feat: introduce dioc into hoppscotch-common

packages/dioc/test/container.spec.ts

@@ -0,0 +1,262 @@
+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 ?"
+      )
+    })
+  })
+})