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Diffstat (limited to 'vendor/gopkg.in/russross/blackfriday.v2/markdown.go')
| -rw-r--r-- | vendor/gopkg.in/russross/blackfriday.v2/markdown.go | 950 |
1 files changed, 0 insertions, 950 deletions
diff --git a/vendor/gopkg.in/russross/blackfriday.v2/markdown.go b/vendor/gopkg.in/russross/blackfriday.v2/markdown.go deleted file mode 100644 index 58d2e45..0000000 --- a/vendor/gopkg.in/russross/blackfriday.v2/markdown.go +++ /dev/null @@ -1,950 +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": {}, - "del": {}, - "div": {}, - "dl": {}, - "fieldset": {}, - "form": {}, - "h1": {}, - "h2": {}, - "h3": {}, - "h4": {}, - "h5": {}, - "h6": {}, - "iframe": {}, - "ins": {}, - "math": {}, - "noscript": {}, - "ol": {}, - "pre": {}, - "p": {}, - "script": {}, - "style": {}, - "table": {}, - "ul": {}, - - // HTML5 - "address": {}, - "article": {}, - "aside": {}, - "canvas": {}, - "figcaption": {}, - "figure": {}, - "footer": {}, - "header": {}, - "hgroup": {}, - "main": {}, - "nav": {}, - "output": {}, - "progress": {}, - "section": {}, - "video": {}, -} - -// 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. -// Finally, there are inline footnotes such as: -// -// Inline footnotes^[Also supported.] provide a quick inline explanation, -// but are rendered at the bottom of the document. -// - -// 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 ishorizontalspace(c) || isverticalspace(c) -} - -// Test if a character is a horizontal whitespace character. -func ishorizontalspace(c byte) bool { - return c == ' ' || c == '\t' -} - -// Test if a character is a vertical character. -func isverticalspace(c byte) bool { - return 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] -} |