fix: Updates unknown state to -1,adds fix for failing test case

Signed-off-by: Sahil Rasaikar <sahil.rasaikar@gmail.com>

rules/alerting.go

@@ -50,6 +50,8 @@ const (
 type AlertState int
 
 const (
+	// StateUnknown is the state of an alert that has not yet been evaluated.
+	StateUnknown AlertState = -1
 	// StateInactive is the state of an alert that is neither firing nor pending.
 	StateInactive AlertState = iota
 	// StatePending is the state of an alert that has been active for less than
@@ -58,8 +60,6 @@ const (
 	// StateFiring is the state of an alert that has been active for longer than
 	// the configured threshold duration.
 	StateFiring
-	// StateUnknown is the state of an alert that has not yet been evaluated.
-	StateUnknown
 )
 
 func (s AlertState) String() string {
@@ -536,13 +536,14 @@ func (r *AlertingRule) Eval(ctx context.Context, queryOffset time.Duration, ts t
 // State returns the maximum state of alert instances for this rule.
 // StateFiring > StatePending > StateInactive > StateUnknown.
 func (r *AlertingRule) State() AlertState {
-	// If the rule has never been evaluated, return StateUnknown
-	if r.GetEvaluationTimestamp().IsZero() {
-		return StateUnknown
-	}
 
 	r.activeMtx.Lock()
 	defer r.activeMtx.Unlock()
+	
+	// Check if the rule has been evaluated
+	if r.evaluationTimestamp.Load().IsZero() {
+		return StateUnknown
+	}
 
 	maxState := StateInactive
 	for _, a := range r.active {

rules/alerting_test.go

@@ -85,6 +85,8 @@ func TestAlertingRuleState(t *testing.T) {
 	for i, test := range tests {
 		rule := NewAlertingRule(test.name, nil, 0, 0, labels.EmptyLabels(), labels.EmptyLabels(), labels.EmptyLabels(), "", true, nil)
 		rule.active = test.active
+		// Set evaluation timestamp to simulate that the rule has been evaluated
+		rule.SetEvaluationTimestamp(time.Now())
 		got := rule.State()
 		require.Equal(t, test.want, got, "test case %d unexpected AlertState, want:%d got:%d", i, test.want, got)
 	}