coffeecup

coffee = require 'coffee-script' {uglify, parser} = require 'uglify-js' coffeecup = null # Call this from the main script so that the compiler module can have access to # coffeecup exports (node does not allow circular imports). exports.setup = (cc) -> coffeecup = cc skeleton = ''' var __cc = { buffer: '' }; var text = function(txt) { if (typeof txt === 'string' || txt instanceof String) { __cc.buffer += txt; } else if (typeof txt === 'number' || txt instanceof Number) { __cc.buffer += txt.toString(); } }; var h = function(txt) { var escaped; if (typeof txt === 'string' || txt instanceof String) { escaped = txt.replace(/&/g, '&') .replace(/</g, '<') .replace(/>/g, '>') .replace(/"/g, '"'); } else { escaped = txt; } return escaped; }; var yield = function(f) { var temp_buffer = ''; var old_buffer = __cc.buffer; __cc.buffer = temp_buffer; f(); temp_buffer = __cc.buffer; __cc.buffer = old_buffer; return temp_buffer; }; ''' call_bound_func = (func) -> # function(){ <func> }.call(data) return ['call', ['dot', func, 'call'], [['name', 'data']]] # Represents compiled javascript code to be written to the template function. class Code constructor: (parent) -> @parent = parent @nodes = [] @line = '' # Returns the ast node for `text(<arg>);` call: (arg) -> return ['stat', ['call', ['name', 'text'], [arg]]] # Add `str` to the current line to be written append: (str) -> if @block? @block.append str else @line += str # Flush the buffered line to the array of nodes flush: -> if @block? @block.flush() else @merge_text ['string', @line] @line = '' # Wrap subsequent calls to `text()` in an if block open_if: (condition) -> @flush() if @block? @block.open_if condition else @block = new Code() @block.condition = condition # Close an if block close_if: -> @flush() if @block.block? @block.close_if() else @nodes.push ['if', @block.condition, ['block', @block.nodes]] delete @block # Wrap an ast node in a call to `text()` and add it to the array of nodes push: (node) -> @flush() if @block? @block.push node else @merge_text node # Merge text() calls on the nodes merge_text: (arg) -> # Split up string concatenation inside text(), it slows down the template if arg[0] is 'binary' and arg[1] is '+' @merge_text arg[2] arg = arg[3] # Try to merge strings with previous text() calls if l = @nodes.length prev = @nodes[l-1] # Test if previous node is a call to text() if prev[0] is 'stat' and prev[1][0] is 'call' and prev[1][1][0] is 'name' and prev[1][1][1] is 'text' oldArg = prev[1][2][0] # Test if the previous and current calls are static strings - if so, combine ok = ['string', 'num'] if oldArg[0] in ok and arg[0] in ok prev[1][2][0] = [ 'string', oldArg[1] + arg[1] ] return # We can't combine - just add a call to text() @nodes.push @call arg # If the parent statement ends with a semicolon and is not an argument # to a function, return the statements as separate nodes. Otherwise wrap them # in an anonymous function bound to the `data` object. get_nodes: -> @flush() if @parent[0] is 'stat' return ['splice', @nodes] return call_bound_func([ 'function' null # Anonymous function [] # Takes no arguments @nodes ]) exports.compile = (source, hardcoded_locals, options) -> escape = (node) -> if options.autoescape # h(<node>) return ['call', ['name', 'h'], [node]] return node ast = parser.parse hardcoded_locals + "(#{source}).call(data);" w = uglify.ast_walker() ast = w.with_walkers call: (expr, args) -> name = expr[1] if name is 'doctype' code = new Code w.parent() if args.length > 0 doctype = args[0][1].toString() if doctype of coffeecup.doctypes code.append coffeecup.doctypes[doctype] else throw new Error 'Invalid doctype' else code.append coffeecup.doctypes.default return code.get_nodes() else if name is 'comment' comment = args[0] code = new Code w.parent() if comment[0] is 'string' code.append "" else code.append '' return code.get_nodes() else if name is 'ie' [condition, contents] = args code = new Code w.parent() if condition[0] is 'string' code.append "' return code.get_nodes() else if name in coffeecup.tags or name in ['tag', 'coffeescript'] if name is 'tag' name = args.shift()[1] # Compile coffeescript strings to js if name is 'coffeescript' name = 'script' for arg in args # Dynamically generated coffeescript not supported if arg[0] not in ['string', 'object', 'function'] throw new Error 'Invalid argument to coffeescript function' # Make sure this isn't an id class string, and compile it to js if arg[0] is 'string' and (args.length is 1 or arg isnt args[0]) arg[1] = coffee.compile arg[1], bare: yes code = new Code w.parent() code.append "<#{name}" # Iterate over the arguments to the tag function and build the tag html # as calls to the `text()` function. for arg in args switch arg[0] when 'function' # If this is a `<script>` tag, stringify the function if name is 'script' func = uglify.gen_code arg, beautify: true indent_level: 2 contents = ['string', "#{func}.call(this);"] # Otherwise recursively check for tag functions and inject the # result as a bound function call, escaping return values if necessary else func = w.walk arg # Escape return values unless they are hardcoded strings for node, idx in func[3] if node[0] is 'return' and node[1]? and node[1][0] != 'string' func[3][idx][1] = escape node[1] contents = call_bound_func(func) when 'object' render_attrs = (obj, prefix = '') -> for attr in obj key = attr[0] value = attr[1] # `true` is rendered as `selected="selected"`. if value[0] is 'name' and value[1] is 'true' code.append " #{key}=\"#{key}\"" # Do not render boolean false values else if value[0] is 'name' and value[1] in ['undefined', 'null', 'false'] continue # Wrap variables in a conditional block to make sure they are set else if value[0] in ['name', 'dot'] varname = uglify.gen_code value # Here we write the `if` condition in js and parse it, as # writing the nodes manually is tedious and hard to read condition = "typeof #{varname} !== 'undefined' && #{varname} !== null && #{varname} !== false" code.open_if parser.parse(condition)[1][0][1] # Strip 'toplevel' and 'stat' labels code.append " #{prefix + key}=\"" code.push escape value code.append '"' code.close_if() # If `value` is a simple string, include it in the same call to # `text` as the tag else if value[0] is 'string' code.append " #{prefix + key}=\"#{value[1]}\"" # Functions are prerendered as text else if value[0] is 'function' func = uglify.gen_code(value).replace(/"/g, '"') code.append " #{prefix + key}=\"#{func}.call(this);\"" # Prefixed attribute else if value[0] is 'object' # `data: {icon: 'foo'}` is rendered as `data-icon="foo"`. render_attrs value[1], prefix + key + '-' else code.append " #{prefix + key}=\"" code.push escape value code.append '"' render_attrs arg[1] when 'string' # id class string: `"#id.class1.class2"`. Note that this compiler # only supports hardcoded string values: if you need to determine # this tag's id or class dynamically, pass the value in an object # e.g. `div id: @getId(), class: getClasses()` if args.length > 1 and arg is args[0] classes = [] for i in arg[1].split '.' if '#' in i id = i.replace '#', '' else classes.push i unless i is '' code.append " id=\"#{id}\"" if id if classes.length > 0 code.append " class=\"#{classes.join ' '}\"" # Hardcoded string, escape and render it. else arg[1] = arg[1].replace(/&/g, '&') .replace(/</g, '<') .replace(/>/g, '>') .replace(/"/g, '"') contents = arg # A concatenated string e.g. `"id-" + @id` when 'binary' # Traverse the ast nodes, selectively escaping anything other # than hardcoded strings and calls to `yield`. escape_all = (node) -> switch node[0] when 'binary' node[2] = escape_all node[2] node[3] = escape_all node[3] return node when 'string' return node when 'call' if node[1][0] is 'name' and node[1][1] is 'yield' return node return escape node else return escape node contents = escape_all w.walk arg # For everything else, put into the template function as is. Note # that the `text()` function in the template skeleton will only # output strings and numbers. else contents = escape w.walk arg if name in coffeecup.self_closing code.append ' />' else code.append '>' code.push contents if contents? if not (name in coffeecup.self_closing) code.append "</#{name}>" return code.get_nodes() # Return the node as-is if this is not a call to a tag function return null , -> return w.walk ast compiled = uglify.gen_code ast, beautify: true indent_level: 2 # Main function assembly. if options.locals compiled = "with(data.locals){#{compiled}}" code = skeleton + compiled + "return __cc.buffer;" return new Function 'data', code