Files
bun.sh/docs
Jarred Sumner bb4d5b9af5 feat(cli/run): add --parallel and --sequential for running multiple scripts with workspace support (#26551)
## Summary

Adds `bun run --parallel` and `bun run --sequential` — new flags for
running multiple package.json scripts concurrently or sequentially with
Foreman-style prefixed output. Includes full `--filter`/`--workspaces`
integration for running scripts across workspace packages.

### Usage

```bash
# Run "build" and "test" concurrently from the current package.json
bun run --parallel build test

# Run "build" and "test" sequentially with prefixed output
bun run --sequential build test

# Glob-matched script names
bun run --parallel "build:*"

# Run "build" in all workspace packages concurrently
bun run --parallel --filter '*' build

# Run "build" in all workspace packages sequentially
bun run --sequential --workspaces build

# Glob-matched scripts across all packages
bun run --parallel --filter '*' "build:*"

# Multiple scripts across all packages
bun run --parallel --filter '*' build lint test

# Continue running even if one package fails
bun run --parallel --no-exit-on-error --filter '*' test

# Skip packages missing the script
bun run --parallel --workspaces --if-present build
```

## How it works

### Output format

Each script's stdout/stderr is prefixed with a colored, padded label:

```
build | compiling...
test  | running suite...
lint  | checking files...
```

### Label format

- **Without `--filter`/`--workspaces`**: labels are just the script name
→ `build | output`
- **With `--filter`/`--workspaces`**: labels are `package:script` →
`pkg-a:build | output`
- **Fallback**: if a package.json has no `name` field, the relative path
from the workspace root is used (e.g., `packages/my-pkg:build`)

### Execution model

- **`--parallel`**: all scripts start immediately, output is interleaved
with prefixes
- **`--sequential`**: scripts run one at a time in order, each waiting
for the previous to finish
- **Pre/post scripts** (`prebuild`/`postbuild`) are grouped with their
main script and run in dependency order within each group
- By default, a failure kills all remaining scripts.
`--no-exit-on-error` lets all scripts finish.

### Workspace integration

The workspace branch in `multi_run.zig` uses a two-pass approach for
deterministic ordering:

1. **Collect**: iterate workspace packages using
`FilterArg.PackageFilterIterator` (same infrastructure as
`filter_run.zig`), filtering with `FilterArg.FilterSet`, collecting
matched packages with their scripts, PATH, and cwd.
2. **Sort**: sort matched packages by name (tiebreak by directory path)
for deterministic ordering — filesystem iteration order from the glob
walker is nondeterministic.
3. **Build configs**: for each sorted package, expand script names
(including globs like `build:*`) against that package's scripts map,
creating `ScriptConfig` entries with `pkg:script` labels and per-package
cwd/PATH.

### Behavioral consistency with `filter_run.zig`

| Behavior | `filter_run.zig` | `multi_run.zig` (this PR) |
|----------|-------------------|---------------------------|
| `--workspaces` skips root package | Yes | Yes |
| `--workspaces` errors on missing script | Yes | Yes |
| `--if-present` silently skips missing | Yes | Yes |
| `--filter` without `--workspaces` includes root | Yes (if matches) |
Yes (if matches) |
| Pre/post script chains | Per-package | Per-package |
| Per-package cwd | Yes | Yes |
| Per-package PATH (`node_modules/.bin`) | Yes | Yes |

### Key implementation details

- Each workspace package script runs in its own package directory with
its own `node_modules/.bin` PATH
- `dirpath` from the glob walker is duped to avoid use-after-free when
the iterator's arena is freed between patterns
- `addScriptConfigs` takes an optional `label_prefix` parameter — `null`
for single-package mode, package name for workspace mode
- `MultiRunProcessHandle` is registered in the `ProcessExitHandler`
tagged pointer union in `process.zig`

## Files changed

| File | Change |
|------|--------|
| `src/cli/multi_run.zig` | New file: process management, output
routing, workspace integration, dependency ordering |
| `src/cli.zig` | Dispatch to `MultiRun.run()` for
`--parallel`/`--sequential`, new context fields |
| `src/cli/Arguments.zig` | Parse `--parallel`, `--sequential`,
`--no-exit-on-error` flags |
| `src/bun.js/api/bun/process.zig` | Register `MultiRunProcessHandle` in
`ProcessExitHandler` tagged pointer union |
| `test/cli/run/multi-run.test.ts` | 118 tests (102 core + 16 workspace
integration) |
| `docs/pm/filter.mdx` | Document `--parallel`/`--sequential` +
`--filter`/`--workspaces` combination |
| `docs/snippets/cli/run.mdx` | Add `--parallel`, `--sequential`,
`--no-exit-on-error` parameter docs |

## Test plan

All 118 tests pass with debug build (`bun bd test
test/cli/run/multi-run.test.ts`). The 16 new workspace tests all fail
with system bun (`USE_SYSTEM_BUN=1`), confirming they test new
functionality.

### Workspace integration tests (16 tests)

1. `--parallel --filter='*'` runs script in all packages
2. `--parallel --filter='pkg-a'` runs only in matching package
3. `--parallel --workspaces` matches all workspace packages
4. `--parallel --filter='*'` with glob expands per-package scripts
5. `--sequential --filter='*'` runs in sequence (deterministic order)
6. Workspace + failure aborts other scripts
7. Workspace + `--no-exit-on-error` lets all finish
8. `--workspaces` skips root package
9. Each workspace script runs in its own package directory (cwd
verification)
10. Multiple script names across workspaces (`build` + `test`)
11. Pre/post scripts work per workspace package
12. `--filter` skips packages without the script (no error)
13. `--workspaces` errors when a package is missing the script
14. `--workspaces --if-present` skips missing scripts silently
15. Labels are padded correctly across workspace packages
16. Package without `name` field uses relative path as label

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
2026-01-29 20:20:39 -08:00
..
2026-01-29 01:22:53 -08:00
2025-11-10 17:38:48 -08:00
2026-01-29 01:22:53 -08:00
2026-01-29 01:22:53 -08:00

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