Files
lodash/build/pre-compile.js
John-David Dalton e4e41e5ef8 Cleanup _.template docs and generate less unused code in compiled templates.
Former-commit-id: e6703414b83e9286d9ce5e14214375bbbaf9285f
2012-08-19 02:13:43 -07:00

446 lines
13 KiB
JavaScript

#!/usr/bin/env node
;(function() {
'use strict';
/** The Node filesystem module */
var fs = require('fs');
/** Used to minify variables embedded in compiled strings */
var compiledVars = [
'callback',
'collection',
'concat',
'ctor',
'hasOwnProperty',
'identity',
'index',
'iteratee',
'iteratorBind',
'length',
'nativeKeys',
'object',
'ownIndex',
'ownProps',
'prop',
'propertyIsEnumerable',
'propIndex',
'props',
'result',
'skipProto',
'slice',
'stringClass',
'thisArg',
'toString',
'value',
// lesser used variables
'accumulator',
'args',
'argsIndex',
'argsLength',
'arrayLikeClasses',
'ArrayProto',
'bind',
'callee',
'className',
'compareAscending',
'destValue',
'forIn',
'found',
'funcs',
'indexOf',
'indicator',
'isArguments',
'isArr',
'isArray',
'isFunc',
'isFunction',
'isPlainObject',
'methodName',
'noaccum',
'objectClass',
'objectTypes',
'pass',
'properties',
'property',
'propsLength',
'recursive',
'source',
'stack',
'stackLength',
'target',
'valueProp'
];
/** Used to minify `compileIterator` option properties */
var iteratorOptions = [
'args',
'array',
'arrayBranch',
'beforeLoop',
'bottom',
'exit',
'firstArg',
'hasDontEnumBug',
'inLoop',
'init',
'isKeysFast',
'object',
'objectBranch',
'noArgsEnum',
'noCharByIndex',
'shadowed',
'top',
'useHas',
'useStrict'
];
/** Used to minify variables and string values to a single character */
var minNames = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'.split('');
minNames.push.apply(minNames, minNames.map(function(value) {
return value + value;
}));
/** Used to protect the specified properties from getting minified */
var propWhitelist = [
'_',
'_chain',
'_wrapped',
'after',
'all',
'amd',
'any',
'attachEvent',
'bind',
'bindAll',
'chain',
'clearTimeout',
'clone',
'collect',
'compact',
'compose',
'contains',
'countBy',
'criteria',
'debounce',
'defaults',
'defer',
'delay',
'detect',
'difference',
'drop',
'each',
'environment',
'escape',
'escape',
'evaluate',
'every',
'extend',
'filter',
'find',
'first',
'flatten',
'foldl',
'foldr',
'forEach',
'forIn',
'forOwn',
'functions',
'groupBy',
'has',
'head',
'identity',
'include',
'index',
'indexOf',
'initial',
'inject',
'interpolate',
'intersection',
'invoke',
'isArguments',
'isArray',
'isBoolean',
'isDate',
'isElement',
'isEmpty',
'isEqual',
'isEqual',
'isFinite',
'isFinite',
'isFunction',
'isNaN',
'isNull',
'isNumber',
'isObject',
'isRegExp',
'isString',
'isUndefined',
'keys',
'last',
'lastIndexOf',
'map',
'max',
'memoize',
'merge',
'methods',
'min',
'mixin',
'noConflict',
'once',
'opera',
'partial',
'pick',
'pluck',
'range',
'reduce',
'reduceRight',
'reject',
'rest',
'result',
'select',
'setTimeout',
'shuffle',
'size',
'some',
'sortBy',
'sortedIndex',
'source',
'tail',
'take',
'tap',
'template',
'templateSettings',
'throttle',
'times',
'toArray',
'union',
'uniq',
'unique',
'uniqueId',
'value',
'values',
'variable',
'VERSION',
'where',
'without',
'wrap',
'zip',
'zipObject'
];
/*--------------------------------------------------------------------------*/
/**
* Pre-process a given Lo-Dash `source`, preparing it for minification.
*
* @param {String} source The source to process.
* @returns {String} Returns the processed source.
*/
function preprocess(source) {
// remove copyright to add later in post-compile.js
source = source.replace(/\/\*![\s\S]+?\*\//, '');
// remove unrecognized JSDoc tags so Closure Compiler won't complain
source = source.replace(/@(?:alias|category)\b.*/g, '');
// manually convert `arrayLikeClasses` property assignments because
// Closure Compiler errors trying to minify them
source = source.replace(/(arrayLikeClasses =)[\s\S]+?= *true/,
"$1{'[object Arguments]': true, '[object Array]': true, '[object Boolean]': false, " +
"'[object Date]': false, '[object Function]': false, '[object Number]': false, " +
"'[object Object]': false, '[object RegExp]': false, '[object String]': true }"
);
// manually convert `cloneableClasses` property assignments because
// Closure Compiler errors trying to minify them
source = source.replace(/(cloneableClasses =)[\s\S]+?= *true/,
"$1{'[object Arguments]': false, '[object Array]': true, '[object Boolean]': true, " +
"'[object Date]': true, '[object Function]': false, '[object Number]': true, " +
"'[object Object]': true, '[object RegExp]': true, '[object String]': true }"
);
// add brackets to whitelisted properties so Closure Compiler won't mung them
// http://code.google.com/closure/compiler/docs/api-tutorial3.html#export
source = source.replace(RegExp('\\.(' + propWhitelist.join('|') + ')\\b', 'g'), "['$1']");
// remove brackets from `_.escape()` in `_.template`
source = source.replace(/__e *= *_\['escape']/g, '__e=_.escape');
// remove brackets from `collection.indexOf` in `_.contains`
source = source.replace("collection['indexOf'](target)", 'collection.indexOf(target)');
// remove brackets from `result[length].value` in `_.sortBy`
source = source.replace("result[length]['value']", 'result[length].value');
// remove whitespace from string literals
source = source.replace(/'(?:(?=(\\?))\1.)*?'/g, function(string) {
// avoids removing the '\n' of the `stringEscapes` object
return string.replace(/\[object |else if|function | in |return\s+[\w']|throw |typeof |use strict|var |@ |'\\n'|\\\\n|\\n|\s+/g, function(match) {
return match == false || match == '\\n' ? '' : match;
});
});
// remove whitespace from `_.template` related regexes
source = source.replace(/(?:reDelimiterCode\w+|reEmptyString\w+|reInsertVariable) *=.+/g, function(match) {
return match.replace(/ |\\n/g, '');
});
// remove newline from double-quoted strings in `_.template`
source = source
.replace('"\';\\n__with ("', '"\';__with("')
.replace('"\\n}__\\n__p += \'"', '"}____p+=\'"')
.replace('"__p = \'"', '"__p=\'"')
.replace('"\';\\n"', '"\';"')
.replace("') {\\n'", "'){'")
// remove `useSourceURL` variable
source = source.replace(/(?:\n +\/\*[^*]*\*+(?:[^\/][^*]*\*+)*\/)?\n *try *\{(?:\s*\/\/.*)*\n *var useSourceURL[\s\S]+?catch[^}]+}\n/, '');
// remove debug sourceURL use in `_.template`
source = source.replace(/(?:\s*\/\/.*\n)* *if *\(useSourceURL[^}]+}/, '');
// minify internal properties used by 'compareAscending', `_.clone`, `_.merge`, and `_.sortBy`
(function() {
var properties = ['criteria', 'index', 'source', 'value'],
snippets = source.match(/( +)(?:function clone|function compareAscending|var merge|var sortBy)\b[\s\S]+?\n\1}/g);
if (!snippets) {
return;
}
snippets.forEach(function(snippet) {
var modified = snippet,
isCompilable = /(?:var merge|var sortBy)\b/.test(modified),
isInlined = !/\bcreateIterator\b/.test(modified);
// minify properties
properties.forEach(function(property, index) {
var reBracketProp = RegExp("\\['(" + property + ")'\\]", 'g'),
reDotProp = RegExp('\\.' + property + '\\b', 'g'),
rePropColon = RegExp("(')?\\b" + property + "\\1 *:", 'g');
if (isCompilable) {
// add quotes around properties in the inlined `_.merge` and `_.sortBy`
// of the mobile build so Closure Compiler won't mung them
if (isInlined) {
modified = modified
.replace(reBracketProp, "['" + minNames[index] + "']")
.replace(reDotProp, "['" + minNames[index] + "']")
.replace(rePropColon, "'" + minNames[index] + "':");
}
else {
modified = modified
.replace(reBracketProp, '.' + minNames[index])
.replace(reDotProp, '.' + minNames[index])
.replace(rePropColon, minNames[index] + ':');
}
}
else {
modified = modified
.replace(reBracketProp, "['" + minNames[index] + "']")
.replace(reDotProp, '.' + minNames[index])
.replace(rePropColon, "'" + minNames[index] + "':")
// correct `value.source` in regexp branch of `_.clone`
if (property == 'source') {
modified = modified.replace("value['" + minNames[index] + "']", "value['source']");
}
}
});
// replace with modified snippet
source = source.replace(snippet, modified);
});
}());
// minify all compilable snippets
var snippets = source.match(
RegExp([
// match the `iteratorTemplate`
'( +)var iteratorTemplate\\b[\\s\\S]+?\\n\\1}',
// match methods created by `createIterator` calls
'createIterator\\((?:{|[a-zA-Z]+)[\\s\\S]+?\\);\\n',
// match variables storing `createIterator` options
'( +)var [a-zA-Z]+IteratorOptions\\b[\\s\\S]+?\\n\\2}',
// match the the `createIterator` function
'( +)function createIterator\\b[\\s\\S]+?\\n\\3}'
].join('|'), 'g')
);
// exit early if no compilable snippets
if (!snippets) {
return source;
}
snippets.forEach(function(snippet, index) {
var isCreateIterator = /function createIterator\b/.test(snippet),
isIteratorTemplate = /var iteratorTemplate\b/.test(snippet),
modified = snippet;
// add brackets to whitelisted properties so Closure Compiler won't mung them
modified = modified.replace(RegExp('\\.(' + iteratorOptions.join('|') + ')\\b', 'g'), "['$1']");
if (isCreateIterator) {
// replace with modified snippet early and clip snippet to the `factory`
// call so other arguments aren't minified
source = source.replace(snippet, modified);
snippet = modified = modified.replace(/factory\([\s\S]+$/, '');
}
// minify snippet variables / arguments
compiledVars.forEach(function(variable, index) {
// ensure properties in compiled strings aren't minified
modified = modified.replace(RegExp('([^.]\\b)' + variable + '\\b(?!\' *[\\]:])', 'g'), '$1' + minNames[index]);
// correct `typeof x == 'object'`
if (variable == 'object') {
modified = modified.replace(RegExp("(typeof [^']+')" + minNames[index] + "'", 'g'), "$1object'");
}
});
// minify `createIterator` option property names
iteratorOptions.forEach(function(property, index) {
if (isIteratorTemplate) {
// minify property names as interpolated template variables
modified = modified.replace(RegExp('\\b' + property + '\\b', 'g'), minNames[index]);
}
else {
if (property == 'array' || property == 'object') {
// minify "array" and "object" sub property names
modified = modified.replace(RegExp("'" + property + "'( *[\\]:])", 'g'), "'" + minNames[index] + "'$1");
}
else {
// minify property name strings
modified = modified.replace(RegExp("'" + property + "'", 'g'), "'" + minNames[index] + "'");
// minify property names in regexes and accessors
if (isCreateIterator) {
modified = modified.replace(RegExp('([\\.|/])' + property + '\\b' , 'g'), '$1' + minNames[index]);
}
}
}
});
// replace with modified snippet
source = source.replace(snippet, modified);
});
return source;
}
/*--------------------------------------------------------------------------*/
// expose `preprocess`
if (module != require.main) {
module.exports = preprocess;
}
else {
// read the Lo-Dash source file from the first argument if the script
// was invoked directly (e.g. `node pre-compile.js source.js`) and write to
// the same file
(function() {
var source = fs.readFileSync(process.argv[2], 'utf8');
fs.writeFileSync(process.argv[2], preprocess(source), 'utf8');
}());
}
}());