tlTestPlanMetrics TSuite Depth-2 Empty-Plan Null Guard Fix

Issue #583

Fixed: opening lib/results/resultsByTSuite.php?tplan_id=<plan-without-linked-test-cases>&format=0 on PHP 8.3 produced HTTP 500 / zero-byte body:

E_WARNING  Attempt to read property "colDefinition" on null - tlTestPlanMetrics.class.php - Line 3389
PHP Fatal: Uncaught TypeError: array_keys(): Argument #1 ($array) must be of
type array, null given - tlTestPlanMetrics.class.php Line 3403

Root Cause

Exactly the pattern flagged during the #579 review, on the sibling method that was not covered by that fix:

• getStatusTotalsTSuiteDepth2ForRender() calls getStatusTotalsByItemForRender($id,'tsuite',…). For a plan whose builds exist but which has zero linked test cases, that inner method returns [null, staircase] (the null contract documented in #579).
• The depth-2 renderer then dereferenced $rx->colDefinition (:3389) and — because resultsByTSuite.php passes groupByPlatform=1 — array_keys($rx->info) (:3403) without a null check. On PHP 8, reading a property on null is an E_WARNING and array_keys(null) is an uncaught TypeError → fatal.

Note: the build-less empty plan never reaches this code because helperGetExecCounters() throws "Can not work with empty build set" first; the reported path needs at least one build.

The Fix — approach

One minimal guard in lib/functions/tlTestPlanMetrics.class.php, identical in shape to the #579 fix:

// getStatusTotalsTSuiteDepth2ForRender(), right after the list() call
if( is_null($rx) ) {
  return null;
}

Why this shape:

• Returning null matches the method's existing contract — its only caller resultsByTSuite.php:33 already handles it: if(is_null($tsInf) || empty($tsInf->infoL2)) renders the "no test suites defined" report branch.
• An early return is preferred over fabricating an empty render object because every consumer treats null as "nothing to report on".
• Alternatives rejected: always setting $exec['tsuites'] = array() inside the metrics hot path (cosmetic key, wide blast radius), or guarding only the two dereference sites (leaves a half-initialised stdClass flowing into the caller).

Verification

Step	Result
Pre-fix repro on fixture plan (build present, zero linked TCs)	HTTP 500, harness shows exactly the warning + TypeError above
Post-fix same URL	HTTP 200, "There are no Test Suites defined…no report can be created" branch
Positive regression: link one TC under nested suites, reload	full "Metrics by Level 1 & Level 2 Test Suites" table (Top/Child rows, Not Run column)
Sibling screens sharing the inner metrics call (resultsGeneral.php, mainPage.php)	HTTP 200, zero new warnings/events
Event Viewer	no new Error/Warning events from the touched code path

Regression suite: Regression — Issue #583 in tmp/TLU_Test_Cases.md.

Follow-up bug discovered during verification

Filed separately with repro steps, root cause and suggested fix:

• #586 pChart declares only a PHP4-style constructor (function pChart()), which PHP 8 no longer calls implicitly → $this->Picture stays null and every chart screen (topLevelSuitesBarChart etc.) fatals with an imagecolorallocate TypeError even on fully populated plans.

Files changed

• lib/functions/tlTestPlanMetrics.class.php — early null return in getStatusTotalsTSuiteDepth2ForRender() (~3376)

Screenshots