Stepper: Fix navigating to a gated step

[alshakero]

Fixes #98059

Proposed Changes

Stepper currently allows flows to navigate to a gated step while logged out, then it detects your auth status and if you're not logged in, it will redirect you to login. This is a roundabout way to redirect to auth when we have all the information we need before going to the gated step.

This change redirects the user to login before redirecting them to a gated step, without navigating to the gated step at all.

Why are these changes being made?

For a saner tracks narrative.

Testing Instructions

This needs a bit of thorough testing.

In-Stepper auth

1. While incognito,
2. Open DevTools > Network, tick "Preserve log", and filter by calypso_signup_step_start.
3. Go to /setup/onboarding.
4. Skip goals. You should see one more entry of calypso_signup_step_start.
5. Pick a design. You should NOT see one more entry of calypso_signup_step_start.
6. Click Continue. You should see one more entry of calypso_signup_step_start.
7. You should land at the user step. You should see one more entry of calypso_signup_step_start.
8. Sign up using anything, you should end up at /setup/onboarding/domains.
9. Click Browser Back, you should end up at the design step.
10. Pick a design and click Continue.
11. You should land at the user step
12. Click Back from the flow's page top left.
13. You should end up at Pick a theme.

---

1. While incognito,
2. Open DevTools > Network, tick "Preserve log", and filter by calypso_signup_step_start.
3. Go to /setup/onboarding
4. Skip goals. You should see one more entry of calypso_signup_step_start.
5. Pick a design. You should NOT see one more entry of calypso_signup_step_start.
6. Click Continue. You should see one more entry of calypso_signup_step_start.
7. You should land at the user step. Click "Log in".
8. Log in using any method.
9. You should end up at /setup/onboarding/domains.

Legacy auth

This tests auth that uses legacy non-Stepper auth

1. While incognito,
2. Open DevTools > Network, tick "Preserve log", and filter by calypso_signup_step_start.
3. Go to /setup/newsletter.
4. You should see one calypso_signup_step_start.
5. Click "Launch my newsletter".
6. You should land at the user URL (/start/...) and see one more calypso_signup_step_start.
7. Sign up.
8. You should land newsletterSetup page and see one more calypso_signup_step_start.

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129247

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129247&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129247&env=a8c-for-agencies

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

App Entrypoints (~183 bytes added 📈 [gzipped])

name           parsed_size           gzip_size
entry-stepper       +791 B  (+0.0%)     +183 B  (+0.0%)

Common code that is always downloaded and parsed every time the app is loaded, no matter which route is used.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• notifications
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug fix/navigating-to-gated-step on your sandbox.

[alshakero]

@arthur791004 hi! I would really appreciate a review considering you and I are the most familiar with this part.

[MicBosi]

Tested all requested scenarios - everything works as expected.
I don't see any extraneous calypso_signup_step_start being fired.

I also tested pointing the browser directly to /setup/onboarding/user while logged out: fires calypso_signup_step_start {step: domains, skip_step_render: true}, also as expected. Note in this case the goals and design-setup steps are never invoked, after user step we land in domains and proceed from there.

[vykes-mac]

This test well for the described scenarios. It solves a lot of event duplication concerns that are mentioned here. Can we get this merged soon.

[arthur791004]

Oops...I'm in GK this week and didn't notice the ping 🙈

[alshakero]

No worries!