babel-watch

library7.8.1jsnpmunverified

A fast file watcher and restarter for babel-node apps. Instead of restarting babel-node on each change (which is slow), it runs babel transpilation once in a master process and spawns a plain node child with the transpiled code. Current stable version is 7.8.1, with a maintenance release cadence. Key differentiators: autowatch (automatically watches files as they are required), faster restarts than nodemon+babel-node, and supports Babel 7.

devops

npm install babel-watch

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-WATCH

babel-watch

devopsjavascriptv7.8.1

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Installs babel-watch as a dev dependency and creates an npm script to run it with a source file.

{ "scripts": { "start": "babel-watch src/main.js" } } # Then run: npm start

babel-watch --version

Debug

Known issues

breakingbabel-watch v7 requires Node >= 8 and @babel/core ^7.0.0. It will not work with older Node versions or Babel 6.

fix

Update Node to >=8 and install @babel/core@^7.

affects: >=7.0.0

gotchaWhen using --ignore, node_modules are ignored by default. If you specify a custom --ignore, you must include node_modules explicitly if you still want to ignore it.

fix

Use --ignore 'node_modules' along with other patterns, e.g., --ignore 'node_modules,dist'.

affects: >=7.0.0

gotchaThe --inspect option's address must be specified as a separate argument when using = syntax may cause issues.

fix

Use --inspect 0.0.0.0:9229 instead of --inspect=0.0.0.0:9229.

affects: >=7.0.0

deprecatedThe -d and -B debug options are deprecated; use --inspect or --inspect-brk instead.

fix

Replace -d with --inspect and -B with --inspect-brk.

affects: >=7.0.0

gotchaAutowatch may ignore files in node_modules by default but may still watch them if they are required. Use -x to exclude additional directories.

fix

Pass -x node_modules to exclude node_modules from autowatch.

affects: >=7.0.0

Errors

Common errors & fixes

babel-watch: error: unknown option `--config-file'

Using --config-file with babel-watch versions older than 7.5.0 which do not support that option.

fix

Update babel-watch to v7.5.0 or later: npm install babel-watch@latest

Error: Cannot find module '@babel/core'

@babel/core is a peer dependency of babel-watch and must be installed separately.

fix

Install @babel/core: npm install --save-dev @babel/core

babel-watch: FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory

The process ran out of memory due to large files or circular requires causing infinite loops.

fix

Increase Node memory limit with --max_old_space_size, or exclude unnecessary directories with --ignore.

(node:12345) [DEP0005] DeprecationWarning: ...

Using deprecated debug options (-d or -B).

fix

Use --inspect or --inspect-brk instead.

Error: listen EADDRINUSE :::9229

Another process is already using the inspector port when using --inspect without a custom port.

fix

Specify a different port with --inspect 0.0.0.0:9230

Upgrade

Version history

7.8.1latest on npm

Audit

Dependencies

@babel/coreoptionalPeer dependency; babel-watch requires @babel/core to be installed separately in the project to perform transpilation.

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/kmagiera/babel-watch ↗

packagehttps://www.npmjs.com/package/babel-watch ↗