feat: introduce dioc into hoppscotch-common

packages/dioc/.gitignore

@@ -0,0 +1,24 @@
+# Logs
+logs
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+lerna-debug.log*
+
+node_modules
+dist
+dist-ssr
+*.local
+
+# Editor directories and files
+.vscode/*
+!.vscode/extensions.json
+.idea
+.DS_Store
+*.suo
+*.ntvs*
+*.njsproj
+*.sln
+*.sw?

packages/dioc/README.md

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+# dioc
+
+A small and lightweight dependency injection / inversion of control system.
+
+### About
+
+`dioc` is a really simple **DI/IOC** system where you write services (which are singletons per container) that can depend on each other and emit events that can be listened upon.
+
+### Demo
+
+```ts
+import { Service, Container } from "dioc"
+
+// Here is a simple service, which you can define by extending the Service class
+// and providing an ID static field (of type string)
+export class PersistenceService extends Service {
+  // This should be unique for each container
+  public static ID = "PERSISTENCE_SERVICE"
+
+  public read(key: string): string | undefined {
+    // ...
+  }
+
+  public write(key: string, value: string) {
+    // ...
+  }
+}
+
+type TodoServiceEvent =
+  | { type: "TODO_CREATED"; index: number }
+  | { type: "TODO_DELETED"; index: number }
+
+// Services have a built in event system
+// Define the generic argument to say what are the possible emitted values
+export class TodoService extends Service<TodoServiceEvent> {
+  public static ID = "TODO_SERVICE"
+
+  // Inject persistence service into this service
+  private readonly persistence = this.bind(PersistenceService)
+
+  public todos = []
+
+  // Service constructors cannot have arguments
+  constructor() {
+    super()
+
+    this.todos = JSON.parse(this.persistence.read("todos") ?? "[]")
+  }
+
+  public addTodo(text: string) {
+    // ...
+
+    // You can access services via the bound fields
+    this.persistence.write("todos", JSON.stringify(this.todos))
+
+    // This is how you emit an event
+    this.emit({
+      type: "TODO_CREATED",
+      index,
+    })
+  }
+
+  public removeTodo(index: number) {
+    // ...
+
+    this.emit({
+      type: "TODO_DELETED",
+      index,
+    })
+  }
+}
+
+// Services need a container to run in
+const container = new Container()
+
+// You can initialize and get services using Container#bind
+// It will automatically initialize the service (and its dependencies)
+const todoService = container.bind(TodoService) // Returns an instance of TodoService
+```
+
+### Demo (Unit Test)
+
+`dioc/testing` contains `TestContainer` which lets you bind mocked services to the container.
+
+```ts
+import { TestContainer } from "dioc/testing"
+import { TodoService, PersistenceService } from "./demo.ts" // The above demo code snippet
+import { describe, it, expect, vi } from "vitest"
+
+describe("TodoService", () => {
+  it("addTodo writes to persistence", () => {
+    const container = new TestContainer()
+
+    const writeFn = vi.fn()
+
+    // The first parameter is the service to mock and the second parameter
+    // is the mocked service fields and functions
+    container.bindMock(PersistenceService, {
+      read: () => undefined, // Not really important for this test
+      write: writeFn,
+    })
+
+    // the peristence service bind in TodoService will now use the
+    // above defined mocked implementation
+    const todoService = container.bind(TodoService)
+
+    todoService.addTodo("sup")
+
+    expect(writeFn).toHaveBeenCalledOnce()
+    expect(writeFn).toHaveBeenCalledWith("todos", JSON.stringify(["sup"]))
+  })
+})
+```
+
+### Demo (Vue)
+
+`dioc/vue` contains a Vue Plugin and a `useService` composable that allows Vue components to use the defined services.
+
+In the app entry point:
+
+```ts
+import { createApp } from "vue"
+import { diocPlugin } from "dioc/vue"
+
+const app = createApp()
+
+app.use(diocPlugin, {
+  container: new Container(), // You can pass in the container you want to provide to the components here
+})
+```
+
+In your Vue components:
+
+```vue
+<script setup>
+import { TodoService } from "./demo.ts" // The above demo
+import { useService } from "dioc/vue"
+
+const todoService = useService(TodoService) // Returns an instance of the TodoService class
+</script>
+```

packages/dioc/index.d.ts

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+export { default } from "./dist/main.d.ts"
+export * from "./dist/main.d.ts"

packages/dioc/lib/container.ts

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+import { Service } from "./service"
+import { Observable, Subject } from 'rxjs'
+
+/**
+ * Stores the current container instance in the current operating context.
+ *
+ * NOTE: This should not be used outside of dioc library code
+ */
+export let currentContainer: Container | null = null
+
+/**
+ * The events emitted by the container
+ *
+ * `SERVICE_BIND` - emitted when a service is bound to the container directly or as a dependency to another service
+ * `SERVICE_INIT` - emitted when a service is initialized
+ */
+export type ContainerEvent =
+  | {
+    type: 'SERVICE_BIND';
+
+    /** The Service ID of the service being bounded (the dependency) */
+    boundeeID: string;
+
+    /**
+     * The Service ID of the bounder that is binding the boundee (the dependent)
+     *
+     * NOTE: This will be undefined if the service is bound directly to the container
+     */
+    bounderID: string | undefined
+  }
+  | {
+    type: 'SERVICE_INIT';
+
+    /** The Service ID of the service being initialized */
+    serviceID: string
+  }
+
+/**
+ * The dependency injection container, allows for services to be initialized and maintains the dependency trees.
+ */
+export class Container {
+  /** Used during the `bind` operation to detect circular dependencies */
+  private bindStack: string[] = []
+
+  /** The map of bound services to their IDs */
+  protected boundMap = new Map<string, Service<unknown>>()
+
+  /** The RxJS observable representing the event stream */
+  protected event$ = new Subject<ContainerEvent>()
+
+  /**
+   * Returns whether a container has the given service bound
+   * @param service The service to check for
+   */
+  public hasBound<
+    T extends typeof Service<any> & { ID: string }
+  >(service: T): boolean {
+    return this.boundMap.has(service.ID)
+  }
+
+  /**
+   * Returns the service bound to the container with the given ID or if not found, undefined.
+   *
+   * NOTE: This is an advanced method and should not be used as much as possible.
+   *
+   * @param serviceID The ID of the service to get
+   */
+  public getBoundServiceWithID(serviceID: string): Service<unknown> | undefined {
+    return this.boundMap.get(serviceID)
+  }
+
+  /**
+   * Binds a service to the container. This is equivalent to marking a service as a dependency.
+   * @param service The class reference of a service to bind
+   * @param bounder The class reference of the service that is binding the service (if bound directly to the container, this should be undefined)
+   */
+  public bind<T extends typeof Service<any> & { ID: string }>(
+    service: T,
+    bounder: ((typeof Service<T>) & { ID: string }) | undefined = undefined
+  ): InstanceType<T> {
+    // We need to store the current container in a variable so that we can restore it after the bind operation
+    const oldCurrentContainer = currentContainer;
+    currentContainer = this;
+
+    // If the service is already bound, return the existing instance
+    if (this.hasBound(service)) {
+      this.event$.next({
+        type: 'SERVICE_BIND',
+        boundeeID: service.ID,
+        bounderID: bounder?.ID // Return the bounder ID if it is defined, else assume its the container
+      })
+
+      return this.boundMap.get(service.ID) as InstanceType<T> // Casted as InstanceType<T> because service IDs and types are expected to match
+    }
+
+    // Detect circular dependency and throw error
+    if (this.bindStack.findIndex((serviceID) => serviceID === service.ID) !== -1) {
+      const circularServices = `${this.bindStack.join(' -> ')} -> ${service.ID}`
+
+      throw new Error(`Circular dependency detected.\nChain: ${circularServices}`)
+    }
+
+    // Push the service ID onto the bind stack to detect circular dependencies
+    this.bindStack.push(service.ID)
+
+    // Initialize the service and emit events
+
+    // NOTE: We need to cast the service to any as TypeScript thinks that the service is abstract
+    const instance: Service<any> = new (service as any)()
+
+    this.boundMap.set(service.ID, instance)
+
+    this.bindStack.pop()
+
+    this.event$.next({
+      type: 'SERVICE_INIT',
+      serviceID: service.ID,
+    })
+
+    this.event$.next({
+      type: 'SERVICE_BIND',
+      boundeeID: service.ID,
+      bounderID: bounder?.ID
+    })
+
+
+    // Restore the current container
+    currentContainer = oldCurrentContainer;
+
+    // We expect the return type to match the service definition
+    return instance as InstanceType<T>
+  }
+
+  /**
+   * Returns an iterator of the currently bound service IDs and their instances
+   */
+  public getBoundServices(): IterableIterator<[string, Service<any>]> {
+    return this.boundMap.entries()
+  }
+
+  /**
+   * Returns the public container event stream
+   */
+  public getEventStream(): Observable<ContainerEvent> {
+    return this.event$.asObservable()
+  }
+}

packages/dioc/lib/main.ts

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+export * from "./container"
+export * from "./service"

packages/dioc/lib/service.ts

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+import { Observable, Subject } from 'rxjs'
+import { Container, currentContainer } from './container'
+
+/**
+ * A Dioc service that can bound to a container and can bind dependency services.
+ *
+ * NOTE: Services cannot have a constructor that takes arguments.
+ *
+ * @template EventDef The type of events that can be emitted by the service. These will be accessible by event streams
+ */
+export abstract class Service<EventDef = {}> {
+
+  /**
+   * The internal event stream of the service
+   */
+  private event$ = new Subject<EventDef>()
+
+  /** The container the service is bound to */
+  #container: Container
+
+  constructor() {
+    if (!currentContainer) {
+      throw new Error(
+        `Tried to initialize service with no container (ID: ${ (this.constructor as any).ID })`
+      )
+    }
+
+    this.#container = currentContainer
+  }
+
+  /**
+   * Binds a dependency service into this service.
+   * @param service The class reference of the service to bind
+   */
+  protected bind<T extends typeof Service<any> & { ID: string }>(service: T): InstanceType<T> {
+    if (!currentContainer) {
+      throw new Error('No currentContainer defined.')
+    }
+
+    return currentContainer.bind(service, this.constructor as typeof Service<any> & { ID: string })
+  }
+
+  /**
+   * Returns the container the service is bound to
+   */
+  protected getContainer(): Container {
+    return this.#container
+  }
+
+  /**
+   * Emits an event on the service's event stream
+   * @param event The event to emit
+   */
+  protected emit(event: EventDef) {
+    this.event$.next(event)
+  }
+
+  /**
+   * Returns the event stream of the service
+   */
+  public getEventStream(): Observable<EventDef> {
+
+    return this.event$.asObservable()
+  }
+}

packages/dioc/lib/testing.ts

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+import { Container, Service } from "./main";
+
+/**
+ * A container that can be used for writing tests, contains additional methods
+ * for binding suitable for writing tests. (see `bindMock`).
+ */
+export class TestContainer extends Container {
+
+  /**
+   * Binds a mock service to the container.
+   *
+   * @param service
+   * @param mock
+   */
+  public bindMock<
+    T extends typeof Service<any> & { ID: string },
+    U extends Partial<InstanceType<T>>
+  >(service: T, mock: U): U {
+    if (this.boundMap.has(service.ID)) {
+      throw new Error(`Service '${service.ID}' already bound to container. Did you already call bindMock on this ?`)
+    }
+
+    this.boundMap.set(service.ID, mock as any)
+
+    this.event$.next({
+      type: "SERVICE_BIND",
+      boundeeID: service.ID,
+      bounderID: undefined,
+    })
+
+    return mock
+  }
+}

packages/dioc/lib/vue.ts

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+import { Plugin, inject } from "vue"
+import { Container } from "./container"
+import { Service } from "./service"
+
+const VUE_CONTAINER_KEY = Symbol()
+
+// TODO: Some Vue version issue with plugin generics is breaking type checking
+/**
+ * The Vue Dioc Plugin, this allows the composables to work and access the container
+ *
+ * NOTE: Make sure you add `vue` as dependency to be able to use this plugin (duh)
+ */
+export const diocPlugin: Plugin = {
+  install(app, { container }) {
+    app.provide(VUE_CONTAINER_KEY, container)
+  }
+}
+
+/**
+ * A composable that binds a service to a Vue Component
+ *
+ * @param service The class reference of the service to bind
+ */
+export function useService<
+  T extends typeof Service<any> & { ID: string }
+>(service: T): InstanceType<T> {
+  const container = inject(VUE_CONTAINER_KEY) as Container | undefined | null
+
+  if (!container) {
+    throw new Error("Container not found, did you forget to install the dioc plugin?")
+  }
+
+  return container.bind(service)
+}

packages/dioc/package.json

@@ -0,0 +1,54 @@
+{
+  "name": "dioc",
+  "private": true,
+  "version": "0.1.0",
+  "type": "module",
+  "files": [
+    "dist",
+    "index.d.ts"
+  ],
+  "main": "./dist/counter.umd.cjs",
+  "module": "./dist/counter.js",
+  "types": "./index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./dist/main.d.ts",
+      "require": "./dist/index.cjs",
+      "import": "./dist/index.js"
+    },
+    "./vue": {
+      "types": "./dist/vue.d.ts",
+      "require": "./dist/vue.cjs",
+      "import": "./dist/vue.js"
+    },
+    "./testing": {
+      "types": "./dist/testing.d.ts",
+      "require": "./dist/testing.cjs",
+      "import": "./dist/testing.js"
+    }
+  },
+  "scripts": {
+    "dev": "vite",
+    "build": "vite build && tsc --emitDeclarationOnly",
+    "prepare": "pnpm run build",
+    "test": "vitest run",
+    "do-test": "pnpm run test",
+    "test:watch": "vitest"
+  },
+  "devDependencies": {
+    "typescript": "^4.9.4",
+    "vite": "^4.0.4",
+    "vitest": "^0.29.3"
+  },
+  "dependencies": {
+    "rxjs": "^7.8.1"
+  },
+  "peerDependencies": {
+    "vue": "^3.2.25"
+  },
+  "peerDependenciesMeta": {
+    "vue": {
+      "optional": true
+    }
+  }
+}

packages/dioc/test/container.spec.ts

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+import { it, expect, describe, vi } from "vitest"
+import { Service } from "../lib/service"
+import { Container, currentContainer, ContainerEvent } from "../lib/container"
+
+class TestServiceA extends Service {
+  public static ID = "TestServiceA"
+}
+
+class TestServiceB extends Service {
+  public static ID = "TestServiceB"
+
+  // Marked public to allow for testing
+  public readonly serviceA = this.bind(TestServiceA)
+}
+
+describe("Container", () => {
+  describe("getBoundServiceWithID", () => {
+    it("returns the service instance if it is bound to the container", () => {
+      const container = new Container()
+
+      const service = container.bind(TestServiceA)
+
+      expect(container.getBoundServiceWithID(TestServiceA.ID)).toBe(service)
+    })
+
+    it("returns undefined if the service is not bound to the container", () => {
+      const container = new Container()
+
+      expect(container.getBoundServiceWithID(TestServiceA.ID)).toBeUndefined()
+    })
+  })
+
+  describe("bind", () => {
+    it("correctly binds the service to it", () => {
+      const container = new Container()
+
+      const service = container.bind(TestServiceA)
+
+      // @ts-expect-error getContainer is defined as a protected property, but we are leveraging it here to check
+      expect(service.getContainer()).toBe(container)
+    })
+
+    it("after bind, the current container is set back to its previous value", () => {
+      const originalValue = currentContainer
+
+      const container = new Container()
+      container.bind(TestServiceA)
+
+      expect(currentContainer).toBe(originalValue)
+    })
+
+    it("dependent services are registered in the same container", () => {
+      const container = new Container()
+
+      const serviceB = container.bind(TestServiceB)
+
+      // @ts-expect-error getContainer is defined as a protected property, but we are leveraging it here to check
+      expect(serviceB.serviceA.getContainer()).toBe(container)
+    })
+
+    it("binding an already initialized service returns the initialized instance (services are singletons)", () => {
+      const container = new Container()
+
+      const serviceA = container.bind(TestServiceA)
+      const serviceA2 = container.bind(TestServiceA)
+
+      expect(serviceA).toBe(serviceA2)
+    })
+
+    it("binding a service which is a dependency of another service returns the same instance created from the dependency resolution (services are singletons)", () => {
+      const container = new Container()
+
+      const serviceB = container.bind(TestServiceB)
+      const serviceA = container.bind(TestServiceA)
+
+      expect(serviceB.serviceA).toBe(serviceA)
+    })
+
+    it("binding an initialized service as a dependency returns the same instance", () => {
+      const container = new Container()
+
+      const serviceA = container.bind(TestServiceA)
+      const serviceB = container.bind(TestServiceB)
+
+      expect(serviceB.serviceA).toBe(serviceA)
+    })
+
+    it("container emits an init event when an uninitialized service is initialized via bind and event only called once", () => {
+      const container = new Container()
+
+      const serviceFunc = vi.fn<
+        [ContainerEvent & { type: "SERVICE_INIT" }],
+        void
+      >()
+
+      container.getEventStream().subscribe((ev) => {
+        if (ev.type === "SERVICE_INIT") {
+          serviceFunc(ev)
+        }
+      })
+
+      const instance = container.bind(TestServiceA)
+
+      expect(serviceFunc).toHaveBeenCalledOnce()
+      expect(serviceFunc).toHaveBeenCalledWith(<ContainerEvent>{
+        type: "SERVICE_INIT",
+        serviceID: TestServiceA.ID,
+      })
+    })
+
+    it("the bind event emitted has an undefined bounderID when the service is bound directly to the container", () => {
+      const container = new Container()
+
+      const serviceFunc = vi.fn<
+        [ContainerEvent & { type: "SERVICE_BIND" }],
+        void
+      >()
+
+      container.getEventStream().subscribe((ev) => {
+        if (ev.type === "SERVICE_BIND") {
+          serviceFunc(ev)
+        }
+      })
+
+      container.bind(TestServiceA)
+
+      expect(serviceFunc).toHaveBeenCalledOnce()
+      expect(serviceFunc).toHaveBeenCalledWith(<ContainerEvent>{
+        type: "SERVICE_BIND",
+        boundeeID: TestServiceA.ID,
+        bounderID: undefined,
+      })
+    })
+
+    it("the bind event emitted has the correct bounderID when the service is bound to another service", () => {
+      const container = new Container()
+
+      const serviceFunc = vi.fn<
+        [ContainerEvent & { type: "SERVICE_BIND" }],
+        void
+      >()
+
+      container.getEventStream().subscribe((ev) => {
+        // We only care about the bind event of TestServiceA
+        if (ev.type === "SERVICE_BIND" && ev.boundeeID === TestServiceA.ID) {
+          serviceFunc(ev)
+        }
+      })
+
+      container.bind(TestServiceB)
+
+      expect(serviceFunc).toHaveBeenCalledOnce()
+      expect(serviceFunc).toHaveBeenCalledWith(<ContainerEvent>{
+        type: "SERVICE_BIND",
+        boundeeID: TestServiceA.ID,
+        bounderID: TestServiceB.ID,
+      })
+    })
+  })
+
+  describe("hasBound", () => {
+    it("returns true if the given service is bound to the container", () => {
+      const container = new Container()
+
+      container.bind(TestServiceA)
+
+      expect(container.hasBound(TestServiceA)).toEqual(true)
+    })
+
+    it("returns false if the given service is not bound to the container", () => {
+      const container = new Container()
+
+      expect(container.hasBound(TestServiceA)).toEqual(false)
+    })
+
+    it("returns true when the service is bound because it is a dependency of another service", () => {
+      const container = new Container()
+
+      container.bind(TestServiceB)
+
+      expect(container.hasBound(TestServiceA)).toEqual(true)
+    })
+  })
+
+  describe("getEventStream", () => {
+    it("returns an observable which emits events correctly when services are initialized", () => {
+      const container = new Container()
+
+      const serviceFunc = vi.fn<
+        [ContainerEvent & { type: "SERVICE_INIT" }],
+        void
+      >()
+
+      container.getEventStream().subscribe((ev) => {
+        if (ev.type === "SERVICE_INIT") {
+          serviceFunc(ev)
+        }
+      })
+
+      container.bind(TestServiceB)
+
+      expect(serviceFunc).toHaveBeenCalledTimes(2)
+      expect(serviceFunc).toHaveBeenNthCalledWith(1, <ContainerEvent>{
+        type: "SERVICE_INIT",
+        serviceID: TestServiceA.ID,
+      })
+      expect(serviceFunc).toHaveBeenNthCalledWith(2, <ContainerEvent>{
+        type: "SERVICE_INIT",
+        serviceID: TestServiceB.ID,
+      })
+    })
+
+    it("returns an observable which emits events correctly when services are bound", () => {
+      const container = new Container()
+
+      const serviceFunc = vi.fn<
+        [ContainerEvent & { type: "SERVICE_BIND" }],
+        void
+      >()
+
+      container.getEventStream().subscribe((ev) => {
+        if (ev.type === "SERVICE_BIND") {
+          serviceFunc(ev)
+        }
+      })
+
+      container.bind(TestServiceB)
+
+      expect(serviceFunc).toHaveBeenCalledTimes(2)
+      expect(serviceFunc).toHaveBeenNthCalledWith(1, <ContainerEvent>{
+        type: "SERVICE_BIND",
+        boundeeID: TestServiceA.ID,
+        bounderID: TestServiceB.ID,
+      })
+      expect(serviceFunc).toHaveBeenNthCalledWith(2, <ContainerEvent>{
+        type: "SERVICE_BIND",
+        boundeeID: TestServiceB.ID,
+        bounderID: undefined,
+      })
+    })
+  })
+
+  describe("getBoundServices", () => {
+    it("returns an iterator over all services bound to the container in the format [service id, service instance]", () => {
+      const container = new Container()
+
+      const instanceB = container.bind(TestServiceB)
+      const instanceA = instanceB.serviceA
+
+      expect(Array.from(container.getBoundServices())).toEqual([
+        [TestServiceA.ID, instanceA],
+        [TestServiceB.ID, instanceB],
+      ])
+    })
+
+    it("returns an empty iterator if no services are bound", () => {
+      const container = new Container()
+
+      expect(Array.from(container.getBoundServices())).toEqual([])
+    })
+  })
+})

packages/dioc/test/service.spec.ts

@@ -0,0 +1,66 @@
+import { describe, expect, it, vi } from "vitest"
+import { Service, Container } from "../lib/main"
+
+class TestServiceA extends Service {
+  public static ID = "TestServiceA"
+}
+
+class TestServiceB extends Service<"test"> {
+  public static ID = "TestServiceB"
+
+  // Marked public to allow for testing
+  public readonly serviceA = this.bind(TestServiceA)
+
+  public emitTestEvent() {
+    this.emit("test")
+  }
+}
+
+describe("Service", () => {
+  describe("constructor", () => {
+    it("throws an error if the service is initialized without a container", () => {
+      expect(() => new TestServiceA()).toThrowError(
+        "Tried to initialize service with no container (ID: TestServiceA)"
+      )
+    })
+  })
+
+  describe("bind", () => {
+    it("correctly binds the dependency service using the container", () => {
+      const container = new Container()
+
+      const serviceA = container.bind(TestServiceA)
+
+      const serviceB = container.bind(TestServiceB)
+      expect(serviceB.serviceA).toBe(serviceA)
+    })
+  })
+
+  describe("getContainer", () => {
+    it("returns the container the service is bound to", () => {
+      const container = new Container()
+
+      const serviceA = container.bind(TestServiceA)
+
+      // @ts-expect-error getContainer is a protected member, we are just using it to help with testing
+      expect(serviceA.getContainer()).toBe(container)
+    })
+  })
+
+  describe("getEventStream", () => {
+    it("returns the valid event stream of the service", () => {
+      const container = new Container()
+
+      const serviceB = container.bind(TestServiceB)
+
+      const serviceFunc = vi.fn()
+
+      serviceB.getEventStream().subscribe(serviceFunc)
+
+      serviceB.emitTestEvent()
+
+      expect(serviceFunc).toHaveBeenCalledOnce()
+      expect(serviceFunc).toHaveBeenCalledWith("test")
+    })
+  })
+})

packages/dioc/test/test-container.spec.ts

@@ -0,0 +1,92 @@
+import { describe, expect, it, vi } from "vitest"
+import { TestContainer } from "../lib/testing"
+import { Service } from "../lib/service"
+import { ContainerEvent } from "../lib/container"
+
+class TestServiceA extends Service {
+  public static ID = "TestServiceA"
+
+  public test() {
+    return "real"
+  }
+}
+
+class TestServiceB extends Service {
+  public static ID = "TestServiceB"
+
+  // declared public to help with testing
+  public readonly serviceA = this.bind(TestServiceA)
+
+  public test() {
+    return this.serviceA.test()
+  }
+}
+
+describe("TestContainer", () => {
+  describe("bindMock", () => {
+    it("returns the fake service defined", () => {
+      const container = new TestContainer()
+
+      const fakeService = {
+        test: () => "fake",
+      }
+
+      const result = container.bindMock(TestServiceA, fakeService)
+
+      expect(result).toBe(fakeService)
+    })
+
+    it("new services bound to the container get the mock service", () => {
+      const container = new TestContainer()
+
+      const fakeServiceA = {
+        test: () => "fake",
+      }
+
+      container.bindMock(TestServiceA, fakeServiceA)
+
+      const serviceB = container.bind(TestServiceB)
+
+      expect(serviceB.serviceA).toBe(fakeServiceA)
+    })
+
+    it("container emits SERVICE_BIND event", () => {
+      const container = new TestContainer()
+
+      const fakeServiceA = {
+        test: () => "fake",
+      }
+
+      const serviceFunc = vi.fn<[ContainerEvent, void]>()
+
+      container.getEventStream().subscribe((ev) => {
+        serviceFunc(ev)
+      })
+
+      container.bindMock(TestServiceA, fakeServiceA)
+
+      expect(serviceFunc).toHaveBeenCalledOnce()
+      expect(serviceFunc).toHaveBeenCalledWith(<ContainerEvent>{
+        type: "SERVICE_BIND",
+        boundeeID: TestServiceA.ID,
+        bounderID: undefined,
+      })
+    })
+
+    it("throws if service already bound", () => {
+      const container = new TestContainer()
+
+      const fakeServiceA = {
+        test: () => "fake",
+      }
+
+      container.bindMock(TestServiceA, fakeServiceA)
+
+      expect(() => {
+        container.bindMock(TestServiceA, fakeServiceA)
+      }).toThrowError(
+        "Service 'TestServiceA' already bound to container. Did you already call bindMock on this ?"
+      )
+    })
+  })
+})

packages/dioc/testing.d.ts

@@ -0,0 +1,2 @@
+export { default } from "./dist/testing.d.ts"
+export * from "./dist/testing.d.ts"

packages/dioc/tsconfig.json

@@ -0,0 +1,21 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "useDefineForClassFields": true,
+    "module": "ESNext",
+    "lib": ["ESNext", "DOM"],
+    "moduleResolution": "Node",
+    "strict": true,
+    "declaration": true,
+    "sourceMap": true,
+    "outDir": "dist",
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "esModuleInterop": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noImplicitReturns": true,
+    "skipLibCheck": true
+  },
+  "include": ["lib"]
+}

packages/dioc/vite.config.ts

@@ -0,0 +1,16 @@
+import { defineConfig } from 'vite'
+
+export default defineConfig({
+  build: {
+    lib: {
+      entry: {
+        index: './lib/main.ts',
+        vue: './lib/vue.ts',
+        testing: './lib/testing.ts',
+      },
+    },
+    rollupOptions: {
+      external: ['vue'],
+    }
+  },
+})

packages/dioc/vitest.config.ts

@@ -0,0 +1,7 @@
+import { defineConfig } from "vitest/config"
+
+export default defineConfig({
+  test: {
+
+  }
+})

packages/dioc/vue.d.ts

@@ -0,0 +1,2 @@
+export { default } from "./dist/vue.d.ts"
+export * from "./dist/vue.d.ts"

packages/hoppscotch-common/package.json

@@ -18,6 +18,7 @@
     "do-lintfix": "pnpm run lintfix"
   },
   "dependencies": {
+    "dioc": "workspace:^",
     "@apidevtools/swagger-parser": "^10.1.0",
     "@codemirror/autocomplete": "^6.0.3",
     "@codemirror/commands": "^6.0.1",

packages/hoppscotch-common/src/modules/dioc.ts

@@ -0,0 +1,13 @@
+import { HoppModule } from "."
+import { Container } from "dioc"
+import { diocPlugin } from "dioc/vue"
+
+export default <HoppModule>{
+  onVueAppInit(app) {
+    // TODO: look into this
+    // @ts-expect-error Something weird with Vue versions
+    app.use(diocPlugin, {
+      container: new Container(),
+    })
+  },
+}