🐛 Work around incorrect global context in @percy/dom #164
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Robdel12
approved these changes
Feb 4, 2021
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What is this?
The
@percy/dompackage uses a UMD format which assigns exports to aglobalThisvariable when in a browser environment. However, if the implementation ofglobalThisis incorrect (mozilla/geckodriver#1798), thePercyDOMobject is not correctly carried forward into other script executions where the DOM is meant to be serialized.This PR aims to work around this issue by checking if
windowandglobalThisare not equal to each other (which technically should be impossible under normal circumstances). If they are not equal, the library adds itself towindowahead of the eventual UMD dance.While testing this, I also noticed that babel helpers were inlined multiple times. Updating this setting to
bundledwill ensure they are only bundled once in the final output.