var mapping = require('./_mapping'),
fallbackHolder = require('./placeholder');
/** Built-in value reference. */
var push = Array.prototype.push;
/**
* Creates a function, with an arity of `n`, that invokes `func` with the
* arguments it receives.
*
* @private
* @param {Function} func The function to wrap.
* @param {number} n The arity of the new function.
* @returns {Function} Returns the new function.
*/
function baseArity(func, n) {
return n == 2
? function(a, b) { return func.apply(undefined, arguments); }
: function(a) { return func.apply(undefined, arguments); };
}
/**
* Creates a function that invokes `func`, with up to `n` arguments, ignoring
* any additional arguments.
*
* @private
* @param {Function} func The function to cap arguments for.
* @param {number} n The arity cap.
* @returns {Function} Returns the new function.
*/
function baseAry(func, n) {
return n == 2
? function(a, b) { return func(a, b); }
: function(a) { return func(a); };
}
/**
* Creates a clone of `array`.
*
* @private
* @param {Array} array The array to clone.
* @returns {Array} Returns the cloned array.
*/
function cloneArray(array) {
var length = array ? array.length : 0,
result = Array(length);
while (length--) {
result[length] = array[length];
}
return result;
}
/**
* Creates a function that clones a given object using the assignment `func`.
*
* @private
* @param {Function} func The assignment function.
* @returns {Function} Returns the new cloner function.
*/
function createCloner(func) {
return function(object) {
return func({}, object);
};
}
/**
* A specialized version of `_.spread` which flattens the spread array into
* the arguments of the invoked `func`.
*
* @private
* @param {Function} func The function to spread arguments over.
* @param {number} start The start position of the spread.
* @returns {Function} Returns the new function.
*/
function flatSpread(func, start) {
return function() {
var length = arguments.length,
lastIndex = length - 1,
args = Array(length);
while (length--) {
args[length] = arguments[length];
}
var array = args[start],
otherArgs = args.slice(0, start);
if (array) {
push.apply(otherArgs, array);
}
if (start != lastIndex) {
push.apply(otherArgs, args.slice(start + 1));
}
return func.apply(this, otherArgs);
};
}
/**
* Creates a function that wraps `func` and uses `cloner` to clone the first
* argument it receives.
*
* @private
* @param {Function} func The function to wrap.
* @param {Function} cloner The function to clone arguments.
* @returns {Function} Returns the new immutable function.
*/
function wrapImmutable(func, cloner) {
return function() {
var length = arguments.length;
if (!length) {
return;
}
var args = Array(length);
while (length--) {
args[length] = arguments[length];
}
var result = args[0] = cloner.apply(undefined, args);
func.apply(undefined, args);
return result;
};
}
/**
* The base implementation of `convert` which accepts a `util` object of methods
* required to perform conversions.
*
* @param {Object} util The util object.
* @param {string} name The name of the function to convert.
* @param {Function} func The function to convert.
* @param {Object} [options] The options object.
* @param {boolean} [options.cap=true] Specify capping iteratee arguments.
* @param {boolean} [options.curry=true] Specify currying.
* @param {boolean} [options.fixed=true] Specify fixed arity.
* @param {boolean} [options.immutable=true] Specify immutable operations.
* @param {boolean} [options.rearg=true] Specify rearranging arguments.
* @returns {Function|Object} Returns the converted function or object.
*/
function baseConvert(util, name, func, options) {
var setPlaceholder,
isLib = typeof name == 'function',
isObj = name === Object(name);
if (isObj) {
options = func;
func = name;
name = undefined;
}
if (func == null) {
throw new TypeError;
}
options || (options = {});
var config = {
'cap': 'cap' in options ? options.cap : true,
'curry': 'curry' in options ? options.curry : true,
'fixed': 'fixed' in options ? options.fixed : true,
'immutable': 'immutable' in options ? options.immutable : true,
'rearg': 'rearg' in options ? options.rearg : true
};
var forceCurry = ('curry' in options) && options.curry,
forceFixed = ('fixed' in options) && options.fixed,
forceRearg = ('rearg' in options) && options.rearg,
placeholder = isLib ? func : fallbackHolder,
pristine = isLib ? func.runInContext() : undefined;
var helpers = isLib ? func : {
'ary': util.ary,
'assign': util.assign,
'clone': util.clone,
'curry': util.curry,
'forEach': util.forEach,
'isArray': util.isArray,
'isFunction': util.isFunction,
'iteratee': util.iteratee,
'keys': util.keys,
'rearg': util.rearg,
'toInteger': util.toInteger,
'toPath': util.toPath
};
var ary = helpers.ary,
assign = helpers.assign,
clone = helpers.clone,
curry = helpers.curry,
each = helpers.forEach,
isArray = helpers.isArray,
isFunction = helpers.isFunction,
keys = helpers.keys,
rearg = helpers.rearg,
toInteger = helpers.toInteger,
toPath = helpers.toPath;
var aryMethodKeys = keys(mapping.aryMethod);
var wrappers = {
'castArray': function(castArray) {
return function() {
var value = arguments[0];
return isArray(value)
? castArray(cloneArray(value))
: castArray.apply(undefined, arguments);
};
},
'iteratee': function(iteratee) {
return function() {
var func = arguments[0],
arity = arguments[1],
result = iteratee(func, arity),
length = result.length;
if (config.cap && typeof arity == 'number') {
arity = arity > 2 ? (arity - 2) : 1;
return (length && length <= arity) ? result : baseAry(result, arity);
}
return result;
};
},
'mixin': function(mixin) {
return function(source) {
var func = this;
if (!isFunction(func)) {
return mixin(func, Object(source));
}
var pairs = [];
each(keys(source), function(key) {
if (isFunction(source[key])) {
pairs.push([key, func.prototype[key]]);
}
});
mixin(func, Object(source));
each(pairs, function(pair) {
var value = pair[1];
if (isFunction(value)) {
func.prototype[pair[0]] = value;
} else {
delete func.prototype[pair[0]];
}
});
return func;
};
},
'nthArg': function(nthArg) {
return function(n) {
var arity = n < 0 ? 1 : (toInteger(n) + 1);
return curry(nthArg(n), arity);
};
},
'rearg': function(rearg) {
return function(func, indexes) {
var arity = indexes ? indexes.length : 0;
return curry(rearg(func, indexes), arity);
};
},
'runInContext': function(runInContext) {
return function(context) {
return baseConvert(util, runInContext(context), options);
};
}
};
/*--------------------------------------------------------------------------*/
/**
* Casts `func` to a function with an arity capped iteratee if needed.
*
* @private
* @param {string} name The name of the function to inspect.
* @param {Function} func The function to inspect.
* @returns {Function} Returns the cast function.
*/
function castCap(name, func) {
if (config.cap) {
var indexes = mapping.iterateeRearg[name];
if (indexes) {
return iterateeRearg(func, indexes);
}
var n = !isLib && mapping.iterateeAry[name];
if (n) {
return iterateeAry(func, n);
}
}
return func;
}
/**
* Casts `func` to a curried function if needed.
*
* @private
* @param {string} name The name of the function to inspect.
* @param {Function} func The function to inspect.
* @param {number} n The arity of `func`.
* @returns {Function} Returns the cast function.
*/
function castCurry(name, func, n) {
return (forceCurry || (config.curry && n > 1))
? curry(func, n)
: func;
}
/**
* Casts `func` to a fixed arity function if needed.
*
* @private
* @param {string} name The name of the function to inspect.
* @param {Function} func The function to inspect.
* @param {number} n The arity cap.
* @returns {Function} Returns the cast function.
*/
function castFixed(name, func, n) {
if (config.fixed && (forceFixed || !mapping.skipFixed[name])) {
var data = mapping.methodSpread[name],
start = data && data.start;
return start === undefined ? ary(func, n) : flatSpread(func, start);
}
return func;
}
/**
* Casts `func` to an rearged function if needed.
*
* @private
* @param {string} name The name of the function to inspect.
* @param {Function} func The function to inspect.
* @param {number} n The arity of `func`.
* @returns {Function} Returns the cast function.
*/
function castRearg(name, func, n) {
return (config.rearg && n > 1 && (forceRearg || !mapping.skipRearg[name]))
? rearg(func, mapping.methodRearg[name] || mapping.aryRearg[n])
: func;
}
/**
* Creates a clone of `object` by `path`.
*
* @private
* @param {Object} object The object to clone.
* @param {Array|string} path The path to clone by.
* @returns {Object} Returns the cloned object.
*/
function cloneByPath(object, path) {
path = toPath(path);
var index = -1,
length = path.length,
lastIndex = length - 1,
result = clone(Object(object)),
nested = result;
while (nested != null && ++index < length) {
var key = path[index],
value = nested[key];
if (value != null) {
nested[path[index]] = clone(index == lastIndex ? value : Object(value));
}
nested = nested[key];
}
return result;
}
/**
* Converts `lodash` to an immutable auto-curried iteratee-first data-last
* version with conversion `options` applied.
*
* @param {Object} [options] The options object. See `baseConvert` for more details.
* @returns {Function} Returns the converted `lodash`.
*/
function convertLib(options) {
return _.runInContext.convert(options)(undefined);
}
/**
* Create a converter function for `func` of `name`.
*
* @param {string} name The name of the function to convert.
* @param {Function} func The function to convert.
* @returns {Function} Returns the new converter function.
*/
function createConverter(name, func) {
var realName = mapping.aliasToReal[name] || name,
methodName = mapping.remap[realName] || realName,
oldOptions = options;
return function(options) {
var newUtil = isLib ? pristine : helpers,
newFunc = isLib ? pristine[methodName] : func,
newOptions = assign(assign({}, oldOptions), options);
return baseConvert(newUtil, realName, newFunc, newOptions);
};
}
/**
* Creates a function that wraps `func` to invoke its iteratee, with up to `n`
* arguments, ignoring any additional arguments.
*
* @private
* @param {Function} func The function to cap iteratee arguments for.
* @param {number} n The arity cap.
* @returns {Function} Returns the new function.
*/
function iterateeAry(func, n) {
return overArg(func, function(func) {
return typeof func == 'function' ? baseAry(func, n) : func;
});
}
/**
* Creates a function that wraps `func` to invoke its iteratee with arguments
* arranged according to the specified `indexes` where the argument value at
* the first index is provided as the first argument, the argument value at
* the second index is provided as the second argument, and so on.
*
* @private
* @param {Function} func The function to rearrange iteratee arguments for.
* @param {number[]} indexes The arranged argument indexes.
* @returns {Function} Returns the new function.
*/
function iterateeRearg(func, indexes) {
return overArg(func, function(func) {
var n = indexes.length;
return baseArity(rearg(baseAry(func, n), indexes), n);
});
}
/**
* Creates a function that invokes `func` with its first argument transformed.
*
* @private
* @param {Function} func The function to wrap.
* @param {Function} transform The argument transform.
* @returns {Function} Returns the new function.
*/
function overArg(func, transform) {
return function() {
var length = arguments.length;
if (!length) {
return func();
}
var args = Array(length);
while (length--) {
args[length] = arguments[length];
}
var index = config.rearg ? 0 : (length - 1);
args[index] = transform(args[index]);
return func.apply(undefined, args);
};
}
/**
* Creates a function that wraps `func` and applys the conversions
* rules by `name`.
*
* @private
* @param {string} name The name of the function to wrap.
* @param {Function} func The function to wrap.
* @returns {Function} Returns the converted function.
*/
function wrap(name, func) {
var result,
realName = mapping.aliasToReal[name] || name,
wrapped = func,
wrapper = wrappers[realName];
if (wrapper) {
wrapped = wrapper(func);
}
else if (config.immutable) {
if (mapping.mutate.array[realName]) {
wrapped = wrapImmutable(func, cloneArray);
}
else if (mapping.mutate.object[realName]) {
wrapped = wrapImmutable(func, createCloner(func));
}
else if (mapping.mutate.set[realName]) {
wrapped = wrapImmutable(func, cloneByPath);
}
}
each(aryMethodKeys, function(aryKey) {
each(mapping.aryMethod[aryKey], function(otherName) {
if (realName == otherName) {
var data = mapping.methodSpread[realName],
afterRearg = data && data.afterRearg;
result = afterRearg
? castFixed(realName, castRearg(realName, wrapped, aryKey), aryKey)
: castRearg(realName, castFixed(realName, wrapped, aryKey), aryKey);
result = castCap(realName, result);
result = castCurry(realName, result, aryKey);
return false;
}
});
return !result;
});
result || (result = wrapped);
if (result == func) {
result = forceCurry ? curry(result, 1) : function() {
return func.apply(this, arguments);
};
}
result.convert = createConverter(realName, func);
if (mapping.placeholder[realName]) {
setPlaceholder = true;
result.placeholder = func.placeholder = placeholder;
}
return result;
}
/*--------------------------------------------------------------------------*/
if (!isObj) {
return wrap(name, func);
}
var _ = func;
// Convert methods by ary cap.
var pairs = [];
each(aryMethodKeys, function(aryKey) {
each(mapping.aryMethod[aryKey], function(key) {
var func = _[mapping.remap[key] || key];
if (func) {
pairs.push([key, wrap(key, func)]);
}
});
});
// Convert remaining methods.
each(keys(_), function(key) {
var func = _[key];
if (typeof func == 'function') {
var length = pairs.length;
while (length--) {
if (pairs[length][0] == key) {
return;
}
}
func.convert = createConverter(key, func);
pairs.push([key, func]);
}
});
// Assign to `_` leaving `_.prototype` unchanged to allow chaining.
each(pairs, function(pair) {
_[pair[0]] = pair[1];
});
_.convert = convertLib;
if (setPlaceholder) {
_.placeholder = placeholder;
}
// Assign aliases.
each(keys(_), function(key) {
each(mapping.realToAlias[key] || [], function(alias) {
_[alias] = _[key];
});
});
return _;
}
module.exports = baseConvert;
