# React Inversion Of Control with Unit Tests using Jest and Enzyme ## Summary This web part is provided as an example of implementing an IoC (Inversion of Control) pattern, primarily to enable unit testing, in the context of a SharePoint Framework web part. Following this pattern greatly improves the modularity, maintainability, and testability of the code. The example includes 100% test coverage, using Jest and Enzyme, of .ts and .tsx files, excluding *WebPart.ts files. A dependency resolver class specific to a web part class is used to map web part properties to component properties and create any dependent services/providers. This pattern is implemented to separate testable logic from the untestable *WebPart.ts file and hence ensure that all relevant web part logic is tested. To this end, a Service class is paired with a ServiceExecutor class which should extract the actual service requests from other service logic ensuring that the Service class remains fully testable. *Executor classes are excluded from test coverage as they cannot be unit tested by design - as they are points integration. Included in the coverage is a cache and logger class, along with a service class that fetches data asynchronously using @pnp/sp 2.x The example also includes a pipeline definition .yaml file for Azure DevOps CI build pipeline (/pipelines/) which includes the build, running tests, and posting the test coverage results. ![Sample SPFx Web Part implementing IoC pattern](./assets/preview.jpg) ## Compatibility ![SPFx 1.10](https://img.shields.io/badge/SPFx-1.10.0-green.svg) ![Node.js v10 | v8](https://img.shields.io/badge/Node.js-v10%20%7C%20v8-green.svg) ![Compatible with SharePoint Online](https://img.shields.io/badge/SharePoint%20Online-Compatible-green.svg) ![Does not work with SharePoint 2019](https://img.shields.io/badge/SharePoint%20Server%202019-Incompatible-red.svg) ![Does not work with SharePoint 2016 (Feature Pack 2)](https://img.shields.io/badge/SharePoint%20Server%202016%20(Feature%20Pack%202)-Incompatible-red.svg "SharePoint Server 2016 Feature Pack 2 requires SPFx 1.1") ![Local Workbench Compatible](https://img.shields.io/badge/Local%20Workbench-Compatible-green.svg) ![Hosted Workbench Compatible](https://img.shields.io/badge/Hosted%20Workbench-Compatible-green.svg) ## Applies to * [SharePoint Framework](https://docs.microsoft.com/sharepoint/dev/spfx/sharepoint-framework-overview) * [Office 365 tenant](https://docs.microsoft.com/sharepoint/dev/spfx/set-up-your-development-environment) ## Solution Solution|Author(s) --------|--------- react-ioc-tests | [Paul Ryan](https://github.com/paulryan) ## Version history Version|Date|Comments -------|----|-------- 1.0|March 20, 2019|Initial release ## Minimal Path to Awesome - Clone this repository - in the command line run: - `npm install` - `npm bundle` - *`npm test`* - `gulp serve` ## Features This web part is provided as an example of implementing an IoC (Inversion of Control) pattern in the context of a SharePoint Framework web part for maximising testability. This Web Part illustrates the following concepts on top of the SharePoint Framework: - Inversion of Control pattern - Unit testing with Jest and Enzyme - Azure DevOps CI Build Pipeline yaml definition file, includes running tests and checking code coverage ## References https://github.com/pnp/sp-dev-fx-webparts/tree/main/samples/react-jest-testing https://blog.velingeorgiev.com/unit-test-your-sharepoint-framework-solution-with-jest https://www.eliostruyf.com/sharepoint-framework-unit-tests-with-jest/ https://github.com/estruyf/spfx-testing-jest ## Help We do not support samples, but we this community is always willing to help, and we want to improve these samples. We use GitHub to track issues, which makes it easy for community members to volunteer their time and help resolve issues. If you're having issues building the solution, please run [spfx doctor](https://pnp.github.io/cli-microsoft365/cmd/spfx/spfx-doctor/) from within the solution folder to diagnose incompatibility issues with your environment. You can try looking at [issues related to this sample](https://github.com/pnp/sp-dev-fx-webparts/issues?q=label%3Areact-ioc-tests) to see if anybody else is having the same issues. You can also try looking at [discussions related to this sample](https://github.com/pnp/sp-dev-fx-webparts/discussions?discussions_q=label%3Areact-ioc-tests) and see what the community is saying. If you encounter any issues while using this sample, [create a new issue](https://github.com/pnp/sp-dev-fx-webparts/issues/new?assignees=&labels=Needs%3A+Triage+%3Amag%3A%2Ctype%3Abug-suspected&template=bug-report.yml&sample=react-ioc-tests&authors=@paulryan&title=react-ioc-tests%20-%20). For questions regarding this sample, [create a new question](https://github.com/pnp/sp-dev-fx-webparts/issues/new?assignees=&labels=Needs%3A+Triage+%3Amag%3A%2Ctype%3Abug-suspected&template=question.yml&sample=react-ioc-tests&authors=@paulryan&title=react-ioc-tests%20-%20). Finally, if you have an idea for improvement, [make a suggestion](https://github.com/pnp/sp-dev-fx-webparts/issues/new?assignees=&labels=Needs%3A+Triage+%3Amag%3A%2Ctype%3Abug-suspected&template=suggestion.yml&sample=react-ioc-tests&authors=@paulryan&title=react-ioc-tests%20-%20). ## Disclaimer **THIS CODE IS PROVIDED *AS IS* WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING ANY IMPLIED WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABILITY, OR NON-INFRINGEMENT.**