--- a/vendor/github.com/russross/blackfriday/markdown.go Sun Jan 13 12:58:50 2019 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,940 +0,0 @@
-// Blackfriday Markdown Processor
-// Available at http://github.com/russross/blackfriday
-//
-// Copyright © 2011 Russ Ross <russ@russross.com>.
-// Distributed under the Simplified BSD License.
-// See README.md for details.
-
-package blackfriday
-
-import (
- "bytes"
- "fmt"
- "io"
- "strings"
- "unicode/utf8"
-)
-
-//
-// Markdown parsing and processing
-//
-
-// Version string of the package. Appears in the rendered document when
-// CompletePage flag is on.
-const Version = "2.0"
-
-// Extensions is a bitwise or'ed collection of enabled Blackfriday's
-// extensions.
-type Extensions int
-
-// These are the supported markdown parsing extensions.
-// OR these values together to select multiple extensions.
-const (
- NoExtensions Extensions = 0
- NoIntraEmphasis Extensions = 1 << iota // Ignore emphasis markers inside words
- Tables // Render tables
- FencedCode // Render fenced code blocks
- Autolink // Detect embedded URLs that are not explicitly marked
- Strikethrough // Strikethrough text using ~~test~~
- LaxHTMLBlocks // Loosen up HTML block parsing rules
- SpaceHeadings // Be strict about prefix heading rules
- HardLineBreak // Translate newlines into line breaks
- TabSizeEight // Expand tabs to eight spaces instead of four
- Footnotes // Pandoc-style footnotes
- NoEmptyLineBeforeBlock // No need to insert an empty line to start a (code, quote, ordered list, unordered list) block
- HeadingIDs // specify heading IDs with {#id}
- Titleblock // Titleblock ala pandoc
- AutoHeadingIDs // Create the heading ID from the text
- BackslashLineBreak // Translate trailing backslashes into line breaks
- DefinitionLists // Render definition lists
-
- CommonHTMLFlags HTMLFlags = UseXHTML | Smartypants |
- SmartypantsFractions | SmartypantsDashes | SmartypantsLatexDashes
-
- CommonExtensions Extensions = NoIntraEmphasis | Tables | FencedCode |
- Autolink | Strikethrough | SpaceHeadings | HeadingIDs |
- BackslashLineBreak | DefinitionLists
-)
-
-// ListType contains bitwise or'ed flags for list and list item objects.
-type ListType int
-
-// These are the possible flag values for the ListItem renderer.
-// Multiple flag values may be ORed together.
-// These are mostly of interest if you are writing a new output format.
-const (
- ListTypeOrdered ListType = 1 << iota
- ListTypeDefinition
- ListTypeTerm
-
- ListItemContainsBlock
- ListItemBeginningOfList // TODO: figure out if this is of any use now
- ListItemEndOfList
-)
-
-// CellAlignFlags holds a type of alignment in a table cell.
-type CellAlignFlags int
-
-// These are the possible flag values for the table cell renderer.
-// Only a single one of these values will be used; they are not ORed together.
-// These are mostly of interest if you are writing a new output format.
-const (
- TableAlignmentLeft CellAlignFlags = 1 << iota
- TableAlignmentRight
- TableAlignmentCenter = (TableAlignmentLeft | TableAlignmentRight)
-)
-
-// The size of a tab stop.
-const (
- TabSizeDefault = 4
- TabSizeDouble = 8
-)
-
-// 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.
-var blockTags = map[string]struct{}{
- "blockquote": struct{}{},
- "del": struct{}{},
- "div": struct{}{},
- "dl": struct{}{},
- "fieldset": struct{}{},
- "form": struct{}{},
- "h1": struct{}{},
- "h2": struct{}{},
- "h3": struct{}{},
- "h4": struct{}{},
- "h5": struct{}{},
- "h6": struct{}{},
- "iframe": struct{}{},
- "ins": struct{}{},
- "math": struct{}{},
- "noscript": struct{}{},
- "ol": struct{}{},
- "pre": struct{}{},
- "p": struct{}{},
- "script": struct{}{},
- "style": struct{}{},
- "table": struct{}{},
- "ul": struct{}{},
-
- // HTML5
- "address": struct{}{},
- "article": struct{}{},
- "aside": struct{}{},
- "canvas": struct{}{},
- "figcaption": struct{}{},
- "figure": struct{}{},
- "footer": struct{}{},
- "header": struct{}{},
- "hgroup": struct{}{},
- "main": struct{}{},
- "nav": struct{}{},
- "output": struct{}{},
- "progress": struct{}{},
- "section": struct{}{},
- "video": struct{}{},
-}
-
-// Renderer is the rendering interface. This is mostly of interest if you are
-// implementing a new rendering format.
-//
-// Only an HTML implementation is provided in this repository, see the README
-// for external implementations.
-type Renderer interface {
- // RenderNode is the main rendering method. It will be called once for
- // every leaf node and twice for every non-leaf node (first with
- // entering=true, then with entering=false). The method should write its
- // rendition of the node to the supplied writer w.
- RenderNode(w io.Writer, node *Node, entering bool) WalkStatus
-
- // RenderHeader is a method that allows the renderer to produce some
- // content preceding the main body of the output document. The header is
- // understood in the broad sense here. For example, the default HTML
- // renderer will write not only the HTML document preamble, but also the
- // table of contents if it was requested.
- //
- // The method will be passed an entire document tree, in case a particular
- // implementation needs to inspect it to produce output.
- //
- // The output should be written to the supplied writer w. If your
- // implementation has no header to write, supply an empty implementation.
- RenderHeader(w io.Writer, ast *Node)
-
- // RenderFooter is a symmetric counterpart of RenderHeader.
- RenderFooter(w io.Writer, ast *Node)
-}
-
-// Callback functions for inline parsing. One such function is defined
-// for each character that triggers a response when parsing inline data.
-type inlineParser func(p *Markdown, data []byte, offset int) (int, *Node)
-
-// Markdown is a type that holds extensions and the runtime state used by
-// Parse, and the renderer. You can not use it directly, construct it with New.
-type Markdown struct {
- renderer Renderer
- referenceOverride ReferenceOverrideFunc
- refs map[string]*reference
- inlineCallback [256]inlineParser
- extensions Extensions
- nesting int
- maxNesting int
- insideLink bool
-
- // Footnotes need to be ordered as well as available to quickly check for
- // presence. If a ref is also a footnote, it's stored both in refs and here
- // in notes. Slice is nil if footnotes not enabled.
- notes []*reference
-
- doc *Node
- tip *Node // = doc
- oldTip *Node
- lastMatchedContainer *Node // = doc
- allClosed bool
-}
-
-func (p *Markdown) getRef(refid string) (ref *reference, found bool) {
- if p.referenceOverride != nil {
- r, overridden := p.referenceOverride(refid)
- if overridden {
- if r == nil {
- return nil, false
- }
- return &reference{
- link: []byte(r.Link),
- title: []byte(r.Title),
- noteID: 0,
- hasBlock: false,
- text: []byte(r.Text)}, true
- }
- }
- // refs are case insensitive
- ref, found = p.refs[strings.ToLower(refid)]
- return ref, found
-}
-
-func (p *Markdown) finalize(block *Node) {
- above := block.Parent
- block.open = false
- p.tip = above
-}
-
-func (p *Markdown) addChild(node NodeType, offset uint32) *Node {
- return p.addExistingChild(NewNode(node), offset)
-}
-
-func (p *Markdown) addExistingChild(node *Node, offset uint32) *Node {
- for !p.tip.canContain(node.Type) {
- p.finalize(p.tip)
- }
- p.tip.AppendChild(node)
- p.tip = node
- return node
-}
-
-func (p *Markdown) closeUnmatchedBlocks() {
- if !p.allClosed {
- for p.oldTip != p.lastMatchedContainer {
- parent := p.oldTip.Parent
- p.finalize(p.oldTip)
- p.oldTip = parent
- }
- p.allClosed = true
- }
-}
-
-//
-//
-// Public interface
-//
-//
-
-// Reference represents the details of a link.
-// See the documentation in Options for more details on use-case.
-type Reference struct {
- // Link is usually the URL the reference points to.
- Link string
- // Title is the alternate text describing the link in more detail.
- Title string
- // Text is the optional text to override the ref with if the syntax used was
- // [refid][]
- Text string
-}
-
-// ReferenceOverrideFunc is expected to be called with a reference string and
-// return either a valid Reference type that the reference string maps to or
-// nil. If overridden is false, the default reference logic will be executed.
-// See the documentation in Options for more details on use-case.
-type ReferenceOverrideFunc func(reference string) (ref *Reference, overridden bool)
-
-// New constructs a Markdown processor. You can use the same With* functions as
-// for Run() to customize parser's behavior and the renderer.
-func New(opts ...Option) *Markdown {
- var p Markdown
- for _, opt := range opts {
- opt(&p)
- }
- p.refs = make(map[string]*reference)
- p.maxNesting = 16
- p.insideLink = false
- docNode := NewNode(Document)
- p.doc = docNode
- p.tip = docNode
- p.oldTip = docNode
- p.lastMatchedContainer = docNode
- p.allClosed = true
- // register inline parsers
- p.inlineCallback[' '] = maybeLineBreak
- p.inlineCallback['*'] = emphasis
- p.inlineCallback['_'] = emphasis
- if p.extensions&Strikethrough != 0 {
- p.inlineCallback['~'] = emphasis
- }
- p.inlineCallback['`'] = codeSpan
- p.inlineCallback['\n'] = lineBreak
- p.inlineCallback['['] = link
- p.inlineCallback['<'] = leftAngle
- p.inlineCallback['\\'] = escape
- p.inlineCallback['&'] = entity
- p.inlineCallback['!'] = maybeImage
- p.inlineCallback['^'] = maybeInlineFootnote
- if p.extensions&Autolink != 0 {
- p.inlineCallback['h'] = maybeAutoLink
- p.inlineCallback['m'] = maybeAutoLink
- p.inlineCallback['f'] = maybeAutoLink
- p.inlineCallback['H'] = maybeAutoLink
- p.inlineCallback['M'] = maybeAutoLink
- p.inlineCallback['F'] = maybeAutoLink
- }
- if p.extensions&Footnotes != 0 {
- p.notes = make([]*reference, 0)
- }
- return &p
-}
-
-// Option customizes the Markdown processor's default behavior.
-type Option func(*Markdown)
-
-// WithRenderer allows you to override the default renderer.
-func WithRenderer(r Renderer) Option {
- return func(p *Markdown) {
- p.renderer = r
- }
-}
-
-// WithExtensions allows you to pick some of the many extensions provided by
-// Blackfriday. You can bitwise OR them.
-func WithExtensions(e Extensions) Option {
- return func(p *Markdown) {
- p.extensions = e
- }
-}
-
-// WithNoExtensions turns off all extensions and custom behavior.
-func WithNoExtensions() Option {
- return func(p *Markdown) {
- p.extensions = NoExtensions
- p.renderer = NewHTMLRenderer(HTMLRendererParameters{
- Flags: HTMLFlagsNone,
- })
- }
-}
-
-// WithRefOverride sets an optional function callback that is called every
-// time a reference is resolved.
-//
-// In Markdown, the link reference syntax can be made to resolve a link to
-// a reference instead of an inline URL, in one of the following ways:
-//
-// * [link text][refid]
-// * [refid][]
-//
-// Usually, the refid is defined at the bottom of the Markdown document. If
-// this override function is provided, the refid is passed to the override
-// function first, before consulting the defined refids at the bottom. If
-// the override function indicates an override did not occur, the refids at
-// the bottom will be used to fill in the link details.
-func WithRefOverride(o ReferenceOverrideFunc) Option {
- return func(p *Markdown) {
- p.referenceOverride = o
- }
-}
-
-// Run is the main entry point to Blackfriday. It parses and renders a
-// block of markdown-encoded text.
-//
-// The simplest invocation of Run takes one argument, input:
-// output := Run(input)
-// This will parse the input with CommonExtensions enabled and render it with
-// the default HTMLRenderer (with CommonHTMLFlags).
-//
-// Variadic arguments opts can customize the default behavior. Since Markdown
-// type does not contain exported fields, you can not use it directly. Instead,
-// use the With* functions. For example, this will call the most basic
-// functionality, with no extensions:
-// output := Run(input, WithNoExtensions())
-//
-// You can use any number of With* arguments, even contradicting ones. They
-// will be applied in order of appearance and the latter will override the
-// former:
-// output := Run(input, WithNoExtensions(), WithExtensions(exts),
-// WithRenderer(yourRenderer))
-func Run(input []byte, opts ...Option) []byte {
- r := NewHTMLRenderer(HTMLRendererParameters{
- Flags: CommonHTMLFlags,
- })
- optList := []Option{WithRenderer(r), WithExtensions(CommonExtensions)}
- optList = append(optList, opts...)
- parser := New(optList...)
- ast := parser.Parse(input)
- var buf bytes.Buffer
- parser.renderer.RenderHeader(&buf, ast)
- ast.Walk(func(node *Node, entering bool) WalkStatus {
- return parser.renderer.RenderNode(&buf, node, entering)
- })
- parser.renderer.RenderFooter(&buf, ast)
- return buf.Bytes()
-}
-
-// Parse is an entry point to the parsing part of Blackfriday. It takes an
-// input markdown document and produces a syntax tree for its contents. This
-// tree can then be rendered with a default or custom renderer, or
-// analyzed/transformed by the caller to whatever non-standard needs they have.
-// The return value is the root node of the syntax tree.
-func (p *Markdown) Parse(input []byte) *Node {
- p.block(input)
- // Walk the tree and finish up some of unfinished blocks
- for p.tip != nil {
- p.finalize(p.tip)
- }
- // Walk the tree again and process inline markdown in each block
- p.doc.Walk(func(node *Node, entering bool) WalkStatus {
- if node.Type == Paragraph || node.Type == Heading || node.Type == TableCell {
- p.inline(node, node.content)
- node.content = nil
- }
- return GoToNext
- })
- p.parseRefsToAST()
- return p.doc
-}
-
-func (p *Markdown) parseRefsToAST() {
- if p.extensions&Footnotes == 0 || len(p.notes) == 0 {
- return
- }
- p.tip = p.doc
- block := p.addBlock(List, nil)
- block.IsFootnotesList = true
- block.ListFlags = ListTypeOrdered
- flags := ListItemBeginningOfList
- // Note: this loop is intentionally explicit, not range-form. This is
- // because the body of the loop will append nested footnotes to p.notes and
- // we need to process those late additions. Range form would only walk over
- // the fixed initial set.
- for i := 0; i < len(p.notes); i++ {
- ref := p.notes[i]
- p.addExistingChild(ref.footnote, 0)
- block := ref.footnote
- block.ListFlags = flags | ListTypeOrdered
- block.RefLink = ref.link
- if ref.hasBlock {
- flags |= ListItemContainsBlock
- p.block(ref.title)
- } else {
- p.inline(block, ref.title)
- }
- flags &^= ListItemBeginningOfList | ListItemContainsBlock
- }
- above := block.Parent
- finalizeList(block)
- p.tip = above
- block.Walk(func(node *Node, entering bool) WalkStatus {
- if node.Type == Paragraph || node.Type == Heading {
- p.inline(node, node.content)
- node.content = nil
- }
- return GoToNext
- })
-}
-
-//
-// Link references
-//
-// This section implements support for references that (usually) appear
-// as footnotes in a document, and can be referenced anywhere in the document.
-// The basic format is:
-//
-// [1]: http://www.google.com/ "Google"
-// [2]: http://www.github.com/ "Github"
-//
-// Anywhere in the document, the reference can be linked by referring to its
-// label, i.e., 1 and 2 in this example, as in:
-//
-// This library is hosted on [Github][2], a git hosting site.
-//
-// Actual footnotes as specified in Pandoc and supported by some other Markdown
-// libraries such as php-markdown are also taken care of. They look like this:
-//
-// This sentence needs a bit of further explanation.[^note]
-//
-// [^note]: This is the explanation.
-//
-// Footnotes should be placed at the end of the document in an ordered list.
-// Inline footnotes such as:
-//
-// Inline footnotes^[Not supported.] also exist.
-//
-// are not yet supported.
-
-// reference holds all information necessary for a reference-style links or
-// footnotes.
-//
-// Consider this markdown with reference-style links:
-//
-// [link][ref]
-//
-// [ref]: /url/ "tooltip title"
-//
-// It will be ultimately converted to this HTML:
-//
-// <p><a href=\"/url/\" title=\"title\">link</a></p>
-//
-// And a reference structure will be populated as follows:
-//
-// p.refs["ref"] = &reference{
-// link: "/url/",
-// title: "tooltip title",
-// }
-//
-// Alternatively, reference can contain information about a footnote. Consider
-// this markdown:
-//
-// Text needing a footnote.[^a]
-//
-// [^a]: This is the note
-//
-// A reference structure will be populated as follows:
-//
-// p.refs["a"] = &reference{
-// link: "a",
-// title: "This is the note",
-// noteID: <some positive int>,
-// }
-//
-// TODO: As you can see, it begs for splitting into two dedicated structures
-// for refs and for footnotes.
-type reference struct {
- link []byte
- title []byte
- noteID int // 0 if not a footnote ref
- hasBlock bool
- footnote *Node // a link to the Item node within a list of footnotes
-
- text []byte // only gets populated by refOverride feature with Reference.Text
-}
-
-func (r *reference) String() string {
- return fmt.Sprintf("{link: %q, title: %q, text: %q, noteID: %d, hasBlock: %v}",
- r.link, r.title, r.text, r.noteID, r.hasBlock)
-}
-
-// Check whether or not data starts with a reference link.
-// If so, it is parsed and stored in the list of references
-// (in the render struct).
-// Returns the number of bytes to skip to move past it,
-// or zero if the first line is not a reference.
-func isReference(p *Markdown, data []byte, tabSize int) int {
- // up to 3 optional leading spaces
- if len(data) < 4 {
- return 0
- }
- i := 0
- for i < 3 && data[i] == ' ' {
- i++
- }
-
- noteID := 0
-
- // id part: anything but a newline between brackets
- if data[i] != '[' {
- return 0
- }
- i++
- if p.extensions&Footnotes != 0 {
- if i < len(data) && data[i] == '^' {
- // we can set it to anything here because the proper noteIds will
- // be assigned later during the second pass. It just has to be != 0
- noteID = 1
- i++
- }
- }
- idOffset := i
- for i < len(data) && data[i] != '\n' && data[i] != '\r' && data[i] != ']' {
- i++
- }
- if i >= len(data) || data[i] != ']' {
- return 0
- }
- idEnd := i
- // footnotes can have empty ID, like this: [^], but a reference can not be
- // empty like this: []. Break early if it's not a footnote and there's no ID
- if noteID == 0 && idOffset == idEnd {
- return 0
- }
- // spacer: colon (space | tab)* newline? (space | tab)*
- i++
- if i >= len(data) || data[i] != ':' {
- return 0
- }
- i++
- for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
- i++
- }
- if i < len(data) && (data[i] == '\n' || data[i] == '\r') {
- i++
- if i < len(data) && data[i] == '\n' && data[i-1] == '\r' {
- i++
- }
- }
- for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
- i++
- }
- if i >= len(data) {
- return 0
- }
-
- var (
- linkOffset, linkEnd int
- titleOffset, titleEnd int
- lineEnd int
- raw []byte
- hasBlock bool
- )
-
- if p.extensions&Footnotes != 0 && noteID != 0 {
- linkOffset, linkEnd, raw, hasBlock = scanFootnote(p, data, i, tabSize)
- lineEnd = linkEnd
- } else {
- linkOffset, linkEnd, titleOffset, titleEnd, lineEnd = scanLinkRef(p, data, i)
- }
- if lineEnd == 0 {
- return 0
- }
-
- // a valid ref has been found
-
- ref := &reference{
- noteID: noteID,
- hasBlock: hasBlock,
- }
-
- if noteID > 0 {
- // reusing the link field for the id since footnotes don't have links
- ref.link = data[idOffset:idEnd]
- // if footnote, it's not really a title, it's the contained text
- ref.title = raw
- } else {
- ref.link = data[linkOffset:linkEnd]
- ref.title = data[titleOffset:titleEnd]
- }
-
- // id matches are case-insensitive
- id := string(bytes.ToLower(data[idOffset:idEnd]))
-
- p.refs[id] = ref
-
- return lineEnd
-}
-
-func scanLinkRef(p *Markdown, data []byte, i int) (linkOffset, linkEnd, titleOffset, titleEnd, lineEnd int) {
- // link: whitespace-free sequence, optionally between angle brackets
- if data[i] == '<' {
- i++
- }
- linkOffset = i
- for i < len(data) && data[i] != ' ' && data[i] != '\t' && data[i] != '\n' && data[i] != '\r' {
- i++
- }
- linkEnd = i
- if data[linkOffset] == '<' && data[linkEnd-1] == '>' {
- linkOffset++
- linkEnd--
- }
-
- // optional spacer: (space | tab)* (newline | '\'' | '"' | '(' )
- for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
- i++
- }
- if i < len(data) && data[i] != '\n' && data[i] != '\r' && data[i] != '\'' && data[i] != '"' && data[i] != '(' {
- return
- }
-
- // compute end-of-line
- if i >= len(data) || data[i] == '\r' || data[i] == '\n' {
- lineEnd = i
- }
- if i+1 < len(data) && data[i] == '\r' && data[i+1] == '\n' {
- lineEnd++
- }
-
- // optional (space|tab)* spacer after a newline
- if lineEnd > 0 {
- i = lineEnd + 1
- for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
- i++
- }
- }
-
- // optional title: any non-newline sequence enclosed in '"() alone on its line
- if i+1 < len(data) && (data[i] == '\'' || data[i] == '"' || data[i] == '(') {
- i++
- titleOffset = i
-
- // look for EOL
- for i < len(data) && data[i] != '\n' && data[i] != '\r' {
- i++
- }
- if i+1 < len(data) && data[i] == '\n' && data[i+1] == '\r' {
- titleEnd = i + 1
- } else {
- titleEnd = i
- }
-
- // step back
- i--
- for i > titleOffset && (data[i] == ' ' || data[i] == '\t') {
- i--
- }
- if i > titleOffset && (data[i] == '\'' || data[i] == '"' || data[i] == ')') {
- lineEnd = titleEnd
- titleEnd = i
- }
- }
-
- return
-}
-
-// The first bit of this logic is the same as Parser.listItem, but the rest
-// is much simpler. This function simply finds the entire block and shifts it
-// over by one tab if it is indeed a block (just returns the line if it's not).
-// blockEnd is the end of the section in the input buffer, and contents is the
-// extracted text that was shifted over one tab. It will need to be rendered at
-// the end of the document.
-func scanFootnote(p *Markdown, data []byte, i, indentSize int) (blockStart, blockEnd int, contents []byte, hasBlock bool) {
- if i == 0 || len(data) == 0 {
- return
- }
-
- // skip leading whitespace on first line
- for i < len(data) && data[i] == ' ' {
- i++
- }
-
- blockStart = i
-
- // find the end of the line
- blockEnd = i
- for 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[blockEnd:i])
- blockEnd = i
-
- // process the following lines
- containsBlankLine := false
-
-gatherLines:
- for blockEnd < 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[blockEnd:i]) > 0 {
- containsBlankLine = true
- blockEnd = i
- continue
- }
-
- n := 0
- if n = isIndented(data[blockEnd:i], indentSize); n == 0 {
- // this is the end of the block.
- // we don't want to include this last line in the index.
- break gatherLines
- }
-
- // if there were blank lines before this one, insert a new one now
- if containsBlankLine {
- raw.WriteByte('\n')
- containsBlankLine = false
- }
-
- // get rid of that first tab, write to buffer
- raw.Write(data[blockEnd+n : i])
- hasBlock = true
-
- blockEnd = i
- }
-
- if data[blockEnd-1] != '\n' {
- raw.WriteByte('\n')
- }
-
- contents = raw.Bytes()
-
- return
-}
-
-//
-//
-// Miscellaneous helper functions
-//
-//
-
-// Test if a character is a punctuation symbol.
-// Taken from a private function in regexp in the stdlib.
-func ispunct(c byte) bool {
- for _, r := range []byte("!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~") {
- if c == r {
- return true
- }
- }
- return false
-}
-
-// Test if a character is a whitespace character.
-func isspace(c byte) bool {
- return c == ' ' || c == '\t' || c == '\n' || c == '\r' || c == '\f' || c == '\v'
-}
-
-// Test if a character is letter.
-func isletter(c byte) bool {
- return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')
-}
-
-// Test if a character is a letter or a digit.
-// TODO: check when this is looking for ASCII alnum and when it should use unicode
-func isalnum(c byte) bool {
- return (c >= '0' && c <= '9') || isletter(c)
-}
-
-// Replace tab characters with spaces, aligning to the next TAB_SIZE column.
-// always ends output with a newline
-func expandTabs(out *bytes.Buffer, line []byte, tabSize int) {
- // first, check for common cases: no tabs, or only tabs at beginning of line
- i, prefix := 0, 0
- slowcase := false
- for i = 0; i < len(line); i++ {
- if line[i] == '\t' {
- if prefix == i {
- prefix++
- } else {
- slowcase = true
- break
- }
- }
- }
-
- // no need to decode runes if all tabs are at the beginning of the line
- if !slowcase {
- for i = 0; i < prefix*tabSize; i++ {
- out.WriteByte(' ')
- }
- out.Write(line[prefix:])
- return
- }
-
- // the slow case: we need to count runes to figure out how
- // many spaces to insert for each tab
- column := 0
- i = 0
- for i < len(line) {
- start := i
- for i < len(line) && line[i] != '\t' {
- _, size := utf8.DecodeRune(line[i:])
- i += size
- column++
- }
-
- if i > start {
- out.Write(line[start:i])
- }
-
- if i >= len(line) {
- break
- }
-
- for {
- out.WriteByte(' ')
- column++
- if column%tabSize == 0 {
- break
- }
- }
-
- i++
- }
-}
-
-// Find if a line counts as indented or not.
-// Returns number of characters the indent is (0 = not indented).
-func isIndented(data []byte, indentSize int) int {
- if len(data) == 0 {
- return 0
- }
- if data[0] == '\t' {
- return 1
- }
- if len(data) < indentSize {
- return 0
- }
- for i := 0; i < indentSize; i++ {
- if data[i] != ' ' {
- return 0
- }
- }
- return indentSize
-}
-
-// Create a url-safe slug for fragments
-func slugify(in []byte) []byte {
- if len(in) == 0 {
- return in
- }
- out := make([]byte, 0, len(in))
- sym := false
-
- for _, ch := range in {
- if isalnum(ch) {
- sym = false
- out = append(out, ch)
- } else if sym {
- continue
- } else {
- out = append(out, '-')
- sym = true
- }
- }
- var a, b int
- var ch byte
- for a, ch = range out {
- if ch != '-' {
- break
- }
- }
- for b = len(out) - 1; b > 0; b-- {
- if out[b] != '-' {
- break
- }
- }
- return out[a : b+1]
-}