fix: support punycode TLDs in URL regex

[HardAndHeavy]

Issue ticket number and link

No related issue — this is a small self-contained fix.

Documentation

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• Documentation is not needed for this change (explain why)

Internal regex fix in URL validation — no user-facing behavior or API changes, so documentation update is not required.

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Summary

Update the URL validation regex to support internationalized domain names (IDN) in Punycode format.

Problem

The current regex rejects valid IDN TLDs because the TLD part only allows letters:

(([a-z\d]([a-z\d-]*[a-z\d])*)\.)+[a-z]{2,}
//                              ^^^^^^^^
//                      only letters allowed

As a result, URLs with Punycode TLDs fail validation, even though they are perfectly valid. Examples of such TLDs:

• .xn--p1ai
• .xn--fiqs8s
• .xn--qxam
• .xn--mgba3a4f16a

Solution

Split the TLD matching into two cases:

• Regular TLDs: letters only, 2+ chars (e.g. .com, .org, .net)
• Punycode TLDs: xn-- prefix followed by letters, digits and hyphens (e.g. .xn--p1ai, .xn--fiqs8s)

(([a-z\d]([a-z\d-]*[a-z\d])*)\.)+([a-z]{2,}|xn--[a-z\d-]+)

Test cases

URL	Before	After
https://example.com	✅	✅
https://example.org	✅	✅
https://example.xn--p1ai	❌	✅
https://example.xn--fiqs8s	❌	✅
https://xn--80adjurfhd.xn--c1aao5a.xn--p1ai	❌	✅
http://localhost:3000	✅	✅
https://192.168.0.1/path	✅	✅

Notes

• Backwards compatible: all previously valid URLs remain valid.
• The fix is generic and covers all IDN TLDs that follow the Punycode encoding standard (RFC 3492), not just specific ones.
• For production-grade TLD validation, consider using a dedicated library (e.g. tldts) with the Public Suffix List, since the set of TLDs changes over time.

Summary by CodeRabbit

• Bug Fixes
  • Improved URL validation to support internationalized domain names by accepting Punycode-form domains (e.g., xn--...). This enhances compatibility with global domain names and reduces false negatives when entering non-ASCII domains.
  • No changes to public interfaces or exported behavior visible to users.

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: aa781817-c617-41dc-99fc-e1927e392630

📥 Commits

Reviewing files that changed from the base of the PR and between a62e3f2 and 7cf2360.

📒 Files selected for processing (1)

• src/utils/helpers.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• src/utils/helpers.ts

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📝 Walkthrough

Walkthrough

Updated isValidUrl URL-validation regex in src/utils/helpers.ts to accept Internationalized Domain Names in Punycode form by allowing xn--... TLDs alongside standard ASCII TLDs. No API changes.

Changes

Punycode Domain Support

Layer / File(s)	Summary
URL validation regex for Punycode TLDs src/utils/helpers.ts	The domain/TLD pattern in the isValidUrl regex is expanded to match Punycode TLDs (xn--[a-z\d](?:[a-z\d-]*[a-z\d])?)) alongside standard ASCII TLDs ([a-z]{2,}).

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~5 minutes

Poem

🐰 I hopped through patterns, thread by thread,
Found xn-- and nodded my head.
Punycode petals in the net's bouquet,
Now names from far can come and play.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically summarizes the main change: adding support for Punycode TLDs in the URL validation regex.
Description check	✅ Passed	The description follows the template with all required sections completed: issue reference, documentation selection with explanation, and comprehensive details on the problem, solution, and test cases.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/utils/helpers.ts`:
- Line 133: The punycode TLD branch in the hostname regex uses the
too-permissive fragment "xn--[a-z\\d-]+", which allows labels ending with a
hyphen; update that fragment to enforce the same edge constraints as regular
labels by replacing it with "xn--[a-z\\d]([a-z\\d-]*[a-z\\d])?" so the punycode
label cannot start or end with a hyphen (refer to the existing label pattern
([a-z\\d]([a-z\\d-]*[a-z\\d])*) to mirror its behavior).

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: da7fb532-2206-4e6a-be2f-9eedf30684ab

📥 Commits

Reviewing files that changed from the base of the PR and between 1d8d32d and a62e3f2.

📒 Files selected for processing (1)

• src/utils/helpers.ts