Files
lodash/build.js
John-David Dalton fe6aa8a6fc Further optimize _.template by controlling how the with-statement is inserted.
Former-commit-id: a62331e771302f9390d5aca04f878b839fe11b69
2012-07-05 11:28:41 -04:00

761 lines
23 KiB
JavaScript
Executable File

#!/usr/bin/env node
;(function() {
'use strict';
/** The Node filesystem and path modules */
var fs = require('fs'),
path = require('path');
/** Load other modules */
var lodash = require(path.join(__dirname, 'lodash')),
minify = require(path.join(__dirname, 'build', 'minify'));
/** Shortcut used to convert array-like objects to arrays */
var slice = [].slice;
/** The lodash.js source */
var source = fs.readFileSync(path.join(__dirname, 'lodash.js'), 'utf8');
/** Used to associate aliases with their real names */
var aliasToRealMap = {
'all': 'every',
'any': 'some',
'collect': 'map',
'detect': 'find',
'each': 'forEach',
'foldl': 'reduce',
'foldr': 'reduceRight',
'head': 'first',
'include': 'contains',
'inject': 'reduce',
'methods': 'functions',
'select': 'filter',
'tail': 'rest',
'take': 'first',
'unique': 'uniq'
};
/** Used to associate real names with their aliases */
var realToAliasMap = {
'contains': ['include'],
'every': ['all'],
'filter': ['select'],
'find': ['detect'],
'first': ['head', 'take'],
'forEach': ['each'],
'functions': ['methods'],
'map': ['collect'],
'reduce': ['foldl', 'inject'],
'reduceRight': ['foldr'],
'rest': ['tail'],
'some': ['any'],
'uniq': ['unique']
};
/** Used to track Backbone's Lo-Dash dependencies */
var backboneDependencies = [
'bind',
'bindAll',
'clone',
'contains',
'escape',
'every',
'extend',
'filter',
'find',
'first',
'forEach',
'groupBy',
'has',
'indexOf',
'initial',
'invoke',
'isArray',
'isEmpty',
'isEqual',
'isFunction',
'isObject',
'isRegExp',
'keys',
'last',
'lastIndexOf',
'map',
'max',
'min',
'mixin',
'reduce',
'reduceRight',
'reject',
'rest',
'shuffle',
'size',
'some',
'sortBy',
'sortedIndex',
'toArray',
'uniqueId',
'without'
];
/** Used to track function dependencies */
var dependencyMap = {
'after': [],
'bind': [],
'bindAll': ['bind', 'functions'],
'chain': ['mixin'],
'clone': ['extend', 'isArray'],
'compact': [],
'compose': [],
'contains': [],
'debounce': [],
'defaults': [],
'defer': [],
'delay': [],
'difference': ['indexOf'],
'escape': [],
'every': ['identity'],
'extend': [],
'filter': ['identity'],
'find': [],
'first': [],
'flatten': ['isArray'],
'forEach': [],
'forIn': [],
'forOwn': [],
'functions': [],
'groupBy': [],
'has': [],
'identity': [],
'indexOf': ['sortedIndex'],
'initial': [],
'intersection': ['every', 'indexOf'],
'invoke': [],
'isArguments': [],
'isArray': [],
'isBoolean': [],
'isDate': [],
'isElement': [],
'isEmpty': [],
'isEqual': [],
'isFinite': [],
'isFunction': [],
'isNaN': [],
'isNull': [],
'isNumber': [],
'isObject': [],
'isRegExp': [],
'isString': [],
'isUndefined': [],
'keys': [],
'last': [],
'lastIndexOf': [],
'map': ['identity'],
'max': [],
'memoize': [],
'min': [],
'mixin': ['forEach', 'functions'],
'noConflict': [],
'once': [],
'partial': [],
'pick': [],
'pluck': [],
'range': [],
'reduce': [],
'reduceRight': ['keys'],
'reject': ['identity'],
'rest': [],
'result': [],
'shuffle': [],
'size': ['keys'],
'some': ['identity'],
'sortBy': [],
'sortedIndex': ['bind'],
'tap': [],
'template': ['escape'],
'throttle': [],
'times': [],
'toArray': ['values'],
'union': ['indexOf'],
'uniq': ['identity', 'indexOf'],
'uniqueId': [],
'values': [],
'without': ['indexOf'],
'wrap': [],
'zip': ['max', 'pluck'],
'zipObject': []
};
/** Used to `iteratorTemplate` */
var iteratorOptions = [
'args',
'array',
'arrayBranch',
'beforeLoop',
'bottom',
'exit',
'firstArg',
'hasExp',
'hasDontEnumBug',
'inLoop',
'init',
'iteratedObject',
'loopExp',
'object',
'objectBranch',
'shadowed',
'top',
'useHas'
];
/** Collections of method names */
var excludeMethods,
includeMethods,
allMethods = Object.keys(dependencyMap);
/** Used to specify whether filtering is for exclusion or inclusion */
var filterType = process.argv.reduce(function(result, value) {
if (result) {
return result;
}
var pair = value.match(/^(exclude|include)=(.*)$/);
if (!pair) {
return result;
}
// remove nonexistent method names
var methodNames = lodash.intersection(allMethods, pair[2].split(/, */).map(getRealName));
if (pair[1] == 'exclude') {
excludeMethods = methodNames;
} else {
includeMethods = methodNames;
}
// return `filterType`
return pair[1];
}, '');
/** Flag used to specify a backbone build */
var isBackbone = process.argv.indexOf('backbone') > -1;
/** Flag used to specify a mobile build */
var isMobile = process.argv.indexOf('mobile') > -1;
/*--------------------------------------------------------------------------*/
/**
* Gets the aliases associated with a given `funcName`.
*
* @private
* @param {String} funcName The name of the function to get aliases for.
* @returns {Array} Returns an array of aliases.
*/
function getAliases(funcName) {
return realToAliasMap[funcName] || [];
}
/**
* Gets an array of depenants for a function by the given `funcName`.
*
* @private
* @param {String} funcName The name of the function to query.
* @returns {Array} Returns an array of function dependants.
*/
function getDependants(funcName) {
// iterate over `dependencyMap`, adding the names of functions that
// have `funcName` as a dependency
return lodash.reduce(dependencyMap, function(result, dependencies, otherName) {
if (lodash.contains(dependencies, funcName)) {
result.push(otherName);
}
return result;
}, []);
}
/**
* Gets an array of dependencies for a given function name. If passed an array
* of dependencies it will return an array containing the given dependencies
* plus any additional detected sub-dependencies.
*
* @private
* @param {Array|String} funcName A single function name or array of
* dependencies to query.
* @returns {Array} Returns an array of function dependencies.
*/
function getDependencies(funcName) {
var dependencies = Array.isArray(funcName) ? funcName : dependencyMap[funcName];
if (!dependencies) {
return [];
}
// recursively accumulate the dependencies of the `funcName` function, and
// the dependencies of its dependencies, and so on.
return lodash.uniq(dependencies.reduce(function(result, otherName) {
result.push.apply(result, getDependencies(otherName).concat(otherName));
return result;
}, []));
}
/**
* Gets the formatted source of the given function.
*
* @private
* @param {Function} func The function to process.
* @returns {String} Returns the formatted source.
*/
function getFunctionSource(func) {
var source = func.source || (func + '');
return source.replace(/\n(?:.*)/g, function(match, index) {
match = match.slice(1);
return (
match == '}' && source.indexOf('}', index + 2) == -1 ? '\n ' : '\n '
) + match;
});
}
/**
* Gets the `_.isArguments` fallback snippet from `source`.
*
* @private
* @param {String} source The source to inspect.
* @returns {String} Returns the `isArguments` fallback snippet.
*/
function getIsArgumentsFallback(source) {
return (source.match(/(?: *\/\/.*)*\s*if *\(!(?:lodash\.)?isArguments[^)]+\)[\s\S]+?};?\s*}\n/) || [''])[0];
}
/**
* Gets the real name, not alias, of a given `funcName`.
*
* @private
* @param {String} funcName The name of the function to resolve.
* @returns {String} Returns the real name.
*/
function getRealName(funcName) {
return aliasToRealMap[funcName] || funcName;
}
/**
* Determines if all functions of the given names have been removed from `source`.
*
* @private
* @param {String} source The source to inspect.
* @param {String} [funcName1, funcName2, ...] The names of functions to check.
* @returns {Boolean} Returns `true` if all functions have been removed, else `false`.
*/
function isRemoved(source) {
return slice.call(arguments, 1).every(function(funcName) {
return !matchFunction(source, funcName);
});
}
/**
* Searches `source` for a `funcName` function declaration, expression, or
* assignment and returns the matched snippet.
*
* @private
* @param {String} source The source to inspect.
* @param {String} funcName The name of the function to match.
* @returns {String} Returns the matched function snippet.
*/
function matchFunction(source, funcName) {
var result = source.match(RegExp(
// match multi-line comment block (could be on a single line)
'\\n +/\\*[^*]*\\*+(?:[^/][^*]*\\*+)*/\\n' +
// begin non-capturing group
'(?:' +
// match a function declaration
'( +)function ' + funcName + '\\b[\\s\\S]+?\\n\\1}|' +
// match a variable declaration with `createIterator`
' +var ' + funcName + ' *=.*?createIterator\\((?:{|[a-zA-Z])[\\s\\S]+?\\);|' +
// match a variable declaration with function expression
'( +)var ' + funcName + ' *=.*?function[\\s\\S]+?\\n\\2};' +
// end non-capturing group
')\\n'
));
return result ? result[0] : '';
}
/**
* Removes the all references to `refName` from the `createIterator` source.
*
* @private
* @param {String} source The source to process.
* @param {String} refName The name of the reference to remove.
* @returns {String} Returns the modified source.
*/
function removeFromCreateIterator(source, refName) {
var snippet = matchFunction(source, 'createIterator').match(/Function\([\s\S]+$/)[0],
modified = snippet.replace(RegExp('\\b' + refName + '\\b,? *', 'g'), '');
return source.replace(snippet, modified);
}
/**
* Removes the `funcName` function declaration, expression, or assignment and
* associated code from `source`.
*
* @private
* @param {String} source The source to process.
* @param {String} funcName The name of the function to remove.
* @returns {String} Returns the source with the function removed.
*/
function removeFunction(source, funcName) {
var modified,
snippet = matchFunction(source, funcName);
// exit early if function is not found
if (!snippet) {
return source;
}
// remove function
source = source.replace(matchFunction(source, funcName), '');
// grab the method assignments snippet
snippet = source.match(/lodash\.VERSION *= *[\s\S]+?\/\*-+\*\/\n/)[0];
// remove assignment and aliases
modified = getAliases(funcName).concat(funcName).reduce(function(result, otherName) {
return result.replace(RegExp('(?:\\n *//.*\\s*)* *lodash\\.' + otherName + ' *= *.+\\n'), '');
}, snippet);
// replace with the modified snippet
source = source.replace(snippet, modified);
return removeFromCreateIterator(source, funcName);
}
/**
* Removes the `_.isArguments` fallback from `source`.
*
* @private
* @param {String} source The source to process.
* @returns {String} Returns the source with the `isArguments` fallback removed.
*/
function removeIsArgumentsFallback(source) {
return source.replace(getIsArgumentsFallback(source), '');
}
/**
* Removes a given variable from `source`.
*
* @private
* @param {String} source The source to process.
* @param {String} varName The name of the variable to remove.
* @returns {String} Returns the source with the variable removed.
*/
function removeVar(source, varName) {
source = source.replace(RegExp(
// begin non-capturing group
'(?:' +
// match multi-line comment block
'(?:\\n +/\\*[^*]*\\*+(?:[^/][^*]*\\*+)*/)?\\n' +
// match a variable declaration that's not part of a declaration list
'( +)var ' + varName + ' *= *(?:.*?;|(?:Function\\(.+?|.*?[^,])\\n[\\s\\S]+?\\n\\1.+?;)\\n|' +
// match a variable in a declaration list
'\\n +' + varName + ' *=.*?,' +
// end non-capturing group
')'
), '');
// remove a varaible at the start of a variable declaration list
source = source.replace(RegExp('(var +)' + varName + ' *=.+?,\\s+'), '$1');
// remove a variable at the end of a variable declaration list
source = source.replace(RegExp(',\\s*' + varName + ' *=.*?;'), ';');
return removeFromCreateIterator(source, varName);
}
/*--------------------------------------------------------------------------*/
// Backbone build
if (isBackbone) {
// add any additional dependencies
backboneDependencies = getDependencies(backboneDependencies);
if (filterType == 'exclude') {
// remove excluded methods from `backboneDependencies`
includeMethods = lodash.without.apply(lodash, [backboneDependencies].concat(excludeMethods));
}
else if (filterType) {
// merge backbone dependencies into `includeMethods`
includeMethods = lodash.union(includeMethods, backboneDependencies);
}
else {
// include only the Backbone dependencies
includeMethods = backboneDependencies;
}
filterType = 'include';
}
/*--------------------------------------------------------------------------*/
// add category methods
process.argv.some(function(value) {
var categories = value.match(/^category=(.*)$/);
if (!categories) {
return false;
}
// resolve method names belonging to each category
var categoryMethods = categories.reduce(function(result, category) {
return result.concat(allMethods.filter(function(funcName) {
return RegExp('@category ' + category + '\\b', 'i').test(matchFunction(source, funcName));
}));
}, []);
if (filterType == 'exclude') {
// remove excluded methods from `categoryMethods`
includeMethods = lodash.without.apply(lodash, [categoryMethods].concat(excludeMethods));
}
else if (filterType) {
// merge backbone dependencies into `includeMethods`
includeMethods = lodash.union(includeMethods, categoryMethods);
}
else {
// include only the Backbone dependencies
includeMethods = categoryMethods;
}
filterType = 'include';
return true;
});
/*--------------------------------------------------------------------------*/
// custom build
(function() {
// exit early if "exclude" or "include" options aren't specified
if (!filterType) {
return;
}
if (filterType == 'exclude') {
// remove methods that are named in `excludeMethods` and their dependants
excludeMethods.forEach(function(funcName) {
getDependants(funcName).concat(funcName).forEach(function(otherName) {
source = removeFunction(source, otherName);
});
});
}
else {
// add dependencies to `includeMethods`
includeMethods = getDependencies(includeMethods);
// remove methods that aren't named in `includeMethods`
lodash.each(allMethods, function(otherName) {
if (!lodash.contains(includeMethods, otherName)) {
source = removeFunction(source, otherName);
}
});
}
// remove associated functions, variables and code snippets
if (isRemoved(source, 'isArguments')) {
source = removeIsArgumentsFallback(source);
}
if (isRemoved(source, 'mixin')) {
// remove `LoDash` constructor
source = removeFunction(source, 'LoDash');
// remove `LoDash` calls
source = source.replace(/(?:new +LoDash(?!\()|(?:new +)?LoDash\([^)]*\));?/g, '');
// remove `LoDash.prototype` additions
source = source.replace(/(?:\s*\/\/.*)*\s*LoDash.prototype *=[\s\S]+?\/\*-+\*\//, '');
}
if (isRemoved(source, 'template')) {
// remove `templateSettings` assignment
source = source.replace(/(?:\n +\/\*[^*]*\*+(?:[^\/][^*]*\*+)*\/)?\n *lodash\.templateSettings[\s\S]+?};\n/, '');
}
if (isRemoved(source, 'isArray', 'isEmpty', 'isEqual', 'size')) {
source = removeVar(source, 'arrayClass');
}
if (isRemoved(source, 'bind', 'functions', 'groupBy', 'invoke', 'isEqual', 'isFunction', 'result', 'sortBy', 'toArray')) {
source = removeVar(source, 'funcClass');
}
if (isRemoved(source, 'bind')) {
source = removeVar(source, 'nativeBind');
source = removeVar(source, 'useNativeBind');
}
if (isRemoved(source, 'isArray')) {
source = removeVar(source, 'nativeIsArray');
}
if (isRemoved(source, 'keys')) {
source = removeVar(source, 'nativeKeys');
}
if (isRemoved(source, 'clone', 'isObject', 'keys')) {
source = removeVar(source, 'objectTypes');
source = removeFromCreateIterator(source, 'objectTypes');
}
if (isRemoved(source, 'bind', 'isArray', 'keys')) {
source = removeVar(source, 'reNative');
}
if (isRemoved(source, 'isEmpty', 'isEqual', 'isString', 'size')) {
source = removeVar(source, 'stringClass');
}
// consolidate consecutive horizontal rule comment separators
source = source.replace(/(?:\s*\/\*-+\*\/\s*){2,}/g, function(separators) {
return separators.match(/^\s*/)[0] + separators.slice(separators.lastIndexOf('/*'));
});
}());
/*--------------------------------------------------------------------------*/
// simplify template snippets
source = source.replace(
RegExp(
"'else if \\(thisArg\\) \\{\\\\n' \\+\\s*" +
"' callback = iteratorBind\\(callback, thisArg\\)\\\\n' \\+\\s*" +
"'}'"
, 'g'),
"'else if (thisArg) callback = iteratorBind(callback, thisArg)'"
);
/*--------------------------------------------------------------------------*/
// DRY out isType methods
(function() {
var iteratorName = lodash.find(['forEach', 'forOwn'], function(funcName) {
return !isRemoved(source, funcName);
});
// skip this optimization if there is no iteration method to use
if (!iteratorName) {
return;
}
var snippet,
funcNames = [],
result = [],
token = '__isTypeToken__';
// build replacement code
lodash.forOwn({
'Arguments': "'[object Arguments]'",
'Date': 'dateClass',
'Function': 'funcClass',
'Number': 'numberClass',
'RegExp': 'regexpClass',
'String': 'stringClass'
}, function(value, key) {
var funcName = 'is' + key,
funcCode = matchFunction(source, funcName);
if (funcCode) {
if (!snippet) {
// use snippet to mark the insert position
snippet = funcCode;
}
funcNames.push(funcName);
result.push("'" + key + "': " + value);
}
});
// skip this optimization if there are less than 2 functions
if (result.length < 2) {
return;
}
// add a token to mark the position to insert new code
source = source.replace(snippet, '\n' + token + '\n' + snippet);
// remove existing isType functions
funcNames.forEach(function(funcName) {
source = removeFunction(source, funcName);
});
// replace token with new DRY code
source = source.replace(token,
' // add `_.' + funcNames.join('`, `_.') + '`\n' +
' ' + iteratorName + '({\n ' + result.join(',\n ') + '\n }, function(className, key) {\n' +
" lodash['is' + key] = function(value) {\n" +
' return toString.call(value) == className;\n' +
' };\n' +
' });'
);
// tweak `isArguments` fallback
snippet = getIsArgumentsFallback(source);
if (snippet) {
result = '\n' + snippet.replace(/isArguments/g, 'lodash.$&');
source = source.replace(snippet, result);
}
}());
/*--------------------------------------------------------------------------*/
if (isMobile) {
// inline functions defined with `createIterator`
lodash.functions(lodash).forEach(function(funcName) {
// match `funcName` with pseudo private `_` prefixes removed to allow matching `shimKeys`
var reFunc = RegExp('(\\bvar ' + funcName.replace(/^_/, '') + ' *= *)createIterator\\(((?:{|[a-zA-Z])[\\s\\S]+?)\\);\\n');
// skip if not defined with `createIterator`
if (!reFunc.test(source)) {
return;
}
// extract, format, and inject the compiled function's source code
source = source.replace(reFunc, '$1' + getFunctionSource(lodash[funcName]) + ';\n');
});
source = removeIsArgumentsFallback(source);
source = removeVar(source, 'iteratorTemplate');
// remove JScript [[DontEnum]] fix from `isEqual`
source = source.replace(/(?:\s*\/\/.*\n)*( +)if *\(result *&& *hasDontEnumBug[\s\S]+?\n\1}/, '');
// remove IE `shift` and `splice` fix
source = source.replace(/(?:\s*\/\/.*\n)*( +)if *\(value.length *=== *0[\s\S]+?\n\1}/, '');
// cleanup code
source = source.replace(/^ *;\n/gm, '');
}
else {
// inline `iteratorTemplate` template
source = source.replace(/(( +)var iteratorTemplate *= *)[\s\S]+?\n\2.+?;\n/, (function() {
var code = getFunctionSource(lodash._iteratorTemplate);
// expand properties to avoid having to use a with-statement
iteratorOptions.forEach(function(property) {
code = code.replace(RegExp('([^\\w.])\\b' + property + '\\b', 'g'), '$1obj.' + property);
});
// remove unnecessary code
code = code
.replace(/, *__t,[^;]+|function print[^}]+}/g, '')
.replace(/'(?:\\n|\s)+'/g, "''")
.replace(/__p *\+= *' *';/g, '')
.replace(/(__p *\+= *)' *' *\+/g, '$1')
.replace(/(\{) *;|; *(\})/g, '$1$2')
.replace(/\(\(__w?t *= *\( *([^)]+) *\)\) *== *null *\? *'' *: *__w?t\)/g, '$1');
// remove the with-statement
code = code.replace(/ *with *\([^)]+\) *{/, '\n').replace(/}}\s*;?\s*}/, '}}\n');
// minor cleanup
code = code
.replace(/obj *\|\| *\(obj *= *\{}\);/, '')
.replace(/var __p;\s*__p/, 'var __p');
// remove comments, including sourceURLs
code = code.replace(/\s*\/\/.*(?:\n|$)/g, '');
return '$1' + code + ';\n';
}()));
}
/*--------------------------------------------------------------------------*/
// remove pseudo private properties
source = source.replace(/(?:(?:\s*\/\/.*)*\s*lodash\._[^=]+=.+\n)+/g, '\n');
// begin the minification process
if (filterType || isBackbone || isMobile) {
fs.writeFileSync(path.join(__dirname, 'lodash.custom.js'), source);
minify(source, 'lodash.custom.min', function(result) {
fs.writeFileSync(path.join(__dirname, 'lodash.custom.min.js'), result);
});
}
else {
minify(source, 'lodash.min', function(result) {
fs.writeFileSync(path.join(__dirname, 'lodash.min.js'), result);
});
}
}());