[Theme] Avoid process exit when failing to delete a file from the remote theme

[frandiox]

WHY are these changes introduced?

I found that this promise rejection was causing process exit:

Turning it here into an error message instead:

(Note in the above image I was using renderWarning but I've changed it to renderError since that's more accurate, I think)

WHAT is this pull request doing?

How to test your changes?

Post-release steps

Measuring impact

How do we know this change was effective? Please choose one:

• n/a - this doesn't need measurement, e.g. a linting rule or a bug-fix
• Existing analytics will cater for this addition
• PR includes analytics changes to measure impact

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes

[github-actions]

Thanks for your contribution!

Depending on what you are working on, you may want to request a review from a Shopify team:

• Themes: @shopify/advanced-edits
• UI extensions: @shopify/ui-extensions-cli
  • Checkout UI extensions: @shopify/checkout-ui-extensions-api-stewardship
• Hydrogen: @shopify/hydrogen
• Other: @shopify/app-inner-loop

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟡	Statements	72.61% (+0.01% 🔼)	8522/11737
🟡	Branches	69.54% (+0.02% 🔼)	4178/6008
🟡	Functions	71.61%	2205/3079
🟡	Lines	72.92% (+0.01% 🔼)	8064/11058

Test suite run success

1939 tests passing in 873 suites.

Report generated by 🧪jest coverage report action from df7b178

[karreiro]

Thank you for this PR, @frandiox!

I notice that it works as expected during startup, however, when the server is already running and users remove the templates/gift_card.liquid, they don't get the error message.

I don't consider that a blocker to merge tho, because the goal of this fix is to prevent the process from unexpectedly terminating, but I believe it would be nice if we could show the message in that context as well.

Thanks again for this PR!

[jamesmengo]

🥳 This improves the output for theme push as well! Thank you!

We may be able to improve this even further in a followup issue by doing something like this by adding the delete results to the returned Results in the push command. I have a prototype here. Let me know your thoughts!