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Riven/riven/srcgen/node_modules/stealthy-require/lib/index.js

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'use strict';
var isNative = /\.node$/;
function forEach(obj, callback) {
for ( var key in obj ) {
if (!Object.prototype.hasOwnProperty.call(obj, key)) {
continue;
}
callback(key);
}
}
function assign(target, source) {
forEach(source, function (key) {
target[key] = source[key];
});
return target;
}
function clearCache(requireCache) {
forEach(requireCache, function (resolvedPath) {
if (!isNative.test(resolvedPath)) {
delete requireCache[resolvedPath];
}
});
}
module.exports = function (requireCache, callback, callbackForModulesToKeep, module) {
var originalCache = assign({}, requireCache);
clearCache(requireCache);
if (callbackForModulesToKeep) {
var originalModuleChildren = module.children ? module.children.slice() : false; // Creates a shallow copy of module.children
callbackForModulesToKeep();
// Lists the cache entries made by callbackForModulesToKeep()
var modulesToKeep = [];
forEach(requireCache, function (key) {
modulesToKeep.push(key);
});
// Discards the modules required in callbackForModulesToKeep()
clearCache(requireCache);
if (module.children) { // Only true for node.js
module.children = originalModuleChildren; // Removes last references to modules required in callbackForModulesToKeep() -> No memory leak
}
// Takes the cache entries of the original cache in case the modules where required before
for ( var i = 0; i < modulesToKeep.length; i+=1 ) {
if (originalCache[modulesToKeep[i]]) {
requireCache[modulesToKeep[i]] = originalCache[modulesToKeep[i]];
}
}
}
var freshModule = callback();
var stealthCache = callbackForModulesToKeep ? assign({}, requireCache) : false;
clearCache(requireCache);
if (callbackForModulesToKeep) {
// In case modules to keep were required inside the stealthy require for the first time, copy them to the restored cache
for ( var k = 0; k < modulesToKeep.length; k+=1 ) {
if (stealthCache[modulesToKeep[k]]) {
requireCache[modulesToKeep[k]] = stealthCache[modulesToKeep[k]];
}
}
}
assign(requireCache, originalCache);
return freshModule;
};