From 64fa922ec013079f8f0c90fc9e93c56db3611d30 Mon Sep 17 00:00:00 2001 From: Tulir Asokan Date: Sun, 22 Apr 2018 21:25:06 +0300 Subject: Switch to dep --- vendor/gopkg.in/russross/blackfriday.v2/block.go | 1549 ++++++++++++++++++++++ 1 file changed, 1549 insertions(+) create mode 100644 vendor/gopkg.in/russross/blackfriday.v2/block.go (limited to 'vendor/gopkg.in/russross/blackfriday.v2/block.go') diff --git a/vendor/gopkg.in/russross/blackfriday.v2/block.go b/vendor/gopkg.in/russross/blackfriday.v2/block.go new file mode 100644 index 0000000..d7da33f --- /dev/null +++ b/vendor/gopkg.in/russross/blackfriday.v2/block.go @@ -0,0 +1,1549 @@ +// +// Blackfriday Markdown Processor +// Available at http://github.com/russross/blackfriday +// +// Copyright © 2011 Russ Ross . +// Distributed under the Simplified BSD License. +// See README.md for details. +// + +// +// Functions to parse block-level elements. +// + +package blackfriday + +import ( + "bytes" + "html" + "regexp" + + "github.com/shurcooL/sanitized_anchor_name" +) + +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) +) + +// Parse block-level data. +// Note: this function and many that it calls assume that +// the input buffer ends with a newline. +func (p *Markdown) 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 { + // prefixed heading: + // + // # Heading 1 + // ## Heading 2 + // ... + // ###### Heading 6 + if p.isPrefixHeading(data) { + data = data[p.prefixHeading(data):] + continue + } + + // block of preformatted HTML: + // + //
+ // ... + //
+ 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) { + p.addBlock(HorizontalRule, nil) + var i int + for i = 0; i < len(data) && data[i] != '\n'; i++ { + } + 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 + } + + // 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):] + continue + } + + // a numbered/ordered list: + // + // 1. Item 1 + // 2. Item 2 + if p.oliPrefix(data) > 0 { + data = data[p.list(data, ListTypeOrdered):] + 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, ListTypeDefinition):] + continue + } + } + + // anything else must look like a normal paragraph + // note: this finds underlined headings, too + data = data[p.paragraph(data):] + } + + p.nesting-- +} + +func (p *Markdown) addBlock(typ NodeType, content []byte) *Node { + p.closeUnmatchedBlocks() + container := p.addChild(typ, 0) + container.content = content + return container +} + +func (p *Markdown) isPrefixHeading(data []byte) bool { + if data[0] != '#' { + return false + } + + if p.extensions&SpaceHeadings != 0 { + level := 0 + for level < 6 && level < len(data) && data[level] == '#' { + level++ + } + if level == len(data) || data[level] != ' ' { + return false + } + } + return true +} + +func (p *Markdown) prefixHeading(data []byte) int { + level := 0 + for level < 6 && level < len(data) && data[level] == '#' { + level++ + } + 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 = sanitized_anchor_name.Create(string(data[i:end])) + } + block := p.addBlock(Heading, data[i:end]) + block.HeadingID = id + block.Level = level + } + return skip +} + +func (p *Markdown) 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 *Markdown) 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 := p.addBlock(Heading, data) + block.Level = 1 + block.IsTitleblock = true + + return consumed +} + +func (p *Markdown) 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
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") + 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 := i + for end > 0 && data[end-1] == '\n' { + end-- + } + finalizeHTMLBlock(p.addBlock(HTMLBlock, data[:end])) + } + + return i +} + +func finalizeHTMLBlock(block *Node) { + block.Literal = block.content + block.content = nil +} + +// HTML comment, lax form +func (p *Markdown) 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 := size + for end > 0 && data[end-1] == '\n' { + end-- + } + block := p.addBlock(HTMLBlock, data[:end]) + finalizeHTMLBlock(block) + } + return size + } + return 0 +} + +// HR, which is the only self-closing block tag considered +func (p *Markdown) 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
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 := size + for end > 0 && data[end-1] == '\n' { + end-- + } + finalizeHTMLBlock(p.addBlock(HTMLBlock, data[:end])) + } + return size + } + } + return 0 +} + +func (p *Markdown) htmlFindTag(data []byte) (string, bool) { + i := 0 + for i < len(data) && isalnum(data[i]) { + i++ + } + key := string(data[:i]) + if _, ok := blockTags[key]; ok { + return key, true + } + return "", false +} + +func (p *Markdown) 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("") + 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 (*Markdown) 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 + } + } + if i < len(data) && data[i] == '\n' { + i++ + } + return i +} + +func (*Markdown) 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 + + // skip up to three spaces + for i < len(data) && i < 3 && data[i] == ' ' { + i++ + } + + // check for the marker characters: ~ or ` + if i >= len(data) { + return 0, "" + } + if data[i] != '~' && data[i] != '`' { + return 0, "" + } + + c := data[i] + + // the whole line must be the same char or whitespace + for i < len(data) && 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 >= len(data) { + if i == len(data) { + return i, marker + } + return 0, "" + } + + syntaxStart := i + + if data[i] == '{' { + i++ + syntaxStart++ + + for i < len(data) && data[i] != '}' && data[i] != '\n' { + syn++ + i++ + } + + if i >= len(data) || 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 < len(data) && !isspace(data[i]) { + syn++ + i++ + } + } + + *syntax = string(data[syntaxStart : syntaxStart+syn]) + } + + i = skipChar(data, i, ' ') + if i >= len(data) || data[i] != '\n' { + if i == len(data) { + 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 *Markdown) 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.Write([]byte(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 { + block := p.addBlock(CodeBlock, work.Bytes()) // TODO: get rid of temp buffer + block.IsFenced = true + finalizeCodeBlock(block) + } + + 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(block *Node) { + if block.IsFenced { + newlinePos := bytes.IndexByte(block.content, '\n') + firstLine := block.content[:newlinePos] + rest := block.content[newlinePos+1:] + block.Info = unescapeString(bytes.Trim(firstLine, "\n")) + block.Literal = rest + } else { + block.Literal = block.content + } + block.content = nil +} + +func (p *Markdown) table(data []byte) int { + table := p.addBlock(Table, nil) + i, columns := p.tableHeader(data) + if i == 0 { + p.tip = table.Parent + table.Unlink() + return 0 + } + + p.addBlock(TableBody, nil) + + 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 + if i < len(data) && data[i] == '\n' { + i++ + } + p.tableRow(data[rowStart:i], columns, false) + } + + 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 +} + +func (p *Markdown) tableHeader(data []byte) (size int, columns []CellAlignFlags) { + 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 := i + if j < len(data) && data[j] == '\n' { + j++ + } + 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([]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 + for i < len(data) && data[i] != '\n' { + dashes := 0 + + if data[i] == ':' { + i++ + columns[col] |= TableAlignmentLeft + dashes++ + } + for i < len(data) && data[i] == '-' { + i++ + dashes++ + } + if i < len(data) && data[i] == ':' { + i++ + columns[col] |= TableAlignmentRight + dashes++ + } + for i < len(data) && data[i] == ' ' { + i++ + } + if i == len(data) { + 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 < len(data) && 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 + } + + p.addBlock(TableHead, nil) + p.tableRow(header, columns, true) + size = i + if size < len(data) && data[size] == '\n' { + size++ + } + return +} + +func (p *Markdown) tableRow(data []byte, columns []CellAlignFlags, header bool) { + p.addBlock(TableRow, nil) + i, col := 0, 0 + + if data[i] == '|' && !isBackslashEscaped(data, i) { + i++ + } + + for col = 0; col < len(columns) && i < len(data); col++ { + for i < len(data) && data[i] == ' ' { + i++ + } + + cellStart := i + + for i < len(data) && (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 < len(data) && data[cellEnd-1] == ' ' { + cellEnd-- + } + + cell := p.addBlock(TableCell, data[cellStart:cellEnd]) + cell.IsHeader = header + cell.Align = columns[col] + } + + // pad it out with empty columns to get the right number + for ; col < len(columns); col++ { + cell := p.addBlock(TableCell, nil) + cell.IsHeader = header + cell.Align = columns[col] + } + + // silently ignore rows with too many cells +} + +// returns blockquote prefix length +func (p *Markdown) quotePrefix(data []byte) int { + i := 0 + for i < 3 && i < len(data) && data[i] == ' ' { + i++ + } + if i < len(data) && data[i] == '>' { + if i+1 < len(data) && 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 *Markdown) 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 *Markdown) quote(data []byte) int { + block := p.addBlock(BlockQuote, nil) + 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++ + } + if end < len(data) && data[end] == '\n' { + end++ + } + 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 + } + p.block(raw.Bytes()) + p.finalize(block) + return end +} + +// returns prefix length for block code +func (p *Markdown) codePrefix(data []byte) int { + if len(data) >= 1 && data[0] == '\t' { + return 1 + } + if len(data) >= 4 && data[0] == ' ' && data[1] == ' ' && data[2] == ' ' && data[3] == ' ' { + return 4 + } + return 0 +} + +func (p *Markdown) code(data []byte) int { + var work bytes.Buffer + + i := 0 + for i < len(data) { + beg := i + for i < len(data) && data[i] != '\n' { + i++ + } + if i < len(data) && data[i] == '\n' { + i++ + } + + 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 := len(workbytes) + for eol > 0 && workbytes[eol-1] == '\n' { + eol-- + } + if eol != len(workbytes) { + work.Truncate(eol) + } + + work.WriteByte('\n') + + block := p.addBlock(CodeBlock, work.Bytes()) // TODO: get rid of temp buffer + block.IsFenced = false + finalizeCodeBlock(block) + + return i +} + +// returns unordered list item prefix +func (p *Markdown) uliPrefix(data []byte) int { + i := 0 + // start with up to 3 spaces + for i < len(data) && i < 3 && data[i] == ' ' { + i++ + } + 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 *Markdown) oliPrefix(data []byte) int { + i := 0 + + // start with up to 3 spaces + for i < 3 && i < len(data) && data[i] == ' ' { + i++ + } + + // 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 *Markdown) dliPrefix(data []byte) int { + if len(data) < 2 { + return 0 + } + i := 0 + // need a ':' followed by a space or a tab + if data[i] != ':' || !(data[i+1] == ' ' || data[i+1] == '\t') { + return 0 + } + for i < len(data) && data[i] == ' ' { + i++ + } + return i + 2 +} + +// parse ordered or unordered list block +func (p *Markdown) list(data []byte, flags ListType) int { + i := 0 + flags |= ListItemBeginningOfList + block := p.addBlock(List, nil) + block.ListFlags = flags + block.Tight = true + + for i < len(data) { + skip := p.listItem(data[i:], &flags) + if flags&ListItemContainsBlock != 0 { + block.ListData.Tight = false + } + i += skip + if skip == 0 || flags&ListItemEndOfList != 0 { + break + } + flags &= ^ListItemBeginningOfList + } + + above := block.Parent + finalizeList(block) + p.tip = above + return i +} + +// Returns true if block ends with a blank line, descending if needed +// into lists and sublists. +func endsWithBlankLine(block *Node) bool { + // TODO: figure this out. Always false now. + for block != nil { + //if block.lastLineBlank { + //return true + //} + t := block.Type + if t == List || t == Item { + block = block.LastChild + } else { + break + } + } + return false +} + +func finalizeList(block *Node) { + block.open = false + item := block.FirstChild + for item != nil { + // check for non-final list item ending with blank line: + if endsWithBlankLine(item) && item.Next != nil { + block.ListData.Tight = false + break + } + // recurse into children of list item, to see if there are spaces + // between any of them: + subItem := item.FirstChild + for subItem != nil { + if endsWithBlankLine(subItem) && (item.Next != nil || subItem.Next != nil) { + block.ListData.Tight = false + break + } + subItem = subItem.Next + } + item = item.Next + } +} + +// Parse a single list item. +// Assumes initial prefix is already removed if this is a sublist. +func (p *Markdown) listItem(data []byte, flags *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 &= ^ListTypeTerm + } + } + if i == 0 { + // if in definition list, set term flag and continue + if *flags&ListTypeDefinition != 0 { + *flags |= ListTypeTerm + } else { + return 0 + } + } + + // skip leading whitespace on first line + for i < len(data) && data[i] == ' ' { + 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: + + if containsBlankLine { + *flags |= ListItemContainsBlock + } + + // to be a nested list, it must be indented more + // if not, it is the next item in the same list + if indent <= itemIndent { + break gatherlines + } + + // is this the first item in the nested list? + if sublist == 0 { + sublist = raw.Len() + } + + // is this a nested prefix heading? + case p.isPrefixHeading(chunk): + // if the heading is not indented, it is not nested in the list + // and thus ends the list + if containsBlankLine && indent < 4 { + *flags |= ListItemEndOfList + break gatherlines + } + *flags |= 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&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] != ':' && data[next] != ':' { + *flags |= ListItemEndOfList + } + } else { + *flags |= ListItemEndOfList + } + break gatherlines + + // a blank line means this should be parsed as a block + case containsBlankLine: + raw.WriteByte('\n') + *flags |= 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() + + block := p.addBlock(Item, nil) + block.ListFlags = *flags + block.Tight = false + block.BulletChar = bulletChar + block.Delimiter = '.' // Only '.' is possible in Markdown, but ')' will also be possible in CommonMark + + // render the contents of the list item + if *flags&ListItemContainsBlock != 0 && *flags&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 + if sublist > 0 { + child := p.addChild(Paragraph, 0) + child.content = rawBytes[:sublist] + p.block(rawBytes[sublist:]) + } else { + child := p.addChild(Paragraph, 0) + child.content = rawBytes + } + } + return line +} + +// render a single paragraph that has already been parsed out +func (p *Markdown) renderParagraph(data []byte) { + if len(data) == 0 { + return + } + + // trim leading spaces + beg := 0 + for data[beg] == ' ' { + beg++ + } + + end := len(data) + // trim trailing newline + if data[len(data)-1] == '\n' { + end-- + } + + // trim trailing spaces + for end > beg && data[end-1] == ' ' { + end-- + } + + p.addBlock(Paragraph, data[beg:end]) +} + +func (p *Markdown) 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] == ':' { + return p.list(data[prev:], ListTypeDefinition) + } + } + + 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 = sanitized_anchor_name.Create(string(data[prev:eol])) + } + + block := p.addBlock(Heading, data[prev:eol]) + block.Level = level + block.HeadingID = id + + // find the end of the underline + for i < len(data) && data[i] != '\n' { + i++ + } + return i + } + } + + // 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.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 definition list item, prev line is a definition term + if p.extensions&DefinitionLists != 0 { + if p.dliPrefix(current) != 0 { + ret := p.list(data[prev:], ListTypeDefinition) + return ret + } + } + + // 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 +} + +func skipChar(data []byte, start int, char byte) int { + i := start + for i < len(data) && data[i] == char { + i++ + } + return i +} + +func skipUntilChar(text []byte, start int, char byte) int { + i := start + for i < len(text) && text[i] != char { + i++ + } + return i +} -- cgit v1.2.3