IDC: preserve re-validation parameters

[bindlegirl]

The new re-validation logic for IDC introduced two new parameters in the IDC error array that define the last checked timestamp and the progressive delay for the next validation attempt. This PR adds logic that makes sure these two parameters are inherited when a new IDC error is generated (by a new remote request).

Closes CONNECT-139

Proposed changes:

• If the core reason for IDC is still valid (wpcom URLs don't match, we rewrite the existing error but keep the delay and timing parameters.
• The timing gets updated if the wpcom URLs are the same in the new error as they are in the existing one but the delay stays the same.

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[github-actions]

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Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/packages/connection/src/identity-crisis/class-identity-crisis.php	282/394 (71.57%)	1.30%	2 ❤️‍🩹

Full summary · PHP report · JS report

[Copilot]

Pull request overview

This PR introduces logic to preserve the re-validation timing parameters (last_checked and next_check_delay) when a new IDC (Identity Crisis) error is generated from a remote request. The changes ensure that if the underlying cause of the IDC remains the same (matching wpcom URLs), the backoff delay is preserved while the timestamp is updated. If the wpcom URLs differ, both timing parameters are reset to initial values.

Changes:

• Updated check_response_for_idc() to preserve timing parameters when wpcom URLs match
• Added has_same_wpcom_urls() helper method to compare wpcom URLs between existing and new IDC errors
• Added comprehensive test coverage for the new timing preservation logic

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
projects/packages/connection/src/identity-crisis/class-identity-crisis.php	Implements logic to preserve next_check_delay when same wpcom URLs are detected, and resets timing when URLs differ
projects/packages/connection/tests/php/identity-crisis/Identity_Crisis_Test.php	Adds four test methods covering preservation, reset, and initial setting of timing parameters
projects/packages/connection/changelog/update-idc-preserve-revalidation-params	Adds changelog entry for the feature

[fgiannar]

Approving after our Slack convo: p1768559411003029-slack-C05PV073SG3 👍

@sergeymitr If you could also take a look at this one before we merge I'd appreciate it.

[sergeymitr]

The code looks good to me, just a small improvement we might want to do.
If the site is messed up enough to trigger this code, it won't hurt to do additional checks.

[sergeymitr]

We might want to check that the value is a valid in case it gets corrupted: a number, and between IDC_VALIDATION_INITIAL_DELAY and IDC_VALIDATION_MAX_DELAY.

[bindlegirl]

Good suggestion. I added the validation and refactored the code a bit for clarity.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

[sergeymitr]

Tested using some in-code hacks, works well 👍