gulp-replace

What is gulp-replace?

The gulp-replace npm package is a plugin for Gulp, a streaming build system, that allows you to search and replace text in files. It is useful for tasks such as modifying configuration files, updating version numbers, or replacing placeholders in templates.

What are gulp-replace's main functionalities?

Basic String Replacement

This feature allows you to replace a specific string with another string in the files matched by the gulp.src() method. In this example, all occurrences of 'foo' in text files within the 'src' directory are replaced with 'bar' and the modified files are saved to the 'dist' directory.

const gulp = require('gulp');
const replace = require('gulp-replace');

gulp.task('replace-text', function() {
  return gulp.src('src/*.txt')
    .pipe(replace('foo', 'bar'))
    .pipe(gulp.dest('dist'));
});

Regular Expression Replacement

This feature allows you to use regular expressions for more complex search and replace operations. In this example, any string matching the pattern 'foo' followed by one or more digits is replaced with 'bar'.

const gulp = require('gulp');
const replace = require('gulp-replace');

gulp.task('replace-regex', function() {
  return gulp.src('src/*.txt')
    .pipe(replace(/foo\d+/g, 'bar'))
    .pipe(gulp.dest('dist'));
});

Replacement with a Function

This feature allows you to use a function to determine the replacement value. The function receives the matched string and can return a modified version of it. In this example, all occurrences of 'foo' are replaced with 'FOO'.

const gulp = require('gulp');
const replace = require('gulp-replace');

gulp.task('replace-function', function() {
  return gulp.src('src/*.txt')
    .pipe(replace('foo', function(match) {
      return match.toUpperCase();
    }))
    .pipe(gulp.dest('dist'));
});

Other packages similar to gulp-replace

gulp-string-replace

gulp-string-replace is another Gulp plugin that provides similar functionality for string replacement. It allows for both simple string replacements and replacements using regular expressions. Compared to gulp-replace, it offers a more straightforward API but lacks some of the advanced features like replacement with a function.

gulp-replace-task

gulp-replace-task is a Gulp plugin designed for replacing text in files using a configuration object. It supports both string and regular expression replacements and allows for more complex replacement tasks through the use of configuration files. It is more suitable for projects that require extensive and configurable replacement tasks compared to gulp-replace.

gulp-batch-replace

gulp-batch-replace is a Gulp plugin that allows for batch replacements in files. It supports multiple replacements in a single pass and can handle both string and regular expression replacements. This package is useful for projects that need to perform multiple replacements efficiently, whereas gulp-replace is more focused on individual replacement tasks.

README

gulp-replace

A string replace plugin for gulp

Read me for gulp 3

Usage

First, install gulp-replace as a development dependency:

npm install --save-dev gulp-replace
# or
yarn add --dev gulp-replace

Then, add it to your gulpfile.js:

Simple string replace

const replace = require('gulp-replace');
const { src, dest } = require('gulp');

function replaceTemplate() {
  return src(['file.txt'])
    .pipe(replace('bar', 'foo'))
    .pipe(dest('build/'));
};

// or replace multiple strings
function replaceTemplate() {
  return src(['file.txt'])
    .pipe(replace('bar', 'foo'))
    .pipe(replace('baz', 'fuz'))
    .pipe(dest('build/'));
};

exports.replaceTemplate = replaceTemplate;

Simple regex replace

const replace = require('gulp-replace');
const { src, dest } = require('gulp');

function replaceTemplate() {
  return src(['file.txt'])
      // See https://mdn.io/string.replace#Specifying_a_string_as_a_parameter
      .pipe(replace(/foo(.{3})/g, '$1foo'))
      .pipe(dest('build/'));
};

exports.replaceTemplate = replaceTemplate;

String replace with function callback

const replace = require('gulp-replace');
const { src, dest } = require('gulp');

function replaceTemplate() {
  return src(['file.txt'])
    .pipe(replace('foo', function handleReplace(match){ return match.reverse(); })
    .pipe(dest('build/'))
};

exports.replaceTemplate = replaceTemplate;

Regex replace with function callback

const replace = require('gulp-replace');
const { src, dest } = require('gulp');

function replaceTemplate() {
  return src(['file.txt'])
    .pipe(replace(/foo(.{3})/g, function handleReplace(match, p1, offset, string) {
      // Replace foobaz with barbaz and log a ton of information
      // See https://mdn.io/string.replace#Specifying_a_function_as_a_parameter
      console.log('Found ' + match + ' with param ' + p1 + ' at ' + offset + ' inside of ' + string);
      return 'bar' + p1;
    }))
    .pipe(dest('build/'));
};

exports.replaceTemplate = replaceTemplate;

Function callback with file object

const replace = require('gulp-replace');
const { src, dest } = require('gulp');

function replaceTemplate() {
  return src(['file.txt'])
    .pipe(replace('filename', function handleReplace() {
         // Replaces instances of "filename" with "file.txt"
         // this.file is also available for regex replace
         // See https://github.com/gulpjs/vinyl#instance-properties for details on available properties
         return this.file.relative;
       }))
    .pipe(dest('build/'));
};

exports.replaceTemplate = replaceTemplate;

API

gulp-replace can be called with a string or regex.

replace(string, replacement[, options])

CAUTION: replacement could NOT be arrow function, because arrow function could not bind this

string

Type: String

The string to search for.

replacement

Type: String or Function

The replacement string or function. If replacement is a function, it will be called once for each match and will be passed the string that is to be replaced.

The value of this.file will be equal to the vinyl instance for the file being processed.

replace(regex, replacement[, options])

regex

Type: RegExp

The regex pattern to search for. See the MDN documentation for RegExp for details.

replacement

Type: String or Function

The replacement string or function. See the MDN documentation for String.replace for details on special replacement string patterns and arguments to the replacement function.

The value of this.file will be equal to the vinyl instance for the file being processed.

gulp-replace options

An optional third argument, options, can be passed.

options

Type: Object

options.skipBinary

Type: boolean
Default: true

Skip binary files. This option is true by default. If you want to replace content in binary files, you must explicitly set it to false.