refactor(rpm-rebuild): reduce log verbosity and detect resource failures

- Add analyze_build_failure() to distinguish resource failures from build failures
- Add EXIT trap to guarantee cleanup on timeout/SIGTERM/rlDie
- Execute rpmbuild silently, show only command and result
- Detect patterns: disk full, SIGKILL, missing dependencies

tests/Sanity/rpm-rebuild/main.fmf

@@ -4,7 +4,7 @@ require+:
   - rpm-build
 duration: 1h
 
-adjust:
+adjust+:
   - require+:
     - dnf5-plugins
     when: distro == fedora or distro > rhel-10 or distro > centos-stream-10

tests/Sanity/rpm-rebuild/runtest.sh

@@ -2,10 +2,53 @@
 # vim: dict+=/usr/share/beakerlib/dictionary.vim cpt=.,w,b,u,t,i,k
 . /usr/share/beakerlib/beakerlib.sh || exit 1
 
+# Analyze build failure and determine if it's a resource issue or real failure
+analyze_build_failure() {
+    local logfile="$1"
+    local detected_cause=""
+
+    # Extensible table of known resource failure patterns
+    # Format: "regex_pattern|diagnostic_message"
+    local -a RESOURCE_PATTERNS=(
+        "No space left on device|Disk space exhausted"
+        "signal: 9|Build killed with SIGKILL"
+        "SIGKILL: kill|Build killed with SIGKILL"
+        "Failed build dependencies|Missing build dependencies. Is CRB repo enabled?"
+    )
+
+    # Search for each pattern in the log (first match wins)
+    for pattern_entry in "${RESOURCE_PATTERNS[@]}"; do
+        IFS='|' read -r pattern message <<< "$pattern_entry"
+        if grep -qiE "$pattern" "$logfile"; then
+            detected_cause="$message"
+            break
+        fi
+    done
+
+    # Always show tail of log
+    rlLogInfo "Last 20 lines of build log:"
+    tail -n 20 "$logfile" | while IFS= read -r line; do
+        rlLogInfo "$line"
+    done
+
+    if [[ -n "$detected_cause" ]]; then
+        rlFileSubmit "$logfile"
+        rlDie "Fail reason (likely): $detected_cause"
+        # rlDie aborts here, but trap guarantees cleanup
+    fi
+}
+
 PACKAGE="$(rpm -qf "$(which rustc)")"
 
 rlJournalStart
     rlPhaseStartSetup
+        # Trap for guaranteed cleanup (even with rlDie, TMT timeouts, SIGTERM)
+        cleanup_on_exit() {
+            [[ -n "$TmpDir" && -d "$TmpDir" ]] && rm -rf "$TmpDir"
+            [[ -n "$TOPDIR" && -d "$TOPDIR" ]] && rm -rf "$TOPDIR"
+        }
+        trap cleanup_on_exit EXIT
+
         declare TmpDir
         rlAssertRpm "$PACKAGE" || rlDie "rustc not found. Aborting testcase..."
         rlRun "TmpDir=\$(mktemp -d)" 0 "Creating tmp directory"
@@ -46,13 +89,28 @@ rlJournalStart
         # builddep needs to be run from the srpm, not the spec file, to be able
         # to generate them:
         # https://fedoraproject.org/wiki/Changes/DynamicBuildRequires#rpmbuild
-        rlRun "dnf builddep -y ${SRPM}"
+        rlRun "dnf -q builddep -y ${SRPM}"
     rlPhaseEnd
 
     rlPhaseStartTest
         set -o pipefail
-        rlRun "rpmbuild -bb ${SPECDIR}/${SPECNAME} |& tee ${SRPM}_rpmbuild.log"
-        rlFileSubmit "${SRPM}_rpmbuild.log"
+        LOGFILE="${SRPM}_rpmbuild.log"
+        BUILD_CMD="rpmbuild -bb ${SPECDIR}/${SPECNAME}"
+
+        # Log the command being executed (for visibility in test output)
+        rlLog "Executing: $BUILD_CMD"
+
+        # Execute rpmbuild silently, saving complete log to file
+        if $BUILD_CMD &> "$LOGFILE"; then
+            rlPass "rpmbuild succeeded"
+        else
+            # Analyze cause of failure
+            analyze_build_failure "$LOGFILE"
+            # If analyze_build_failure returns (didn't rlDie), it's a real failure
+            rlFail "rpmbuild failed"
+        fi
+
+        rlFileSubmit "$LOGFILE"
     rlPhaseEnd
 
     rlPhaseStartCleanup