GoMoji 🔥

GoMoji makes it easy to detect, remove, replace, and look up emojis in Go strings.

It solves the common problem that emojis aren't always a single "character"—GoMoji handles them correctly so your string logic just works.

Table of Contents

• Installation
• Quick Start
• Features
• Usage Examples
  • Check for Emojis
  • Find All Emojis
  • Remove Emojis
  • Replace Emojis
  • Get Emoji Information
• API Documentation
• Automated Updates
• Performance
• Security
• Feedback
• Contributing
• License

Installation

Prerequisites

• Go 1.11 or higher (for module support)

Installing

go get -u github.com/forPelevin/gomoji

Quick Start

Create a minimal program that detects and removes emojis:

package main

import (
    "fmt"
    "github.com/forPelevin/gomoji"
)

func main() {
    s := "Hello 👋 world 🦋"
    fmt.Println(gomoji.ContainsEmoji(s)) // true
    fmt.Println(gomoji.RemoveEmojis(s))  // "Hello  world "
}

Then run:

go mod init example.com/hello
go get github.com/forPelevin/gomoji@latest
go run .

Features

• 🔎 Fast emoji detection in strings
• 👪 Find all emoji occurrences with detailed information
• 🌐 Access comprehensive emoji database
• 🧹 Remove emojis from strings
• ↔️ Replace emojis with custom characters
• ↕️ Custom emoji replacement functions
• 🧐 Detailed emoji information lookup
• 🔄 Automated Unicode updates via gomoji-updater

Usage Examples

Check for Emojis

package main

import "github.com/forPelevin/gomoji"

func main() {
    hasEmoji := gomoji.ContainsEmoji("hello world 🤗")
    println(hasEmoji) // true
}

Find All Emojis

emojis := gomoji.FindAll("🧖 hello 🦋 world")
// Returns slice of Emoji structs with detailed information

Remove Emojis

cleaned := gomoji.RemoveEmojis("🧖 hello 🦋 world")
println(cleaned) // "hello world"

Replace Emojis

// Replace with a specific character
replaced := gomoji.ReplaceEmojisWith("🧖 hello 🦋 world", '_')
println(replaced) // "_ hello _ world"

// Replace with custom function
customReplaced := gomoji.ReplaceEmojisWithFunc("🧖 hello 🦋 world", func(em Emoji) string {
    return em.Slug
})
println(customReplaced) // "person-in-steamy-room hello butterfly world"

Get Emoji Information

info, err := gomoji.GetInfo("🦋")
if err == nil {
    println(info.Slug)        // "butterfly"
    println(info.UnicodeName) // "E3.0 butterfly"
    println(info.Group)       // "Animals & Nature"
}

API Documentation

Emoji Structure

type Emoji struct {
    Slug        string `json:"slug"`        // Unique identifier
    Character   string `json:"character"`   // The emoji character
    UnicodeName string `json:"unicode_name"` // Official Unicode name
    CodePoint   string `json:"code_point"`  // Unicode code point
    Group       string `json:"group"`       // Emoji group category
    SubGroup    string `json:"sub_group"`   // Emoji subgroup category
}

Core Functions

• ContainsEmoji(s string) bool - Checks if a string contains any emoji
• FindAll(s string) []Emoji - Finds all unique emojis in a string
• CollectAll(s string) []Emoji - Finds all emojis including repeats (preserves order)
• RemoveEmojis(s string) string - Removes all emojis from a string
• ReplaceEmojisWith(s string, c rune) string - Replaces emojis with a specified character
• ReplaceEmojisWithSlug(s string) string - Replaces emojis with their slugs
• ReplaceEmojisWithFunc(s string, replacer func(Emoji) string) string - Replaces emojis via a custom function
• GetInfo(emoji string) (Emoji, error) - Gets detailed information about an emoji; returns ErrStrNotEmoji if not found
• AllEmojis() []Emoji - Returns all available emojis

For full reference documentation generated from source, see the package docs on pkg.go.dev: github.com/forPelevin/gomoji.

Automated Updates

GoMoji automatically stays up-to-date with the latest Unicode emoji standards through our automated update system:

• Daily Updates: Our GitHub Actions workflow runs daily to check for new Unicode emoji releases
• Automated PRs: When new emoji data is available, automated pull requests are created for review
• Source: Emoji data is fetched from the official Unicode Consortium: https://unicode.org/Public/emoji/latest/
• Tool: Updates are generated using gomoji-updater, a specialized tool for processing Unicode emoji data

Performance

GoMoji is designed for high performance, with parallel processing capabilities for optimal speed. Here are the key benchmarks:

Full benchmark details:

go test -bench=. -benchmem -v -run Benchmark ./...
goos: darwin
goarch: arm64
pkg: github.com/forPelevin/gomoji
cpu: Apple M1 Pro
BenchmarkContainsEmojiParallel-10               164229604                7.167 ns/op           0 B/op             0 allocs/op
BenchmarkContainsEmoji-10                       20967183                57.49 ns/op            0 B/op             0 allocs/op
BenchmarkReplaceEmojisWithSlugParallel-10        2160638               602.4 ns/op           160 B/op             3 allocs/op
BenchmarkReplaceEmojisWithSlug-10                 309879              3822 ns/op             160 B/op             3 allocs/op
BenchmarkRemoveEmojisParallel-10                 5794255               201.4 ns/op            68 B/op             2 allocs/op
BenchmarkRemoveEmojis-10                          830334              1454 ns/op              68 B/op             2 allocs/op
BenchmarkGetInfoParallel-10                     989043939                1.139 ns/op           0 B/op             0 allocs/op
BenchmarkGetInfo-10                             139558108                8.591 ns/op           0 B/op             0 allocs/op
BenchmarkFindAllParallel-10                      4029028               313.8 ns/op           288 B/op             2 allocs/op
BenchmarkFindAll-10                               751990              1494 ns/op             288 B/op             2 allocs/op

Note: Benchmarks were performed on Apple M1 Pro processor. Your results may vary depending on hardware.

Security

• This is a string-processing library, not a general-purpose sanitizer. Do not rely on it to prevent XSS or other injection attacks; use a proper HTML/markup sanitizer where needed.
• Emoji detection and replacement operate on Unicode grapheme clusters. Do not assume 1 code point == 1 visible symbol.
• Variation selectors are stripped during processing to normalize output. If your application depends on preserving exact variation selectors, avoid RemoveEmojis/Replace* or handle this explicitly.
• When replacing with slugs, treat the resulting text as untrusted like any other user-controlled string and escape/encode as appropriate for the output context.
• If you need normalization against visually confusable characters, use additional tooling (e.g., golang.org/x/text packages) alongside this library.

Feedback

• Bug report: please open an issue with a minimal repro and environment details.
• Feature request: suggest an enhancement describing the use case and expected behavior.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Requirements

• Follow Go’s style guidelines:
  • Effective Go
  • Go Code Review Comments
• Keep code formatted and linted: run make lint-fix (uses goimports, gofmt, and golangci-lint).
• Add tests for new functionality and fixes; all tests must pass: make test or go test ./....
• For performance-sensitive changes, include relevant benchmarks or comparisons (make bench).

How to contribute

1. Fork the repo and create a feature branch.
2. Make your changes, run linters and tests locally.
3. Open a PR describing the change and linking any related issue: open a pull request.

Contact

Vlad Gukasov

License

GoMoji is available under the MIT License. GoMoji source code is available under the MIT License.