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Diffstat (limited to 'lexlua/html.lua')
| -rw-r--r-- | lexlua/html.lua | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/lexlua/html.lua b/lexlua/html.lua new file mode 100644 index 000000000..8c8d999c7 --- /dev/null +++ b/lexlua/html.lua @@ -0,0 +1,149 @@ +-- Copyright 2006-2018 Mitchell mitchell.att.foicica.com. See License.txt. +-- HTML LPeg lexer. + +local lexer = require('lexer') +local token, word_match = lexer.token, lexer.word_match +local P, R, S, V = lpeg.P, lpeg.R, lpeg.S, lpeg.V + +local lex = lexer.new('html') + +-- Whitespace. +local ws = token(lexer.WHITESPACE, lexer.space^1) +lex:add_rule('whitespace', ws) + +-- Comments. +lex:add_rule('comment', token(lexer.COMMENT, '<!--' * (lexer.any - '-->')^0 * + P('-->')^-1)) + +-- Doctype. +lex:add_rule('doctype', token('doctype', '<!' * word_match([[doctype]], true) * + (lexer.any - '>')^1 * '>')) +lex:add_style('doctype', lexer.STYLE_COMMENT) + +-- Elements. +local known_element = token('element', '<' * P('/')^-1 * word_match([[ + a abbr address area article aside audio b base bdi bdo blockquote body br + button canvas caption cite code col colgroup content data datalist dd + decorator del details dfn div dl dt element em embed fieldset figcaption + figure footer form h1 h2 h3 h4 h5 h6 head header hr html i iframe img input + ins kbd keygen label legend li link main map mark menu menuitem meta meter nav + noscript object ol optgroup option output p param pre progress q rp rt ruby s + samp script section select shadow small source spacer span strong style sub + summary sup table tbody td template textarea tfoot th thead time title tr + track u ul var video wbr +]], true)) +local unknown_element = token('unknown_element', '<' * P('/')^-1 * lexer.word) +local element = known_element + unknown_element +lex:add_rule('element', element) +lex:add_style('element', lexer.STYLE_KEYWORD) +lex:add_style('unknown_element', lexer.STYLE_KEYWORD..',italics') + +-- Closing tags. +local tag_close = token('element', P('/')^-1 * '>') +lex:add_rule('tag_close', tag_close) + +-- Attributes. +local known_attribute = token('attribute', word_match([[ + accept accept-charset accesskey action align alt async autocomplete autofocus + autoplay bgcolor border buffered challenge charset checked cite class code + codebase color cols colspan content contenteditable contextmenu controls + coords data data- datetime default defer dir dirname disabled download + draggable dropzone enctype for form headers height hidden high href hreflang + http-equiv icon id ismap itemprop keytype kind label lang language list loop + low manifest max maxlength media method min multiple name novalidate open + optimum pattern ping placeholder poster preload pubdate radiogroup readonly + rel required reversed role rows rowspan sandbox scope scoped seamless selected + shape size sizes span spellcheck src srcdoc srclang start step style summary + tabindex target title type usemap value width wrap +]], true) + ((P('data-') + 'aria-') * (lexer.alnum + '-')^1)) +local unknown_attribute = token('unknown_attribute', lexer.word) +local attribute = (known_attribute + unknown_attribute) * #(lexer.space^0 * '=') +lex:add_rule('attribute', attribute) +lex:add_style('attribute', lexer.STYLE_TYPE) +lex:add_style('unknown_attribute', lexer.STYLE_TYPE..',italics') + +-- TODO: performance is terrible on large files. +local in_tag = P(function(input, index) + local before = input:sub(1, index - 1) + local s, e = before:find('<[^>]-$'), before:find('>[^<]-$') + if s and e then return s > e and index or nil end + if s then return index end + return input:find('^[^<]->', index) and index or nil +end) + +-- Equals. +local equals = token(lexer.OPERATOR, '=') --* in_tag +--lex:add_rule('equals', equals) + +-- Strings. +local string = #S('\'"') * lexer.last_char_includes('=') * + token(lexer.STRING, lexer.delimited_range("'") + + lexer.delimited_range('"')) +lex:add_rule('string', string) + +-- Numbers. +lex:add_rule('number', #lexer.digit * lexer.last_char_includes('=') * + token(lexer.NUMBER, lexer.digit^1 * P('%')^-1))--*in_tag) + +-- Entities. +lex:add_rule('entity', token('entity', '&' * (lexer.any - lexer.space - ';')^1 * + ';')) +lex:add_style('entity', lexer.STYLE_COMMENT) + +-- Fold points. +local function disambiguate_lt(text, pos, line, s) + return not line:find('^</', s) and 1 or -1 +end +lex:add_fold_point('element', '<', disambiguate_lt) +lex:add_fold_point('element', '/>', -1) +lex:add_fold_point('unknown_element', '<', disambiguate_lt) +lex:add_fold_point('unknown_element', '/>', -1) +lex:add_fold_point(lexer.COMMENT, '<!--', '-->') + +-- Tags that start embedded languages. +-- Export these patterns for proxy lexers (e.g. ASP) that need them. +lex.embed_start_tag = element * + (ws * attribute * ws^-1 * equals * ws^-1 * string)^0 * + ws^-1 * tag_close +lex.embed_end_tag = element * tag_close + +-- Embedded CSS (<style type="text/css"> ... </style>). +local css = lexer.load('css') +local style_element = word_match([[style]], true) +local css_start_rule = #(P('<') * style_element * + ('>' + P(function(input, index) + if input:find('^%s+type%s*=%s*(["\'])text/css%1', index) then + return index + end +end))) * lex.embed_start_tag +local css_end_rule = #('</' * style_element * ws^-1 * '>') * lex.embed_end_tag +lex:embed(css, css_start_rule, css_end_rule) + +-- Embedded JavaScript (<script type="text/javascript"> ... </script>). +local js = lexer.load('javascript') +local script_element = word_match([[script]], true) +local js_start_rule = #(P('<') * script_element * + ('>' + P(function(input, index) + if input:find('^%s+type%s*=%s*(["\'])text/javascript%1', index) then + return index + end +end))) * lex.embed_start_tag +local js_end_rule = #('</' * script_element * ws^-1 * '>') * lex.embed_end_tag +local js_line_comment = '//' * (lexer.nonnewline_esc - js_end_rule)^0 +local js_block_comment = '/*' * (lexer.any - '*/' - js_end_rule)^0 * P('*/')^-1 +js:modify_rule('comment', token(lexer.COMMENT, js_line_comment + + js_block_comment)) +lex:embed(js, js_start_rule, js_end_rule) + +-- Embedded CoffeeScript (<script type="text/coffeescript"> ... </script>). +local cs = lexer.load('coffeescript') +local script_element = word_match([[script]], true) +local cs_start_rule = #(P('<') * script_element * P(function(input, index) + if input:find('^[^>]+type%s*=%s*(["\'])text/coffeescript%1', index) then + return index + end +end)) * lex.embed_start_tag +local cs_end_rule = #('</' * script_element * ws^-1 * '>') * lex.embed_end_tag +lex:embed(cs, cs_start_rule, cs_end_rule) + +return lex |