Issue 427 — Baselines L1 & L2 report: null $rsu loop guard (no-baseline E_WARNING)

Issue: https://github.com/sebiboga/testlink-upgraded/issues/427 Related: #424 (earlier mitigation on this file), #639 (L18N notices in this screen's XLS export — separate bug)

Symptom

Opening Reports and Metrics → Baselines Level 1 & Level 2 Test Suites for any test plan that has never had a baseline saved wrote an E_WARNING into the events table on every render:

E_WARNING
foreach() argument must be of type array|object, null given - in lib/results/baselinel1l2.php - Line 95

The original issue body reported a worse variant — a fatal Cannot use object of type stdClass as array at compiled-template line 140 ($gui->statistics[$platId]) — plus a second defect where $gui->statistics = array() inside the platform loop reset the accumulator so only the last platform survived. Both of those were already mitigated by run #424 (initialization hoisted above the loop), which is why post-#424 renders returned HTTP 200. What remained was the unguarded loop over a null row map.

Approach

Root cause chain:

1. lib/functions/database.class.php:981 — fetchRowsIntoMap4l() starts with $items = null and only materializes the array inside its row loop; an empty result set returns null (:1004).
2. lib/results/baselinel1l2.php:80 assigns that null to $rsu whenever the plan has zero rows in baseline_l1l2_context × baseline_l1l2_details.
3. lib/results/baselinel1l2.php:95 iterates $rsu unconditionally → PHP 8 E_WARNING, logged per render.

Fix (minimal, single call site):

$rsu = $db->fetchRowsIntoMap4l($sql,$keyCols,true);

// fetchRowsIntoMap4l() returns NULL when the plan has no saved baseline
// yet; iterating null raised "E_WARNING foreach() argument must be of
// type array|object, null given" on every no-baseline render. (#427)
if( is_null($rsu) ) {
  $rsu = array();
}

Alternatives rejected:

• Changing database.class.php return contract (null → array) — ~10 call sites share that fetcher; a contract change could ripple into unrelated reports.
• Wrapping the foreach in is_array() instead — equivalent behavior but the normalization reads cleaner next to the hoisted init from #424.

Commit: 6504fc15b (fix(results): guard baselinel1l2 loop against null $rsu …, branch fix/issue-427).

Verification (regression matrix, run 2026-08-23)

Fixtures: php tmp/fixtures_427.php → project RPT427 / plan Plan427A (id 6, no platforms, no baseline); php tmp/fixtures_427b.php → project RPT427B / plans Plan427B (id 10, platforms P-ONE + P-TWO, baselines on both) and Plan427C (id 11, platform P-ONE only, baseline). Baseline rows carry passed=7 / not_run=3 of total 10 per top→child pair.

Case	Request	Result
R1 no baseline	baselinel1l2.php?tplan_id=6&tproject_id=1&format=0	HTTP 200 header-only report; 0 new Error/Warning events (pre-fix produced E_WARNING events id 3)
R2 two platforms	tplan_id=10&…&format=0	HTTP 200; BOTH Results on Platform: P-ONE and P-TWO metric tables render with 70%/30% percentages — accumulator intact across loop iterations
R3 single platform	tplan_id=11&…&format=0	HTTP 200; single P-ONE section
R4 XLS export	tplan_id=6&…&format=1&spreadsheet=1	HTTP 200 valid .xls download; no fatal on the touched path

Event Viewer after the suite: zero new Error/Warning rows. The export path did surface two pre-existing L18N-level (log_level 32) notices (priority_level, not_run not localized for en_GB) — logged separately as #639, deliberately not fixed in this scope.

Full suite: Suite 427 in tmp/TLU_Test_Cases.md (5/5 PASS).