mirror of
https://github.com/oven-sh/bun
synced 2026-02-02 15:08:46 +00:00
## Summary
Add support for in-memory entrypoints and files in `Bun.build` via the
`files` option:
```ts
await Bun.build({
entrypoints: ["/app/index.ts"],
files: {
"/app/index.ts": `
import { greet } from "./greet.ts";
console.log(greet("World"));
`,
"/app/greet.ts": `
export function greet(name: string) {
return "Hello, " + name + "!";
}
`,
},
});
```
### Features
- **Bundle entirely from memory**: No files on disk needed
- **Override files on disk**: In-memory files take priority over disk
files
- **Mix disk and virtual files**: Real files can import virtual files
and vice versa
- **Multiple content types**: Supports `string`, `Blob`, `TypedArray`,
and `ArrayBuffer`
### Use Cases
- Code generation at build time
- Injecting build-time constants
- Testing with mock modules
- Bundling dynamically generated code
- Overriding configuration files for different environments
### Implementation Details
- Added `FileMap` struct in `JSBundler.zig` with `resolve`, `get`,
`contains`, `fromJS`, and `deinit` methods
- Uses `"memory"` namespace to avoid `pathWithPrettyInitialized`
allocation issues during linking phase
- FileMap checks added in:
- `runResolver` (entry point resolution)
- `runResolutionForParseTask` (import resolution)
- `enqueueEntryPoints` (entry point handling)
- `getCodeForParseTaskWithoutPlugins` (file content reading)
- Root directory defaults to cwd when all entrypoints are in the FileMap
- Added TypeScript types with JSDoc documentation
- Added bundler documentation with examples
## Test plan
- [x] Basic in-memory file bundling
- [x] In-memory files with absolute imports
- [x] In-memory files with relative imports (same dir, subdirs, parent
dirs)
- [x] Nested/chained imports between in-memory files
- [x] TypeScript and JSX support
- [x] Blob, Uint8Array, and ArrayBuffer content types
- [x] Re-exports and default exports
- [x] In-memory file overrides real file on disk
- [x] Real file on disk imports in-memory file via relative path
- [x] Mixed disk and memory files with complex import graphs
Run tests with: `bun bd test test/bundler/bundler_files.test.ts`
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
TypeScript types for Bun
These are the type definitions for Bun's JavaScript runtime APIs.
Installation
Install the @types/bun npm package:
# yarn/npm/pnpm work too
# @types/bun is an ordinary npm package
bun add -D @types/bun
That's it! VS Code and TypeScript automatically load @types/* packages into your project, so the Bun global and all bun:* modules should be available immediately.
Contributing
The @types/bun package is a shim that loads bun-types. The bun-types package lives in the Bun repo under packages/bun-types.
To add a new file, add it under packages/bun-types. Then add a triple-slash directive pointing to it inside ./index.d.ts.
+ /// <reference path="./newfile.d.ts" />
bun build
