Update browser not supported message

[panzarino]

• Closes Display accurate error message when browser is not supported #6979

User facing changelog

Updates the error message when a browser is not found or not supported

Additional details

The current message isn't very clear when it comes to unsupported browsers. For example, it can be confusing to see that Cypress cannot find Safari when in reality Safari is just not supported.

How has the user experience changed?

Previous error message cypress run:

> npx cypress run --browser  "safari"

Can't run because you've entered an invalid browser name.

Browser: 'safari' was not found on your system.

Available browsers found are: chrome, firefox, electron

New error message cypress run:

> npx cypress run --browser  "safari"

Can't run because you've entered an invalid browser name.

Browser: 'safari' was not found on your system or is not supported by Cypress.

Cypress supports the following browsers:
- chrome
- chromium
- edge
- electron
- firefox (Cypress support in beta)

You can also use a custom browser: https://on.cypress.io/launching-browsers#Customize-available-browsers

Available browsers found are:
- chrome
- firefox
- electron

Previous error message cypress open:

New error message cypress open:

PR Tasks

• Have tests been added/updated?
• Has the original issue been tagged with a release in ZenHub?

[cypress-bot]

Thanks for the contribution! Below are some guidelines Cypress uses when doing PR reviews.

• Please write [WIP] in the title of your Pull Request if your PR is not ready for review - someone will review your PR as soon as the [WIP] is removed.
• Please familiarize yourself with the PR Review Checklist and feel free to make updates on your PR based on these guidelines.

PR Review Checklist

If any of the following requirements can't be met, leave a comment in the review selecting 'Request changes', otherwise 'Approve'.

User Experience

• The feature/bugfix is self-documenting from within the product.
• The change provides the end user with a way to fix their problem (no dead ends).

Functionality

• The code works and performs its intended function with the correct logic.
• Performance has been factored in (for example, the code cleans up after itself to not cause memory leaks).
• The code guards against edge cases and invalid input and has tests to cover it.

Maintainability

• The code is readable (too many nested 'if's are a bad sign).
• Names used for variables, methods, etc, clearly describe their function.
• The code is easy to understood and there are relevant comments explaining.
• New algorithms are documented in the code with link(s) to external docs (flowcharts, w3c, chrome, firefox).
• There are comments containing link(s) to the addressed issue (in tests and code).

Quality

• The change does not reimplement code.
• There's not a module from the ecosystem that should be used instead.
• There is no redundant or duplicate code.
• There are no irrelevant comments left in the code.
• Tests are testing the code’s intended functionality in the best way possible.

Internal

• The original issue has been tagged with a release in ZenHub.

[cypress]

---

Test summary

3575 • 0 • 54 • 0

---

Run details

Project	cypress
Status	Passed
Commit	510d5dc
Started	May 28, 2020 6:50 PM
Ended	May 28, 2020 6:57 PM
Duration	06:14 💡
OS	Linux Debian - 10.1
Browser	Firefox 74

View run in Cypress Dashboard ➡️

---

This comment has been generated by cypress-bot as a result of this project's GitHub integration settings. You can manage this integration in this project's settings in the Cypress Dashboard

[flotwig]

nice! this should help make things clearer

[jennifer-shehane]

Pending release of https://github.com/cypress-io/cypress-services/pull/2601 where this link should work: https://on.cypress.io/customize-browsers