Issue: #459 Branch: fix/issue-459 · Commit: a925530f1 (fix, ±1 line) + 6172bd1ac (regression suite) Status: FIXED & VERIFIED (2026-08-24)

The original report claimed the typo was "currently harmless" (found by code reading, not reproduced). Live reproduction disproved the harmless verdict: every FAILED tl.addPlatformToTestPlan / tl.removePlatformFromTestPlan call returns the correct XML-RPC error payload, but ALSO writes a bogus PHP warning into the Event Viewer (events table):

mysql> SELECT id, log_level, description FROM events\G
     log_level: 2
  description: E_WARNING
Undefined variable $tatus_ok - in .../lib/api/xmlrpc/v1/xmlrpc.class.php - Line 7024

Repro (fresh DB, events table verified EMPTY before): set an admin devKey, POST IXR request tl.removePlatformFromTestPlan {devKey:<valid>, testplanid:999999, platformname:"NoSuchPlatform"}. Response = correct error code 3000 ("The Test Plan ID (999999) provided does not exist!") — plus the warning row above.

1. lib/api/xmlrpc/v1/xmlrpc.class.php:6958 — private platformLinkOp($args,$op,$messagePrefix) backs both public methods: tl.addPlatformToTestPlan (:6827) and tl.removePlatformFromTestPlan (:6841).
2. :6964 — $status_ok is the guard variable; error paths set it false at :6982 (unknown platform) and :7012 (unlink blocked by linked TC versions); _runChecks() failures (auth/testplanid) also leave it false.
3. :7020-7022 — success path returns early (if($status_ok) return $ret;).
4. :7024 — if(! $tatus_ok) { return $this->errors; } — $tatus_ok (missing the s) is never assigned anywhere in the tree (verified: exactly one grep hit).
5. Under PHP ≥8 the read raises E_WARNING; TestLink's own handler watchPHPErrors (defined at lib/functions/logger.class.php:1407, registered via set_error_handler at :1483) persists it into events. Control flow was never wrong — when line 7024 is reached $status_ok is always false and !null === true, so the payload stayed correct. The damage is pure event-log pollution on EVERY failure mode of the two methods.

Typo exists in exactly 1 file / 1 line. Callers of platformLinkOp(): the two API methods above ⇒ all their failure modes (auth fail, bad testplanid, missing platformname, unknown platform, unlink blocked by linked test cases). No REST BFF or UI layer reaches this code.

One line at xmlrpc.class.php:7024: $tatus_ok → $status_ok.

Rejected alternatives:

• deleting the final if block entirely (works today but loses the explicit error-return contract and silently breaks if control flow ever changes);
• restructuring into if/else (unnecessary churn for a bug fix).

Regression matrix executed live against http://localhost:8082 with fixtures built through the API itself (project id=1 prefix fx459, plan id=2, platform PlatA, suite id=3, tcversion id=5 linked via testplan_tcversions):

Event Viewer watermark unchanged across the whole post-fix matrix.

• #663: successful unlink of a platform with no linked TC versions writes 2× E_WARNING "Trying to access array offset on null" at line 7008 (countLinkedTCVersionsByPlatform() returns null on empty set).
• #664: createTestProject with omitted/misnamed params writes E_WARNING "Undefined array key" at lines 2230-2231.