Material-ui: [material-icons] Testing

[at-webdev]

I am using React Testing Library, Is it possible to test in specific Material UI icon as ArrowLeft / ArrowRight instead of .MuiSvgIcon-root?

App component:

return {open ? <ArrowLeft/> :<ArrowRight/>}

RTL Testing : Below tests are passing but it doesn't check in specific ArrowLeft or ArrowRight icon.

describes("MockTest",()=>{

it("renders Left arrow",()=>{
const {container} = renders(<App open={true}/>);
expect(container.querySelector(".MuiSvgIcon-root").toBeTruthy();
});

it("renders Right arrow",()=>{
const {container} = renders(<App open={false}/>);
expect(container.querySelector(".MuiSvgIcon-root").toBeTruthy();
});

});

• [x] I have searched the issues of this repository and believe that this is not a duplicate.

[oliviertassinari]

@at-webdev For internal test purposes, we leverage:

https://github.com/mui-org/material-ui/blob/8452e7195ffa2e9f823ea9f44681739b8e33b797/packages/material-ui/src/utils/createSvgIcon.js#L9

However, this attribute is removed once the package is published on npm (to save bundle size and not leak test internals) with:

https://github.com/mui-org/material-ui/blob/8452e7195ffa2e9f823ea9f44681739b8e33b797/babel.config.js#L38

Now, considering we frequently need this in our tests, I would be in favor of making it public with:

diff --git a/packages/material-ui/src/utils/createSvgIcon.js b/packages/material-ui/src/utils/createSvgIcon.js
index 2d146ab87d..5f53ccca28 100644
--- a/packages/material-ui/src/utils/createSvgIcon.js
+++ b/packages/material-ui/src/utils/createSvgIcon.js
@@ -6,7 +6,7 @@ import SvgIcon from '../SvgIcon';
  */
 export default function createSvgIcon(path, displayName) {
   const Component = (props, ref) => (
-    <SvgIcon data-mui-test={`${displayName}Icon`} ref={ref} {...props}>
+    <SvgIcon data-testid={`${displayName}Icon`} ref={ref} {...props}>
       {path}
     </SvgIcon>
   );

@eps1lon What do you think?

[eps1lon]

I think icons are the one case where we could make an exception since they have reasonable user impact and no simple alternative. I just hope we don't have to argue why we ship them for icons but not component X.

I'd consider the bundle size implications negligible. If you've got many icons on your page then either: compression will flatten the curve or you should look at <use>.

And as a little bit of anecdotal cherry on top: facebook ships them in their SSR payload as well and twitter renders them client side.

[jaebradley]

@oliviertassinari do you mind if I try implementing this?

And would you still want to keep the data-mui-test attribute for posterity (even if it gets removed before publication) or would you prefer if it was swapped with data-test-id?

[oliviertassinari]

@jaebradley in the past, we have discussed replacing as many data-mui-test attributes with built-in accessibility features.

Assuming we will keep pushing in this direction, I think that we can rename the prop in SvgIcon and update all the tests that depends on it.

[eps1lon]

I wanted to have a look at existing data-mui-test usage anyway. Hopefully we don't even use them anymore at which point we might as well remove them. Otherwise people might get confused if they look at the source code (not that I wouldn't prefer this to be impossible but that kind of doesn't work with _open_ source :smile: ).