shallowequal

shallowequal is like lodash's isEqual (v3.10.1) but for shallow (strict) equal.

shallowequal(value, other, [customizer], [thisArg])

Performs a shallow equality comparison between two values (i.e. value and other) to determine if they are equivalent.

The equality check returns true if value and other are already strictly equal, OR when all the following are true:

• value and other are both objects with the same keys
• For each key, the value in value and other are strictly equal (===)

If customizer (expected to be a function) is provided it is invoked to compare values. If customizer returns undefined (i.e. void 0), then comparisons are handled by the shallowequal function instead.

The customizer is bound to thisArg and invoked with three arguments: (value, other, key).

NOTE: Docs are (shamelessly) adapted from lodash's v3.x docs

Install

pnpm add shallowequal
# or
npm install shallowequal
# or
yarn add shallowequal

Usage

import shallowequal from "shallowequal";

const object = { user: "fred" };
const other = { user: "fred" };

object == other;
// → false

shallowequal(object, other);
// → true

TypeScript

This package includes TypeScript type definitions:

import shallowequal, { Comparator } from "shallowequal";

const customCompare: Comparator = (a, b, key) => {
  // Custom comparison logic
  return undefined; // Fall back to default comparison
};

shallowequal({ a: 1 }, { a: 1 }, customCompare);
// → true

Credit

Code for shallowEqual originated from https://github.com/gaearon/react-pure-render/ and has since been refactored to have the exact same API as lodash.isEqualWith (as of v4.17.4).

Development

Prerequisites:

• Node.js (v18+)
• pnpm

Setup

pnpm install

Commands

Using Make:

make install    # Install dependencies
make build      # Build the project
make test       # Run tests
make test-watch # Run tests in watch mode
make lint       # Run linter
make typecheck  # Run type checking
make clean      # Clean build artifacts
make ci         # Run full CI pipeline

Or using pnpm directly:

pnpm install    # Install dependencies
pnpm build      # Build the project
pnpm test       # Run tests
pnpm test:watch # Run tests in watch mode
pnpm lint       # Run linter
pnpm typecheck  # Run type checking

License

MIT.