gristlabs_grist-core/app/client/lib/browserGlobals.js

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/**
* Module that allows client-side code to use browser globals (such as `document` or `Node`) in a
* way that allows those globals to be replaced by mocks in browser-less tests.
*
* E.g. test/client/clientUtil.js can replace globals with those provided by jsdom.
*/
var allGlobals = [];
/* global window */
var globalVars = (typeof window !== 'undefined' ? window : {});
/**
* Usage: to get access to global variables `foo` and `bar`, call:
* var G = require('browserGlobals').get('foo', 'bar');
* and use G.foo and G.bar.
*
* This modules stores a reference to G, so that setGlobals() call can replace the values to which
* G.foo and G.bar refer.
*/
function get(varArgNames) {
var obj = {
neededNames: Array.prototype.slice.call(arguments),
globals: {}
};
updateGlobals(obj);
allGlobals.push(obj);
return obj.globals;
}
exports.get = get;
/**
* Internal helper which updates properties of all globals objects created with get().
*/
function updateGlobals(obj) {
obj.neededNames.forEach(function(key) {
obj.globals[key] = globalVars[key];
});
}
/**
* Replace globals with those from the given object. The previous mapping of global values is
* returned, so that it can be restored later.
*/
function setGlobals(globals) {
var oldVars = globalVars;
globalVars = globals;
allGlobals.forEach(function(obj) {
updateGlobals(obj);
});
return oldVars;
}
exports.setGlobals = setGlobals;