as data[i] == c
|
|
func skipChar(data []byte, i int, c byte) int {
|
|
n := len(data)
|
|
for i < n && data[i] == c {
|
|
i++
|
|
}
|
|
return i
|
|
}
|
|
|
|
// like skipChar but only skips up to max characters
|
|
func skipCharN(data []byte, i int, c byte, max int) int {
|
|
n := len(data)
|
|
for i < n && max > 0 && data[i] == c {
|
|
i++
|
|
max--
|
|
}
|
|
return i
|
|
}
|
|
|
|
// skipUntilChar advances i as long as data[i] != c
|
|
func skipUntilChar(data []byte, i int, c byte) int {
|
|
n := len(data)
|
|
for i < n && data[i] != c {
|
|
i++
|
|
}
|
|
return i
|
|
}
|
|
|
|
func skipAlnum(data []byte, i int) int {
|
|
n := len(data)
|
|
for i < n && isAlnum(data[i]) {
|
|
i++
|
|
}
|
|
return i
|
|
}
|
|
|
|
func skipSpace(data []byte, i int) int {
|
|
n := len(data)
|
|
for i < n && isSpace(data[i]) {
|
|
i++
|
|
}
|
|
return i
|
|
}
|
|
|
|
func backChar(data []byte, i int, c byte) int {
|
|
for i > 0 && data[i-1] == c {
|
|
i--
|
|
}
|
|
return i
|
|
}
|
|
|
|
func backUntilChar(data []byte, i int, c byte) int {
|
|
for i > 0 && data[i-1] != c {
|
|
i--
|
|
}
|
|
return i
|
|
}
|