FA-96629 / Phone number formatting / Member archive

SMS sender identifier classifier: overlong alphanumeric senders are accepted · case 04

A twelve-character sender is accepted.

Member previewVariant 4 · 3 implementations · 14 checks per implementation

Case contract

Strip. "+" followed by 8..15 digits is a long code (else invalid). All digits: 3..6 is a short code, 8..15 is a long code rendered with a leading "+", anything else invalid. Otherwise 1..11 characters of letters, digits, space, hyphen or dot with at least one letter is an alphanumeric sender. Return [kind, value].

Why this case matters

Sender identifiers are normalized before messages are queued; a misclassified sender is rejected by the carrier or impersonates another sender.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
twelve-character sender	`["alpha", "FAKECOSHOPS4"]`	`["invalid", "FAKECOSHOPS4"]`	Failed

MEMBER ARCHIVE

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