fix(application): caas model application status to respect equivalent…

… severity

When selecting between operator and application statuses with the same severity level (e.g. both
waiting) on a caas model Juju selects the operator status instead of the application status, which
is likely more relevant, as reported by https://bugs.launchpad.net/juju/+bug/2038833/comments/2

Builds on the changes in PR juju#17572

core/status/caas.go

@@ -76,9 +76,10 @@ func ApplicationDisplayStatus(applicationStatus, operatorStatus StatusInfo, expe
 		return operatorStatus
 	}
 
-	// Check if the application status has been set to a higher severity status
-	// than the operator status (e.g. set to maintenance by the charm)
-	if statusSeverities[appStatus] > statusSeverities[opStatus] {
+	// Check if the application status has been set to an equivalent or higher
+	// severity status than the operator status (e.g. set to waiting by the
+	// charm)
+	if statusSeverities[appStatus] >= statusSeverities[opStatus] {
 		return applicationStatus
 	}
 

core/status/caas_test.go

@@ -280,6 +280,18 @@ func (s *UnitCloudStatusSuite) TestApplicatoinOpeartorStatusChoice(c *gc.C) {
 				Status:  status.Waiting,
 				Message: "unit",
 			},
+			expectWorkload: true,
+			messageCheck:   "unit",
+		},
+		{
+			operatorStatus: status.StatusInfo{
+				Status:  status.Waiting,
+				Message: "operator",
+			},
+			appStatus: status.StatusInfo{
+				Status:  status.Active,
+				Message: "unit",
+			},
 			expectWorkload: false,
 			messageCheck:   "installing agent",
 		},