The purpose of this document is to explain how Void's codebase works. If you want build instructions instead, see [Contributing](https://github.com/voideditor/void/blob/main/HOW_TO_CONTRIBUTE.md).
Here's a VSCode rundown if you're just getting started with Void. You can also see Microsoft's [wiki](https://github.com/microsoft/vscode/wiki/Source-Code-Organization) for some pictures. VSCode is an Electron app. Electron runs two processes: a **main** process (for internals) and a **browser** process (browser means HTML in general, not just "web browser").
- An **Editor** is the thing that you type your code in. If you have 10 tabs open, that's just one editor! Editors contain tabs (or "models").
- A **Model** is an internal representation of a file's contents. It's shared between editors (for example, if you press `Cmd+\` to make a new editor, then the model of a file like `A.ts` is shared between them. Two editors, one model. That's how changes sync.).
- Each model has a **URI** it represents, like `/Users/.../my_file.txt`. (A URI or "resource" is generally just a path).
- The **Workbench** is the wrapper that contains all the editors, the terminal, the file system tree, etc.
- Usually you use the `ITextModel` type for models and the `ICodeEditor` type for editors. There aren't that many other types.
- VSCode is organized into "**Services**". A service is just a class that mounts a single time (in computer science theory this is called a "singleton"). You can register services with `registerSingleton` so that you can easily use them in any constructor with `@<Service>`. See _dummyContrib for an example we put together on how to register them. The registration is the same every time.
- You can run actions as a user by pressing Cmd+Shift+P (opens the command pallete), or you can run them internally by using the commandService to call them by ID. We use actions to register keybinding listeners like Cmd+L, Cmd+K, etc. The nice thing about actions is the user can change the keybindings.
Here's a picture of all the dependencies that are relevent between the time you first send a message through Void's sidebar, and the time a request is sent to your provider.
Sending LLM messages from the main process avoids CSP issues with local providers and lets us use node_modules more easily.
This is what allows Void to quickly apply code even on 1000-line files. It's the same as asking the LLM to press Ctrl+F and enter in a search/replace query.
The `editCodeService` file runs Apply. The same exact code is also used when the LLM calls the Edit tool, and when you submit Cmd+K. Just different versions of Fast/Slow Apply mode.
- A **DiffZone** is a {startLine, endLine} region of text where we compute and show red/green areas, or **Diffs**. When any changes are made to a file, we loop through all the DiffAreas on that file and refresh its Diffs.
- A **DiffArea** is a generalization that just tracks line numbers like a DiffZone.
- When you click Apply, we create a **DiffZone** over that the full file so that any changes that the LLM makes will show up in red/green. We then stream the change.
- When an LLM calls Edit, it's really calling Apply.
- When you submit Cmd+K, it's the same as Apply except we create a smaller DiffZone (not on the whole file).
When Void wants to change your code, it just writes to a text model. This means all you need to know to write to a file is its URI - you don't have to load it, save it, etc. There are some annoying background URI/model things to think about to get this to work, but we handled them all in `voidModelService`.
We have a service `voidSettingsService` that stores all your Void settings (providers, models, global Void settings, etc). Imagine this as an implicit dependency for any of the core Void services:
`editCodeService`'s data structures contain all the information about changes that the user needs to review. However, they don't store that information in a useful format. We wrote the following service to get a more useful derived state:
- [How VSCode's sourcecode is organized](https://github.com/microsoft/vscode/wiki/Source-Code-Organization) - this explains where the entry point files are, what `browser/` and `common/` mean, etc. This is the most important read on this whole list! We recommend reading the whole thing.
- [Built-in VSCode styles](https://code.visualstudio.com/api/references/theme-color) - CSS variables that are built into VSCode. Use `var(--vscode-{theme but replacing . with -})`. You can also see their [Webview theming guide](https://code.visualstudio.com/api/extension-guides/webview#theming-webview-content).
- ["Contributes" Guide](https://code.visualstudio.com/api/references/contribution-points) - the `"contributes"` part of `package.json` is how an extension mounts.
- [The Full VSCode Extension API](https://code.visualstudio.com/api/references/vscode-api) - look on the right side for organization. The [bottom](https://code.visualstudio.com/api/references/vscode-api#api-patterns) of the page is easy to miss but is useful - cancellation tokens, events, disposables.
- [Activation events](https://code.visualstudio.com/api/references/activation-events) you can define in `package.json` (not the most useful).
