From 113649441eef69aa63b0c846fcbb4ec48226e830 Mon Sep 17 00:00:00 2001
From: Julian Meyer <julian.meyer@freenet.ag>
Date: Mon, 14 Apr 2025 08:12:39 +0200
Subject: [PATCH] Prevent singletons with container-scoped dependencies by
 passing singleton-information within the resolution context and checking it
 during resolution.

---
 src/dependency-container.ts | 8 ++++++++
 src/resolution-context.ts   | 1 +
 2 files changed, 9 insertions(+)

diff --git a/src/dependency-container.ts b/src/dependency-container.ts
index e829362..4d45c43 100644
--- a/src/dependency-container.ts
+++ b/src/dependency-container.ts
@@ -240,6 +240,13 @@ class InternalDependencyContainer implements DependencyContainer {
 
     this.executePreResolutionInterceptor<T>(token, "Single");
 
+    // Using a container scoped registration within a singleton is not allowed
+    if(registration && registration.options.lifecycle === Lifecycle.ContainerScoped && context.isSingleton) {
+      throw new Error(
+        `Attempted to use a container scoped registration "${token.toString()}" within a singleton`
+      );
+    }
+
     if (registration) {
       const result = this.resolveRegistration(registration, context) as T;
       this.executePostResolutionInterceptor(token, result, "Single");
@@ -313,6 +320,7 @@ class InternalDependencyContainer implements DependencyContainer {
     const isContainerScoped =
       registration.options.lifecycle === Lifecycle.ContainerScoped;
 
+    context.isSingleton = isSingleton;
     const returnInstance = isSingleton || isContainerScoped;
 
     let resolved: T;
diff --git a/src/resolution-context.ts b/src/resolution-context.ts
index 4f93da1..d69132b 100644
--- a/src/resolution-context.ts
+++ b/src/resolution-context.ts
@@ -2,4 +2,5 @@ import {Registration} from "./dependency-container";
 
 export default class ResolutionContext {
   scopedResolutions: Map<Registration, any> = new Map();
+  isSingleton: boolean = false;
 }