Bugfix Issue 1011 NoContext getTestCasePrefix EmptyId

Issue #1011 — login as user without any test-project context logs SQL error + PHP warnings (getTestCasePrefix empty id)

Issue: #1011 Commit: abb99067e (fix) Status: VERIFIED-FIXED (2026-09-05)

Symptom

Logging in as a user without any test-project context (role <no rights> on a fresh DB, or any flow that hands testcase::getPrefix() an unresolvable node id) logs two event groups into the events table:

log_level=2  GUI       E_WARNING\nTrying to access array offset on null - in .../lib/functions/testcase.class.php - Line 2172
log_level=1  DATABASE  ERROR ON exec_query() - database.class.php <br />1064 -
            /* Class:testproject - Method: getTestCasePrefix */ SELECT prefix FROM testprojects WHERE id = (empty)

The SQL 1064 then aborts the request with the TestLink "DB Access Error" debug backtrace.

Investigation

Reproduced on a fresh DB with a fixture user noview (id=2, role_id=3 = <no rights>, no project role, only private test project) plus a pure code-level repro that exercises exactly the failing sequence (testcase::getPrefix(null, null) and testcase::getPrefix(99999999, null)). The plain index.php landing of a fresh DB does not fire it because initProject() always commits the first project into the session; the exception is a session/context where the id handed to getPrefix() cannot be resolved to a tree path (empty/forged/nonexistent id, or no project access).

Measured events reproductions are logged in the investigation comment on the issue.

Root cause chain

1. lib/functions/testcase.class.php:2166 — getPrefix($id, $tproject_id = null).
2. When $tproject_id is null: $path2root = $this->tree_manager->get_path($id) — testcase.class.php:2171.
3. tree_manager->get_path() (lib/functions/tree.class.php:408) returns null/[] whenever _get_path() finds no node (tree.class.php:462-475: a node missing from nodes_hierarchy sets $node_list = null).
4. Unconditional $root = $path2root[0]['parent_id'] — testcase.class.php:2172 → PHP 8 E_WARNING "Trying to access array offset on null".
5. $root stays null → $this->tproject_mgr->getTestCasePrefix(null) — testcase.class.php:2174.
6. testproject::getTestCasePrefix($id) (lib/functions/testproject.class.php:998-1004) interpolates raw: WHERE id = {$id} ⇒ WHERE id = ⇒ MySQL 1064, request dies.

Blast radius: every caller that may pass a null id or lack project context — testcaseCommands.class.php:576,619, xmlrpc.class.php:4720, testplan.class.php:647,5868,6778,6860, print.inc.php:2357 (legacy print path), plus internal callers at testcase.class.php:2328,2978,2997,5717,7308. The issue was surfaced by the Test Case Print permission-path testing (Refs #1010).

Fix (minimal, defensive — matches the issue suggestion)

Guard getPrefix() so the empty-tree-path case is handled before any dereference:

$path2root = $this->tree_manager->get_path($id);
// No project context (user without any test-project access) or a
// nonexistent node id: get_path() returns null/empty. Bail out instead
// of indexing $path2root[0] (E_WARNING) and running
// getTestCasePrefix(null) which builds "WHERE id = " (SQL 1064).
if (is_null($path2root) || count($path2root) == 0) {
  return array(null, null);
}
$root = $path2root[0]['parent_id'];

Returning array(null, null) mirrors the pre-existing "project with no prefix" shape (getTestCasePrefix() already returns null for a prefix-less project), and all callers treat a null first element as "no prefix" (they concatenate $pfx[0] . glue . external_id). The fast path ($tproject_id given) and the valid deep-link path (non-empty path) are byte-identical to before.

Why this method (alternatives rejected)

• Not fixing getTestCasePrefix() itself to validate $id: it would mask contract violations call-site by call-site; the abort must happen at the point where the project context is derived, i.e. getPrefix().
• Not forcing a default project: that would silently grant context a user does not have and could diverge from hasRight() outcomes.
• Not a bigger refactor of getPrefix()/path resolution — a targeted null-guard matches the project's established defensive pattern (see tlUser.class.php, navBar.php guards from previous bugfixes).

Verification

• getPrefix(null, null) and getPrefix(99999999, null) → array(NULL, NULL), zero WARNING/ERROR rows in events.
• getPrefix(102, null) (valid deep link, fixture project 100/suite 101/tc 102) → array('FIXTURE', '100') — derivation unchanged.
• getPrefix(102, 100) (fast path) → array('FIXTURE', 100) — unchanged.
• Login as noview (no project context) → landing frameset renders, events shows only INFO AUDIT rows.
• Modern Test Case Print screen as noview (BFF action=tc_print&testcase_id=0) → HTTP 400, no events.
• php -l lib/functions/testcase.class.php passes. No i18n strings touched.
• Event Viewer / events table after all regression runs: no new Error/Warning rows.
• Regression suite TC-1011.1..TC-1011.7 appended to tmp/TLU_Test_Cases.md (7/7 PASS).

Screenshots

Files changed

• lib/functions/testcase.class.php (+9/−0) — empty-tree-path guard in getPrefix().
• tmp/TLU_Test_Cases.md — regression suite TC-1011.* (7/7 PASS, local file).
• docs/screenshots/issue-1011-eventviewer-clean.png — evidence.

Follow-up

• Sureface of the same bug class found during review in dead code: #1016 — formatTestCaseIdentity() references undefined $tc_id and unguarded $path2root[0] (unreachable, filed separately).