spy-lit-issue
demo a potential issue with lit-element/html and sinon.spy
yarn install
yarn test
The /src/my-element.test.js file shows two tests that are identical, expect the event handlers in /src/my-element.js are setup in different ways.
the #button1 event handler uses mechanisms within lit-html(or lit-element?) to magically bind the event handler and perform optimizations. The test for this button fails.
the #button2 event handler is bound manually. The test for this button passes.