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wessberg / DI

A compile-time powered Dependency-Injection container for Typescript that holds services and can produce instances of them as required.
MIT License
258 stars 6 forks source link

Changes for your consideration... #7

Open cmidgley opened 2 years ago

cmidgley commented 2 years ago

Hi - loving DI, using it daily. Great tool, with a really tiny footprint. I've been living in my own fork for a while, though I did (hand merge) your latest changes in today. I have some changes (in addition to the ones I wrote up just a bit ago on a couple of other issues here) that if they were pulled, I could remove my fork and use your repo - so wanted to see if these were interesting or not!

A great benefit of DI is how small it is, and a platform I target (along with Node) is called Moddable. It's a (nearly) fully compliant ES2021 implementation of JS for embedded microcontrollers, and it works great with DI and TypeScript. For it to link / build, it needs a file called manifest.json. Adding this file would not change anything about DI, but would enable building on Moddable.

The other change is that I added a static getter that acts as a singleton to retrieve an instance of DIContainer. With my monorepo and how I organize tests, it's really nice to be able to say DIContainer.container().get<MyType>(), and this way the container is shared across all my cross-linked projects in my monorepo (since it is a shared singleton instance of DIContainer.

One thing I do a lot of, by the way, is register in a library the various injectables (in it's index.js) so when the library is referenced, all injectables are ready and waiting. Then, in my test code (often in a different library), I commonly register the same type, but pointing to a mock or spy instance. It's great that DI handles that cleanly with overriding a previously registered type. Not sure if that was by design or intentional, but it's a wonderful capability that I wanted to mention in case future changes might disrupt that behavior!

If you are interested, I can create a new fresh branch and apply just the select needed changes with updates to the README accordingly and do a pull for your review.

Let me know your thoughts, and it's great to see you updating the code base! Thanks.

wessberg commented 2 years ago

Hi there @cmidgley.

Thanks, I'm very glad you like it and see value in the tool. I definitely want to help you out here, and I am open to adding first-hand support to Moddable.

Feel free to come up with a PR, and I'll take a look at it. Thanks again!