Add development CLI to docs

.docs/content/4.extra-topics/0.development.md

@@ -10,5 +10,63 @@ TODO
 - How to make new sources/embeds (link to the page)
 - How to use the fetchers, when to use proxiedFetcher
 - How to use the context
-- Testing of contributions
 -->
+
+## Testing using the CLI
+
+Testing can be quite difficult for this library, unit tests can't really be made because of the unreliable nature of scrapers.
+But manually testing by writing an entrypoint is also really annoying.
+
+Our solution is to make a CLI that you can use to run the scrapers, for everything else there are unit tests.
+
+### Setup
+Make a `.env` file in the root of the repository and add a TMDB api key: `MOVIE_WEB_TMDB_API_KEY=KEY_HERE`.
+Then make sure you've ran `npm i` to get all the dependencies.
+
+### Mode 1 - interactive
+
+To run the CLI without needing to learn all the arguments, simply run the following command and go with the flow.
+
+```sh
+npm run cli
+```
+
+### Mode 2 - arguments
+
+For repeatability, it can be useful to specify the arguments one by one.
+To see all the arguments, you can run the help command:
+```sh
+npm run cli -- -h
+```
+
+Then just run it with your arguments, for example:
+```sh
+npm run cli -- -sid showbox -tid 556574
+```
+
+### Examples
+
+```sh
+# Spirited away - showbox
+npm run cli -- -sid showbox -tid 129
+
+# Hamilton - flixhq
+npm run cli -- -sid flixhq -tid 556574
+
+# Arcane S1E1 - showbox
+npm run cli -- -sid zoechip -tid 94605 -s 1 -e 1
+
+# febbox mp4 - 
+npm run cli -- -sid febbox-mp4 -u URL_HERE
+```
+
+### Fetcher options
+
+The CLI comes with a few built-in fetchers:
+ - `node-fetch`: Fetch using the "node-fetch" library.
+ - `native`: Use the new fetch built into nodejs (undici).
+ - `browser`: Start up headless chrome, and run the library in that context using a proxied fetcher.
+
+::alert{type="warning"}
+The browser fetcher will require you to run `npm run build` before running the CLI. Otherwise you will get outdated results.
+::