statusoptional: Embed nil check in checkStatusStruct

Return early from the method when statusType is nil, as we can't
reliably expect all callers to check for passed arguments before calling
the function.

Hopefully fixes #90

Author: mandre

pkg/analysis/statusoptional/analyzer.go

@@ -85,18 +85,14 @@ func (a *analyzer) run(pass *analysis.Pass) (any, error) {
 		}
 
 		statusStructType := getStructFromField(pass, field)
-		if statusStructType == nil {
-			return
-		}
-
 		a.checkStatusStruct(pass, statusStructType, markersAccess, jsonTags)
 	})
 
 	return nil, nil //nolint:nilnil
 }
 
 func (a *analyzer) checkStatusStruct(pass *analysis.Pass, statusType *ast.StructType, markersAccess markershelper.Markers, jsonTags extractjsontags.StructFieldTags) {
-	if statusType.Fields == nil || statusType.Fields.List == nil {
+	if statusType == nil || statusType.Fields == nil || statusType.Fields.List == nil {
 		return
 	}