From 389eec39653abeeac6b596fbf508378a9bc34f65 Mon Sep 17 00:00:00 2001
From: Koen Bekkenutte <2912652+kbekkenutte@users.noreply.github.com>
Date: Mon, 14 Jun 2021 22:27:25 +0800
Subject: [PATCH] Perf tweak

---
 src/ScenarioTests.Generator/ScenarioTestGenerator.cs | 2 +-
 src/ScenarioTests.Generator/SyntaxReceiver.cs        | 7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/ScenarioTests.Generator/ScenarioTestGenerator.cs b/src/ScenarioTests.Generator/ScenarioTestGenerator.cs
index 1fe9a30..a5126d3 100644
--- a/src/ScenarioTests.Generator/ScenarioTestGenerator.cs
+++ b/src/ScenarioTests.Generator/ScenarioTestGenerator.cs
@@ -24,7 +24,7 @@ public void Initialize(GeneratorInitializationContext context) =>
         public void Execute(GeneratorExecutionContext context)
         {
             // retrieve the populated receiver 
-            if (context.SyntaxReceiver is not SyntaxReceiver receiver)
+            if (context.SyntaxReceiver is not SyntaxReceiver receiver || receiver.ScenarioCandidates is null)
             {
                 return;
             }
diff --git a/src/ScenarioTests.Generator/SyntaxReceiver.cs b/src/ScenarioTests.Generator/SyntaxReceiver.cs
index 5c24401..4614488 100644
--- a/src/ScenarioTests.Generator/SyntaxReceiver.cs
+++ b/src/ScenarioTests.Generator/SyntaxReceiver.cs
@@ -7,7 +7,7 @@ namespace ScenarioTests.Generator
 {
     public class SyntaxReceiver : ISyntaxReceiver
     {
-        public List<MethodDeclarationSyntax> ScenarioCandidates { get; } = new List<MethodDeclarationSyntax>();
+        public List<MethodDeclarationSyntax> ScenarioCandidates { get; private set; }
 
         public void OnVisitSyntaxNode(SyntaxNode syntaxNode)
         {
@@ -20,6 +20,11 @@ public void OnVisitSyntaxNode(SyntaxNode syntaxNode)
 
                 if (hasScenarioAttribute)
                 {
+                    if (ScenarioCandidates is null)
+                    {
+                        ScenarioCandidates = new();
+                    }
+
                     ScenarioCandidates.Add(methodDeclarationSyntax);
                 }
             }