diff options
Diffstat (limited to 'deps/npm/node_modules/readable-stream/node_modules/unreachable-branch-transform/node_modules/recast/node_modules/private/private.js')
-rw-r--r-- | deps/npm/node_modules/readable-stream/node_modules/unreachable-branch-transform/node_modules/recast/node_modules/private/private.js | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/deps/npm/node_modules/readable-stream/node_modules/unreachable-branch-transform/node_modules/recast/node_modules/private/private.js b/deps/npm/node_modules/readable-stream/node_modules/unreachable-branch-transform/node_modules/recast/node_modules/private/private.js new file mode 100644 index 0000000000..20bed57eeb --- /dev/null +++ b/deps/npm/node_modules/readable-stream/node_modules/unreachable-branch-transform/node_modules/recast/node_modules/private/private.js @@ -0,0 +1,129 @@ +"use strict"; + +var originalObject = Object; +var originalDefProp = Object.defineProperty; +var originalCreate = Object.create; + +function defProp(obj, name, value) { + if (originalDefProp) try { + originalDefProp.call(originalObject, obj, name, { value: value }); + } catch (definePropertyIsBrokenInIE8) { + obj[name] = value; + } else { + obj[name] = value; + } +} + +// For functions that will be invoked using .call or .apply, we need to +// define those methods on the function objects themselves, rather than +// inheriting them from Function.prototype, so that a malicious or clumsy +// third party cannot interfere with the functionality of this module by +// redefining Function.prototype.call or .apply. +function makeSafeToCall(fun) { + if (fun) { + defProp(fun, "call", fun.call); + defProp(fun, "apply", fun.apply); + } + return fun; +} + +makeSafeToCall(originalDefProp); +makeSafeToCall(originalCreate); + +var hasOwn = makeSafeToCall(Object.prototype.hasOwnProperty); +var numToStr = makeSafeToCall(Number.prototype.toString); +var strSlice = makeSafeToCall(String.prototype.slice); + +var cloner = function(){}; +function create(prototype) { + if (originalCreate) { + return originalCreate.call(originalObject, prototype); + } + cloner.prototype = prototype || null; + return new cloner; +} + +var rand = Math.random; +var uniqueKeys = create(null); + +function makeUniqueKey() { + // Collisions are highly unlikely, but this module is in the business of + // making guarantees rather than safe bets. + do var uniqueKey = internString(strSlice.call(numToStr.call(rand(), 36), 2)); + while (hasOwn.call(uniqueKeys, uniqueKey)); + return uniqueKeys[uniqueKey] = uniqueKey; +} + +function internString(str) { + var obj = {}; + obj[str] = true; + return Object.keys(obj)[0]; +} + +// External users might find this function useful, but it is not necessary +// for the typical use of this module. +defProp(exports, "makeUniqueKey", makeUniqueKey); + +// Object.getOwnPropertyNames is the only way to enumerate non-enumerable +// properties, so if we wrap it to ignore our secret keys, there should be +// no way (except guessing) to access those properties. +var originalGetOPNs = Object.getOwnPropertyNames; +Object.getOwnPropertyNames = function getOwnPropertyNames(object) { + for (var names = originalGetOPNs(object), + src = 0, + dst = 0, + len = names.length; + src < len; + ++src) { + if (!hasOwn.call(uniqueKeys, names[src])) { + if (src > dst) { + names[dst] = names[src]; + } + ++dst; + } + } + names.length = dst; + return names; +}; + +function defaultCreatorFn(object) { + return create(null); +} + +function makeAccessor(secretCreatorFn) { + var brand = makeUniqueKey(); + var passkey = create(null); + + secretCreatorFn = secretCreatorFn || defaultCreatorFn; + + function register(object) { + var secret; // Created lazily. + + function vault(key, forget) { + // Only code that has access to the passkey can retrieve (or forget) + // the secret object. + if (key === passkey) { + return forget + ? secret = null + : secret || (secret = secretCreatorFn(object)); + } + } + + defProp(object, brand, vault); + } + + function accessor(object) { + if (!hasOwn.call(object, brand)) + register(object); + return object[brand](passkey); + } + + accessor.forget = function(object) { + if (hasOwn.call(object, brand)) + object[brand](passkey, true); + }; + + return accessor; +} + +defProp(exports, "makeAccessor", makeAccessor); |