replace-in-files-cli

Replace matching strings and regexes in files

Install

npm install --global replace-in-files-cli

Usage

$ replace-in-files --help

  Usage
    $ replace-in-files <files…>

  Options
    --regex           Regex pattern to find  (Can be set multiple times)
    --string          String to find  (Can be set multiple times)
    --replacement     Replacement string  (Required)
    --ignore-case     Search case-insensitively
    --no-glob         Disable globbing
    --dry-run         Show what would be replaced without making changes

  Examples
    $ replace-in-files --string='horse' --regex='unicorn|rainbow' --replacement='🦄' foo.md
    $ replace-in-files --regex='v\d+\.\d+\.\d+' --replacement=v$npm_package_version foo.css
    $ replace-in-files --string='blob' --replacement='blog' 'some/**/[gb]lob/*' '!some/glob/foo'
    $ replace-in-files --dry-run --string='old' --replacement='new' file.txt

  You can use the same replacement patterns as with `String#replace()`, like `$&`.

  When working with quotes in shell commands, escape them with backslashes:
    $ replace-in-files --string='\"use strict\";' --replacement='\"use strict\";\nrequire(\"module\");' file.js

Real-world use-case: Bumping version number in a file when publishing to npm

The regex should be JavaScript flavor.

API

You can also use this package programmatically:

import replaceInFiles from 'replace-in-files-cli';

// Find and replace
await replaceInFiles('*.js', {
    find: ['old', /version \d+/],
    replacement: 'new'
});

// Transform entire file content
await replaceInFiles('*.js', {
    transform: (content, filePath) => `/* Banner */\n${content}`
});

// Combine find/replace with transform (transform runs after find/replace)
await replaceInFiles('*.js', {
    find: ['old'],
    replacement: 'new', 
    transform: (content, filePath) => `/* ${filePath} */\n${content}`
});

The transform option provides full control over file content:

• Standalone: Use alone for prepend, append, or complex transformations
• Combined: Use with find/replacement - transform runs after find/replace operations
• Parameters: Receives (content, filePath) for context-aware transformations